Patent Application
20210237765
This nonprovisional application is based on Japanese Patent Application No. 2020-015715 filed with the Japan Patent Office on Jan. 31, 2020, the entire contents of which are hereby incorporated by reference.
The present disclosure relates to a vehicle including an autonomous driving system, a vehicle control interface box, and an autonomous driving vehicle.
Japanese Patent Laying-Open No. 2018-132015 discloses a vehicle incorporating an autonomous driving system. The vehicle incorporates a motive power system, a power supply system, and the autonomous driving system. The motive power system manages motive power of the vehicle in a centralized manner. The power supply system manages charging and discharging power of a battery mounted on the vehicle or supply of electric power to various vehicle-mounted devices in a centralized manner. The autonomous driving system carries out autonomous driving control of the vehicle in a centralized manner. An engine ECU of the motive power system, a power supply ECU of the power supply system, and an autonomous driving ECU of the autonomous driving system are communicatively connected to one another over a vehicle-mounted network.
An autonomous driving system developed by an autonomous driving system developer may externally be attached to a vehicle main body. In this case, autonomous driving is carried out under vehicle control by a vehicle platform (which will be described later) in accordance with an instruction from the externally attached autonomous driving system.
In such a vehicle, an interface for various instructions and signals exchanged between the autonomous driving system and the vehicle platform is important. When the externally attached autonomous driving system carries out autonomous driving, how to control a power supply of the vehicle from the autonomous driving system is also important. Japanese Patent Laying-Open No. 2018-132015 does not particularly discuss such an aspect.
The present disclosure was made to solve such a problem, and an object of the present disclosure is to control a power supply mode of a vehicle platform from an autonomous driving system in a vehicle that carries out autonomous driving.
A vehicle according to the present disclosure is a vehicle on which an autonomous driving system (an ADS or an ADK) that creates a driving plan is mountable, and the vehicle includes a vehicle platform (VP) that carries out vehicle control in accordance with an instruction from the autonomous driving system and a vehicle control interface box (VCIB) that interfaces between the vehicle platform and the autonomous driving system. The vehicle control interface box receives a power supply mode request from the autonomous driving system, the power supply mode request being an instruction for controlling a power supply mode of the vehicle platform. The power supply mode includes a sleep mode (Sleep) in which the vehicle is in a Ready OFF state, a driving mode (Driving Mode) in which the vehicle is in a Ready ON state, and a wake mode (Wake) in which the vehicle control interface box is on.
In the vehicle, three power supply modes of the sleep mode, the driving mode, and the wake mode are provided. The vehicle control interface box receives from the autonomous driving system, a power supply mode request which is an instruction for controlling the power supply mode. Therefore, according to the vehicle, the power supply mode of the vehicle platform can be controlled from the autonomous driving system through the vehicle control interface box.
The vehicle platform may include a high-voltage battery and an auxiliary battery. The wake mode may be a mode in which the vehicle control interface box is on by power feed from the auxiliary battery without power feed from the high-voltage battery.
According to the vehicle, the wake mode in which the vehicle control interface box is on by power feed from the auxiliary battery without power feed from the high-voltage battery can be set from the autonomous driving system through the vehicle control interface box.
The vehicle control interface box may not receive a next power supply mode request for a certain time period after reception of the power supply mode request from the autonomous driving system. The certain time period is set, for example, to substantially 4000 milliseconds.
According to such a configuration, the power supply mode can be prevented from being unduly switched in a short period of time.
The vehicle control interface box may transmit a power supply mode status that indicates a status of the power supply mode of the vehicle platform to the autonomous driving system.
According to such a configuration, the autonomous driving system can recognize a status of the power supply mode of the vehicle platform and can carry out appropriate control in accordance with each mode.
The vehicle control interface box may transmit the sleep mode as the power supply mode status to the autonomous driving system for a prescribed time period after sleep processing is performed in accordance with a request for the sleep mode, and thereafter may shut down. The prescribed time period is set, for example, to substantially 3000 milliseconds.
Since the vehicle control interface box also shuts down during the sleep mode, the autonomous driving system cannot be notified of the power supply mode status by the vehicle control interface box. According to the configuration, however, the autonomous driving system can be notified of transition of the power supply mode to the sleep mode by the vehicle control interface box.
The foregoing and other objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of the present disclosure when taken in conjunction with the accompanying drawings.
An embodiment of the present disclosure will be described below in detail with reference to the drawings. The same or corresponding elements in the drawings have the same reference characters allotted and description thereof will not be repeated.
Referring to
Vehicle 10 includes a vehicle main body 100 and an autonomous driving kit (which is denoted as “ADK” below) 200. Vehicle main body 100 includes a vehicle control interface 110, a vehicle platform (which is denoted as “VP” below) 120, and a data communication module (DCM) 190.
Vehicle 10 can carry out autonomous driving in accordance with commands from ADK 200 attached to vehicle main body 100. Though
Vehicle control interface 110 can communicate with ADK 200 over a controller area network (CAN). Vehicle control interface 110 receives various commands from ADK 200 or outputs a state of vehicle main body 100 to ADK 200 by executing a prescribed application programming interface (API) defined for each communicated signal.
When vehicle control interface 110 receives a command from ADK 200, it outputs a control command corresponding to the received command to VP 120. Vehicle control interface 110 obtains various types of information on vehicle main body 100 from VP 120 and outputs the state of vehicle main body 100 to ADK 200. A configuration of vehicle control interface 110 will be described in detail later.
VP 120 includes various systems and various sensors for controlling vehicle main body 100. VP 120 carries out various types of vehicle control in accordance with a command given from ADK 200 through vehicle control interface 110. Namely, as VP 120 carries out various types of vehicle control in accordance with a command from ADK 200, autonomous driving of vehicle 10 is carried out. A configuration of VP 120 will also be described in detail later.
ADK 200 includes an autonomous driving system (which is denoted as “ADS” below) for autonomous driving of vehicle 10. ADK 200 creates a driving plan of vehicle 10 and outputs various commands for traveling vehicle 10 in accordance with the created driving plan to vehicle control interface 110 in accordance with the API defined for each command. ADK 200 receives various signals indicating states of vehicle main body 100 from vehicle control interface 110 in accordance with the API defined for each signal and has the received vehicle state reflected on creation of the driving plan. A configuration of ADK 200 (ADS) will also be described later.
DCM 190 includes a communication interface (I/F) for vehicle main body 100 to wirelessly communicate with data server 500. DCM 190 outputs various types of vehicle information such as a speed, a position, or an autonomous driving state to data server 500. DCM 190 receives from autonomous driving related mobility services 700 through MSPF 600 and data server 500, various types of data for management of travel of an autonomous driving vehicle including vehicle 10 by mobility services 700.
MSPF 600 is an integrated platform to which various mobility services are connected. In addition to autonomous driving related mobility services 700, not-shown various mobility services (for example, various mobility services provided by a ride-share company, a car-sharing company, an insurance company, a rent-a-car company, and a taxi company) are connected to MSPF 600. Various mobility services including mobility services 700 can use various functions provided by MSPF 600 by using APIs published on MSPF 600, depending on service contents.
Autonomous driving related mobility services 700 provide mobility services using an autonomous driving vehicle including vehicle 10. Mobility services 700 can obtain, for example, operation control data of vehicle 10 that communicates with data server 500 or information stored in data server 500 from MSPF 600, by using the APIs published on MSPF 600. Mobility services 700 transmit, for example, data for managing an autonomous driving vehicle including vehicle 10 to MSPF 600, by using the API.
MSPF 600 publishes APIs for using various types of data on vehicle states and vehicle control necessary for development of the ADS, and an ADS provider can use as the APIs, the data on the vehicle states and vehicle control necessary for development of the ADS stored in data server 500.
During autonomous driving of vehicle 10, compute assembly 210 obtains an environment around the vehicle and a pose, a behavior, and a position of vehicle 10 from various sensors which will be described later. Compute assembly 210 obtains a state of vehicle 10 from VP 120 through vehicle control interface 110 and sets a next operation (acceleration, deceleration, or turning) of vehicle 10. Then, compute assembly 210 outputs various commands for realizing a set operation of vehicle 10 to vehicle control interface 110.
HMI system 230 presents information to a user and accepts an operation during autonomous driving, during driving requiring an operation by a user, or at the time of transition between autonomous driving and driving requiring an operation by the user. HMI system 230 includes, for example, a touch panel display, a display apparatus, and an operation apparatus.
Sensors for perception 260 include sensors that perceive an environment around the vehicle, and include, for example, at least any of laser imaging detection and ranging (LIDAR), a millimeter-wave radar, and a camera.
The LIDAR refers to a distance measurement apparatus that measures a distance based on a time period from emission of pulsed laser beams (for example, infrared rays) until return of the laser beams reflected by an object. The millimeter-wave radar is a distance measurement apparatus that measures a distance or a direction to an object by emitting radio waves short in wavelength to the object and detecting radio waves that return from the object. The camera is arranged, for example, on a rear side of a room mirror in a compartment and used for shooting the front of vehicle 10. As a result of image processing by artificial intelligence (AI) or an image processing processor onto images or video images shot by the camera, another vehicle, an obstacle, or a human in front of vehicle 10 can be recognized. Information obtained by sensors for perception 260 is output to compute assembly 210.
Sensors for pose 270 include sensors that detect a pose, a behavior, or a position of vehicle 10, and include, for example, an inertial measurement unit (IMU) or a global positioning system (GPS).
The IMU detects, for example, an acceleration in a front-rear direction, a lateral direction, and a vertical direction of vehicle 10 and an angular speed in a roll direction, a pitch direction, and a yaw direction of vehicle 10. The GPS detects a position of vehicle 10 based on information received from a plurality of GPS satellites that orbit the Earth. Information obtained by sensors for pose 270 is output to compute assembly 210.
Sensor cleaning 290 removes soiling attached to various sensors. Sensor cleaning 290 removes soiling attached to a lens of the camera or a portion from which laser beams or radio waves are emitted, for example, with a cleaning solution or a wiper.
Vehicle control interface 110 includes vehicle control interface boxes (each of which is denoted as a “VCIB” below) 111A and 111B. Each of VCIBs 111A and 111B includes an ECU, and specifically contains a central processing unit (CPU) and a memory (a read only memory (ROM) and a random access memory (RAM)) (neither of which is shown). Though VCIB 111B is equivalent in function to VCIB 111A, it is partially different in a plurality of systems connected thereto that make up VP 120.
Each of VCIBs 111A and 111B is communicatively connected to compute assembly 210 of ADK 200 over the CAN or the like. VCIB 111A and VCIB 111B are communicatively connected to each other.
VCIBs 111A and 111B relay various commands from ADK 200 and output them as control commands to VP 120. Specifically, VCIBs 111A and 111B convert various commands obtained from ADK 200 in accordance with the API into control commands to be used for control of each system of VP 120 by using information such as a program stored in a memory and output the control commands to a destination system. VCIBs 111A and 111B relay vehicle information output from VP 120 and output the vehicle information as a vehicle state to ADK 200 in accordance with prescribed APIs.
As VCIBs 111A and 111B equivalent in function relating to an operation of at least one of (for example, braking or steering) systems are provided, control systems between ADK 200 and VP 120 are redundant. Thus, when some kind of failure occurs in a part of the system, the function (turning or stopping) of VP 120 can be maintained by switching between the control systems as appropriate or disconnecting a control system where failure has occurred.
VP 120 includes brake systems 121A and 121B, steering systems 122A and 122B, an electric parking brake (EPB) system 123A, a P-Lock system 123B, a propulsion system 124, a pre-crash safety (PCS) system 125, and a body system 126.
VCIB 111A is communicatively connected to brake system 121B, steering system 122A, EPB system 123A, P-Lock system 123B, propulsion system 124, and body system 126 of the plurality of systems included in VP 120, through a communication bus.
VCIB 111B is communicatively connected to brake system 121A, steering system 122B, and P-Lock system 123B of the plurality of systems included in VP 120, through a communication bus.
Brake systems 121A and 121B can control a plurality of braking apparatuses provided in wheels of vehicle 10. Brake system 121B may be equivalent in function to brake system 121A, or one of brake systems 121A and 121B may be able to independently control braking force of each wheel during travel of the vehicle and the other thereof may be able to control braking force such that equal braking force is generated in the wheels during travel of the vehicle. The braking apparatus includes, for example, a disc brake system that is operated with a hydraulic pressure regulated by an actuator.
A wheel speed sensor 127 is connected to brake system 121B. Wheel speed sensor 127 is provided in each wheel of vehicle 10 and detects a rotation speed of each wheel. Wheel speed sensor 127 outputs the detected rotation speed of each wheel to brake system 121B. Brake system 121B outputs the rotation speed of each wheel to VCIB 111A as one of pieces of information included in vehicle information.
Brake systems 121A and 121B each generate a braking instruction to a braking apparatus in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110. For example, brake systems 121A and 121B control the braking apparatus based on a braking instruction generated in one of brake systems 121A and 121B, and when a failure occurs in one of the brake systems, the braking apparatus is controlled based on a braking instruction generated in the other brake system.
Steering systems 122A and 122B can control a steering angle of a steering wheel of vehicle 10 with a steering apparatus. Steering system 122B is similar in function to steering system 122A. The steering apparatus includes, for example, rack-and-pinion electric power steering (EPS) that allows adjustment of a steering angle by an actuator.
A pinion angle sensor 128A is connected to steering system 122A. A pinion angle sensor 128B provided separately from pinion angle sensor 128A is connected to steering system 122B. Each of pinion angle sensors 128A and 128B detects an angle of rotation (a pinion angle) of a pinion gear coupled to a rotation shaft of the actuator. Pinion angle sensors 128A and 128B output detected pinion angles to steering systems 122A and 122B, respectively.
Steering systems 122A and 122B each generate a steering instruction to the steering apparatus in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110. For example, steering systems 122A and 122B control the steering apparatus based on the steering instruction generated in one of steering systems 122A and 122B, and when a failure occurs in one of the steering systems, the steering apparatus is controlled based on a steering instruction generated in the other steering system.
EPB system 123A can control the EPB provided in at least any of wheels of vehicle 10. The EPB is provided separately from the braking apparatus, and fixes a wheel by an operation of an actuator. The EPB, for example, activates a drum brake for a parking brake provided in at least one of wheels of vehicle 10 to fix the wheel, or activates a braking apparatus to fix a wheel with an actuator capable of regulating a hydraulic pressure to be supplied to the braking apparatus separately from brake systems 121A and 121B.
EPB system 123A controls the EPB in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110.
P-Lock system 123B can control a P-Lock apparatus provided in a transmission of vehicle 10. The P-Lock apparatus fixes rotation of an output shaft of the transmission by fitting a protrusion provided at a tip end of a parking lock pawl, a position of which is adjusted by an actuator, into a tooth of a gear (locking gear) provided as being coupled to a rotational element in the transmission.
P-Lock system 123B controls the P-Lock apparatus in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110.
Propulsion system 124 can switch a shift range with the use of a shift apparatus and can control driving force of vehicle 10 in a direction of travel that is generated from a drive source. The shift apparatus can select any of a plurality of shift ranges. The drive source includes, for example, a motor generator and an engine.
Propulsion system 124 controls the shift apparatus and the drive source in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110.
PCS system 125 controls vehicle 10 to avoid collision or to mitigate damage by using a camera/radar 129. PCS system 125 is communicatively connected to brake system 121B. PCS system 125 detects an obstacle (an obstacle or a human) in front by using, for example, camera/radar 129, and when it determines that there is possibility of collision based on a distance to the obstacle, it outputs a braking instruction to brake system 121B so as to increase braking force.
Body system 126 can control, for example, components such as a direction indicator, a horn, or a wiper, depending on a state or an environment of travel of vehicle 10. Body system 126 controls each component in accordance with a prescribed control command received from ADK 200 through vehicle control interface 110.
An operation apparatus that can manually be operated by a user for the braking apparatus, the steering apparatus, the EPB, P-Lock, the shift apparatus, and the drive source described above may separately be provided.
Referring to
High-voltage battery 150 includes a plurality of (for example, several hundred) cells. Each cell is, for example, a secondary battery such as a lithium ion battery or a nickel metal hydride battery. High-voltage battery 150 outputs electric power for generating driving force of vehicle 10 to a vehicle drive system (not shown). A voltage of high-voltage battery 150 is, for example, several hundred volts. Instead of high-voltage battery 150, a power storage element such as an electric double layer capacitor may be employed.
DC/DC converter 152 is electrically connected between high-voltage battery 150 and a power line PL1. DC/DC converter 152 down-converts electric power supplied from high-voltage battery 150 to an auxiliary machinery voltage (for example, more than ten volts or several ten volts) lower than the voltage of high-voltage battery 150 and outputs down-converted electric power to power line PL1, in accordance with an instruction from a not-shown ECU. DC/DC converter 152 is implemented, for example, by an isolated DC/DC converter including a transformer.
Auxiliary battery 154 is electrically connected to power line PL1. Auxiliary battery 154 is a chargeable and dischargeable secondary battery, and implemented, for example, by a lead acid battery. Auxiliary battery 154 can store electric power output from DC/DC converter 152 to power line PL1. Auxiliary battery 154 can feed stored electric power to each system electrically connected to power line PL1.
Switching DC/DC converter 156 is electrically connected between power line PL1 and a power line PL2. Switching DC/DC converter 156 supplies electric power from power line PL1 to power line PL2 in accordance with an instruction from the ECU. When switching DC/DC converter 156 receives a shutdown instruction from the ECU, it electrically disconnects power line PL2 (secondary battery 158) from power line PL1 by shutting down. Switching DC/DC converter 156 is implemented, for example, by a chopper DC/DC converter that can switch between conduction and disconnection by a semiconductor switching element.
Secondary battery 158 is electrically connected to power line PL2. Secondary battery 158 is a chargeable and dischargeable secondary battery, and implemented, for example, by a lithium ion secondary battery. Secondary battery 158 can store electric power output from switching DC/DC converter 156 to power line PL2. Secondary battery 158 can supply stored electric power to each system electrically connected to power line PL2.
DC/DC converter 152 and auxiliary battery 154 implement a primary power supply system of VP 120. Brake system 121A, steering system 122A, EPB system 123A, propulsion system 124, PCS system 125, body system 126, and VCIB 111A are electrically connected to power line PL1 which is a power supply line of the primary power supply system, and these systems receive supply of electric power from the primary power supply system.
Switching DC/DC converter 156 and secondary battery 158 implement a secondary power supply system of VP 120. Brake system 121B, steering system 122B, P-Lock system 123B, and VCIB 111B are electrically connected to power line PL2 which is a power supply line of the secondary power supply system, and these systems receive supply of electric power from the secondary power supply system.
The secondary power supply system constituted of switching DC/DC converter 156 and secondary battery 158 functions as a redundant power supply for the primary power supply system constituted of DC/DC converter 152 and auxiliary battery 154. When a power feed function of the primary power supply system fails and power cannot be fed to each system connected to power line PL1, the secondary power supply system continues power feed to each system connected to power line PL2 at least for a certain period of time such that the function of VP 120 is not immediately completely lost.
More specifically, for example, when failure of the power feed function of the primary power supply system is detected due to abnormal lowering in voltage of power line PL1, switching DC/DC converter 156 shuts down to electrically disconnect secondary battery 158 from the primary power supply system, and power feed from secondary battery 158 to each system connected to power line PL2 is continued. A capacity of secondary battery 158 is designed such that power can be fed from secondary battery 158 at least for a certain period of time after shutdown of switching DC/DC converter 156.
If it is assumed that power feed from the secondary power supply system (secondary battery 158) to all systems is continued in case of failure of the power feed function of the primary power supply system, secondary battery 158 of a large capacity should be prepared or a time period for which power feed from secondary battery 158 is continued should be made shorter. In the embodiment, a system that receives supply of electric power from the secondary power supply system (secondary battery 158) is limited to brake system 121B, steering system 122B, P-Lock system 123B, and VCIB 111B. Therefore, the capacity of secondary battery 158 can be suppressed and power feed to the limited systems can be continued at least for a certain period of time.
Though not particularly shown, power may be fed from high-voltage battery 150 of VP 120 also to ADK 200 (ADS) and the primary power supply system and the secondary power supply system as the redundant power supply may be configured within ADK 200 as in VP 120.
<Description of Power Supply Mode>
Vehicle 10 according to the present embodiment includes three power supply modes of a sleep mode (Sleep), a wake mode (Wake), and a driving mode (Driving Mode) as power supply modes that indicate a power supply state of vehicle 10.
The wake mode (Wake) refers to a state that VCIB 111 is on by power feed from auxiliary battery 154. In the wake mode, power is not fed from high-voltage battery 150, and ECUs other than VCIB 111 are not on except for some body-related ECUs (for example, a verification ECU for verifying a smart key or a body ECU that controls locking/unlocking of a door) in body system 126.
In the wake mode, VCIB 111 performs processing such as establishment of communication with ADK 200, device authentication to authenticate whether or not ADK 200 is a registered device, turn-on of the above-described some body-related ECUs, or execution of the APIs associated with these ECUs.
In the sleep mode, when VCIB 111 receives a power supply mode request command that indicates transition to the wake mode from ADK 200 in accordance with a prescribed API, the power supply mode makes transition from the sleep mode to the wake mode.
The driving mode (Driving Mode) refers to a state in which power of the vehicle is on, that is, “Ready ON” state. In the driving mode, power is fed from high-voltage battery 150 to each system and VCIB 111 and each system of VP 120 are on.
In the wake mode, when VCIB 111 receives a power supply mode request command that indicates transition to the driving mode from ADK 200 in accordance with the prescribed API, the power supply mode makes transition from the wake mode to the driving mode.
In the driving mode, when VCIB 111 receives a power supply mode request command that indicates transition to the sleep mode from ADK 200 in accordance with the prescribed API, the power supply mode makes transition from the driving mode to the sleep mode.
In the sleep mode, when a start switch of the vehicle is switched on while a driver holds a key, the power supply mode makes transition from the sleep mode to the driving mode.
The power supply mode request command can take any of values 00 to 06 as an argument. The value 00 is set when no request for the power supply mode of VP 120 is issued from ADK 200 (No request). When VCIB 111 receives the power supply mode request command in which the value 00 has been set, VP 120 maintains the power supply mode at that time.
A value 01 is set when a request for the sleep mode (Sleep) is issued from ADK 200. When VCIB 111 receives the power supply mode request command in which the value 01 has been set, the power supply mode makes transition to the sleep mode and VP 120 is set to the Ready OFF state.
A value 02 is set when a request for the wake mode (Wake) is issued from ADK 200. When VCIB 111 receives the power supply mode request command in which the value 02 has been set, the power supply mode makes transition to the wake mode and VCIB 111 is turned on by receiving power feed from the auxiliary battery. The value 06 is set when a request for the driving mode (Driving Mode) is issued from ADK 200. When VCIB 111 receives the power supply mode request command in which the value 06 has been set, the power supply mode makes transition to the driving mode and VP 120 is set to the Ready ON state. Values 03 to 05 are reserved.
The API for input of the power supply mode request command from ADK 200 is configured not to accept a next power supply mode request command for a certain time period (4000 ms) after it receives a certain power supply mode request command. Specifically, VCIB 111 does not receive a next power supply mode request command for the certain time period after it receives a power supply mode request command from ADK 200. The power supply mode can thus be prevented from being unduly switched in a short period of time in VP 120.
A power supply mode status signal transmitted to ADK 200 can take any of values 00 to 07 as an argument. The values 01, 02, and 06 are set when the power supply mode is set to the sleep mode (Sleep), the wake mode (Wake), and the driving mode (Driving Mode), respectively. The value 07 is set when some unhealthy situation occurs in the power supply of VP 120. The values 00 and 03 to 05 are reserved.
When switching to the sleep mode is requested (in a power supply mode request command from ADK 200 or by an operation to switch off the start switch by a driver), VCIB 111 outputs a power supply mode status signal to ADK 200 with the value 01 (sleep mode) being set therein for a prescribed time period (3000 ms) after sleep processing to set VP 120 to the Ready OFF state, and thereafter shuts down. Since VCIB 111 also shuts down during the sleep mode, VCIB 111 is unable to notify ADK 200 of the power supply mode status. According to the configuration above, however, VCIB 111 can notify ADK 200 of transition of the power supply mode to the sleep mode.
Referring to
Then, VCIB 111 establishes communication with ADK 200, and after communication is established, it performs device authentication processing for ADK 200 (step S25). VCIB 111 outputs a turn-on instruction to some body-related ECUs (the verification ECU or the body ECU) and turns on APIs associated with these ECUs (step S30).
As device authentication of ADK 200 is completed (YES in step S35), VCIB 111 determines whether or not a certain time period (4000 ms) has elapsed since reception of the power supply mode request from ADK 200 (that is, turn-on of VCIB 111) (step S40).
When VCIB 111 determines that the certain time period has elapsed since reception of the power supply mode request (YES in step S40), VCIB 111 determines whether or not it has received the power supply mode request command in which the value 06 (Driving Mode) has been set from ADK 200 (step S45).
When VCIB 111 receives the power supply mode request command in which the value 06 has been set (YES in step S45), VCIB 111 instructs VP 120 to enter the Ready ON state (step S50). In VP 120, DC/DC converter 152 (
When VP 120 enters the Ready ON state (YES in step S55), VCIB 111 sets the value 06 (Driving Mode) in the power supply mode status signal and outputs the power supply mode status signal to ADK 200 (step S60).
Referring to
When VP 120 enters the Ready OFF state and sleep processing is completed (YES in step S120), VCIB 111 sets the value 01 (sleep mode) in the power supply mode status signal and outputs the power supply mode status signal to ADK 200 (step S125).
Then, VCIB 111 determines whether or not a prescribed time period (3000 ms) has elapsed since output to ADK 200, of the power supply mode status signal in which the value 01 has been set (step S130). During this period, VCIB 111 prepares for shut-down of the VCIB itself.
When the prescribed time period has elapsed (YES in step S130), VCIB 111 stops communication with ADK 200 and shuts down (step S135).
As set forth above, in this embodiment, there are three power supply modes of the sleep mode (Sleep), the driving mode (Driving Mode), and the wake mode (Wake), and VCIB 111 receives a power supply mode request which is an instruction for control of the power supply mode from ADK 200. Therefore, according to this embodiment, ADK 200 can control the power supply mode of VP 120 through VCIB 111.
In this embodiment, VCIB 111 does not receive a next power supply mode request for a certain time period (4000 ms) after reception of a power supply mode request from ADK 200. The power supply mode can thus be prevented from unduly switching in a short period of time.
In this embodiment, VCIB 111 transmits to ADK 200, the power supply mode status signal that indicates a status of the power supply mode of VP 120. ADK 200 can thus recognize the status of the power supply mode of VP 120 and can carry out appropriate control in accordance with each mode.
In this embodiment, VCIB 111 transmits a power supply mode status signal in which the value 01 (sleep mode) has been set to ADK 200 for a prescribed time period (3000 ms) after sleep processing in accordance with a request for the sleep mode, and thereafter shuts down. VCIB 111 can thus notify ADK 200 of transition of the power supply mode to the sleep mode.
Toyota's MaaS Vehicle Platform
API Specification
for ADS Developers
[Standard Edition #0.1]
History of Revision
Index
This document is an API specification of Toyota Vehicle Platform and contains the outline, the usage and the caveats of the application interface.
e-Palette, MaaS vehicle based on the POV (Privately Owned Vehicle) manufactured by Toyota
This is an early draft of the document.
All the contents are subject to change. Such changes are notified to the users.
Please note that some parts are still T.B.D. will be updated in the future.
The overall structure of MaaS with the target vehicle is shown (
Vehicle control technology is being used as an interface for technology providers.
Technology providers can receive open API such as vehicle state and vehicle control, necessary for development of automated driving systems.
The system architecture as a premise is shown (
The target vehicle will adopt the physical architecture of using CAN for the bus between ADS and VCIB. In order to realize each API in this document, the CAN frames and the bit assignments are shown in the form of “bit assignment table” as a separate document.
Basic responsibility sharing between ADS and vehicle VP is as follows when using APIs.
[ADS]
The ADS should create the driving plan, and should indicate vehicle control values to the VP.
[VP]
The Toyota VP should control each system of the VP based on indications from an ADS.
In this section, typical usage of APIs is described.
CAN will be adopted as a communication line between ADS and VP. Therefore, basically, APIs should be executed every defined cycle time of each API by ADS.
A typical workflow of ADS of when executing APIs is as follows (
In this section, the APIs for vehicle motion control which is controllable in the MaaS vehicle is described.
3.3.1. Functions
3.3.1.1. Standstill, Start Sequence
The transition to the standstill (immobility) mode and the vehicle start sequence are described. This function presupposes the vehicle is in Autonomy_State=Autonomous Mode. The request is rejected in other modes.
The below diagram shows an example.
Acceleration Command requests deceleration and stops the vehicle. Then, when Longitudinal_Velocity is confirmed as 0 [km/h], Standstill Command=“Applied” is sent. After the brake hold control is finished, Standstill Status becomes “Applied”. Until then, Acceleration Command has to continue deceleration request. Either Standstill Command=“Applied” or Acceleration Command's deceleration request were canceled, the transition to the brake hold control will not happen. After that, the vehicle continues to be standstill as far as Standstill Command=“Applied” is being sent. Acceleration Command can be set to 0 (zero) during this period.
If the vehicle needs to start, the brake hold control is cancelled by setting Standstill Command to “Released”. At the same time, acceleration/deceleration is controlled based on Acceleration Command (
EPB is engaged when Standstill Status=“Applied” continues for 3 minutes.
3.3.1.2. Direction Request Sequence
The shift change sequence is described. This function presupposes that Autonomy_State=Autonomous Mode. Otherwise, the request is rejected.
Shift change happens only during Actual_Moving_Direction=“standstill”). Otherwise, the request is rejected.
In the following diagram shows an example. Acceleration Command requests deceleration and makes the vehicle stop. After Actual_Moving_Direction is set to “standstill”, any shift position can be requested by Propulsion Direction Command. (In the example below, “D”→“R”).
During shift change, Acceleration Command has to request deceleration.
After the shift change, acceleration/deceleration is controlled based on Acceleration Command value (
3.3.1.3. WheelLock Sequence
The engagement and release of wheel lock is described. This function presupposes Autonomy_State=Autonomous Mode, otherwise the request is rejected.
This function is conductible only during vehicle is stopped. Acceleration Command requests deceleration and makes the vehicle stop. After Actual_Moving_Direction is set to “standstill”, WheelLock is engaged by Immobilization Command=“Applied”. Acceleration Command is set to Deceleration until Immobilization Status is set to “Applied”.
If release is desired, Immobilization Command=“Release” is requested when the vehicle is stationary. Acceleration Command is set to Deceleration at that time.
After this, the vehicle is accelerated/decelerated based on Acceleration Command value (
3.3.1.4. Road_Wheel_Angle Request
This function presupposes Autonomy_State=“Autonomous Mode”, and the request is rejected otherwise.
Tire Turning Angle Command is the relative value from Estimated_Road_Wheel_Angle_Actual.
For example, in case that Estimated_Road_Wheel_Angle_Actual=0.1 [rad] while the vehicle is going straight;
If ADS requests to go straight ahead, Tire Turning Angle Command should be set to 0+0.1=0.1 [rad].
If ADS requests to steer by −0.3 [rad], Tire Turning Angle Command should be set to −0.3+0.1=−0.2 [rad].
3.3.1.5. Rider Operation
3.3.1.5.1. Acceleration Pedal Operation
While in Autonomous driving mode, accelerator pedal stroke is eliminated from the vehicle acceleration demand selection.
3.3.1.5.2. Brake Pedal Operation
The action when the brake pedal is operated. In the autonomy mode, target vehicle deceleration is the sum of 1) estimated deceleration from the brake pedal stroke and 2) deceleration request from AD system.
3.3.1.5.3. Shift_Lever_Operation
In Autonomous driving mode, driver operation of the shift lever is not reflected in Propulsion Direction Status.
If necessary, ADS confirms Propulsion Direction by Driver and changes shift position by using Propulsion Direction Command.
3.3.1.5.4. Steering Operation
When the driver (rider) operates the steering, the maximum is selected from
Note that Tire Turning Angle Command is not accepted if the driver strongly turns the steering wheel. The above-mentioned is determined by Steering_Wheel_Intervention flag.
3.3.2. Inputs
3.3.2.1. Propulsion Direction Command
Request to switch between forward (D range) and back (R range)
Values
Remarks
3.3.2.2. Immobilization Command
Request to engage/release WheelLock
Values
Remarks
3.3.2.3. Standstill Command
Request the vehicle to be stationary
Values
Remarks
“Applied” and Acceleration Command's deceleration request (−0.4 m/s′) should be continued.
3.3.2.4. Acceleration Command
Command vehicle acceleration
Values
Estimated_Max_Decel_Capability to Estimated_Max_Accel_Capability [m/s2]
Remarks
3.3.2.5. Tire Turning Angle Command
Command Tire Turning Angle
Values
Remarks
3.3.2.6. Autonomization Command
Request to transition between manual mode and autonomy mode
Values
3.3.3. Outputs
3.3.3.1. Propulsion Direction Status
Current shift range
Values
Remarks
3.3.3.2. Propulsion Direction by Driver
Shift lever position by driver operation
Values
Remarks
3.3.3.3. Immobilization Status
Output EPB and Shift-P status
Values
<Primary>
<Secondary>
Remarks
3.3.3.4. Immobilization Request by Driver
Driver operation of EPB switch
Values
Remarks
3.3.3.5. Standstill Status
Vehicle stationary status
Values
Remarks
3.3.3.6. Estimated_Coasting_Rate
Estimated vehicle deceleration when throttle is closed
Values
[unit: m/s2]
Remarks
3.3.3.7. Estimated_Max_Accel_Capability
Estimated maximum acceleration
Values
[unit: m/s2]
Remarks
3.3.3.8. Estimated_Max_Decel_Capability
Estimated maximum deceleration
Values
Remarks
3.3.3.9. Estimated_Road_Wheel_Angle_Actual
Front wheel steer angle
Values
Remarks
3.3.3.10. Estimated_Road_Wheel_Angle_Rate_Actual
Front wheel steer angle rate
Values
Remarks
3.3.3.11. Steering_Wheel_Angle_Actual
Steering wheel angle
Values
Remarks
3.3.3.12. Steering_Wheel_Angle_Rate_Actual
Steering wheel angle rate
Values
Remarks
3.3.3.13. Current_Road_Wheel_Angle_Rate_Limit
Road wheel angle rate limit
Values
Remarks
Calculated from the “vehicle speed−steering angle rate” chart like below A) At a very low speed or stopped situation, use fixed value of 0.4 [rad/s] B) At a higher speed, the steering angle rate is calculated from the vehicle speed using 2.94 m/s3
The threshold speed between A and B is 10 [km/h] (
3.3.3.14. Estimated_Max_Lateral_Acceleration_Capability
Estimated max lateral acceleration
Values
2.94 [unit: m/s2] fixed value
Remarks
3.3.3.15. Estimated_Max_Lateral_Acceleration_Rate_Capability
Estimated max lateral acceleration rate
Values
2.94 [unit: m/s3] fixed value
Remarks
3.3.3.16. Accelerator Pedal Position
Position of the accelerator pedal (How much is the pedal depressed?)
Values
0 to 100 [unit: %]
Remarks
The accelerator position signal after zero point calibration is transmitted.
Transmitted failsafe value (0xFF)
3.3.3.17. Accelerator_Pedal_Intervention
This signal shows whether the accelerator pedal is depressed by a driver (intervention).
Values
Remarks
When the requested acceleration from depressed acceleration pedal is higher than the requested acceleration from system (ADS, PCS etc.), this signal will turn to “Beyond autonomy acceleration”.
Detail design (
3.3.3.18. Brake_Pedal_Position
Position of the brake pedal (How much is the pedal depressed?)
Values
0 to 100 [unit: %]
Remarks
Transmitted failsafe value (0xFF)
3.3.3.19. Brake_Pedal_Intervention
This signal shows whether the brake pedal is depressed by a driver (intervention).
Values
Remarks
Detail design (
3.3.3.20. Steering_Wheel_Intervention
This signal shows whether the steering wheel is turned by a driver (intervention).
Values
Remarks
3.3.3.21. Shift_Lever_Intervention
This signal shows whether the shift lever is controlled by a driver (intervention).
Values
Remarks
3.3.3.22. WheelSpeed_FL, WheelSpeed_FR, WheelSpeed_RL, WheelSpeed_RR
wheel speed value
Values
Remarks
3.3.3.23. WheelSpeed_FL_Rotation, WheelSpeed_FR_Rotation, WheelSpeed_RL_Rotation, WheelSpeed_RR_Rotation
Rotation direction of each wheel
Values
Remarks
3.3.3.24. Actual_Moving_Direction
Rotation direction of wheel
Values
Remarks
3.3.3.25. Longitudinal_Velocity
Estimated longitudinal velocity of vehicle
Values
Remarks
3.3.3.26. Longitudinal_Acceleration
Estimated longitudinal acceleration of vehicle
Values
Remarks
3.3.3.27. Lateral_Acceleration
Sensor value of lateral acceleration of vehicle
Values
Remarks
3.3.3.28. Yawrate
Sensor value of Yaw rate
Values
Remarks
3.3.3.29. Autonomy_State
State of whether autonomy mode or manual mode
Values
Remarks
3.3.3.30. Autonomy_Ready
Situation of whether the vehicle can transition to autonomy mode or not
Values
Remarks
Please see the summary of conditions.
3.3.3.31. Autonomy_Fault
Status of whether the fault regarding a functionality in autonomy mode occurs or not
Values
Remarks
3.4. APIs for BODY control
3.4.1. Functions
T.B.D.
3.4.2. Inputs
3.4.2.1. Turnsignallight_Mode_Command
Command to control the turnsignallight mode of the vehicle platform
Values
Remarks
T.B.D.
Detailed Design
When Turnsignallight_Mode_Command=1, vehicle platform sends left blinker on request.
When Turnsignallight_Mode_Command=2, vehicle platform sends right blinker on request.
3.4.2.2. Headlight_Mode_Command
Command to control the headlight mode of the vehicle platform
Values
Remarks
3.4.2.3. Hazardlight_Mode_Command
Command to control the hazardlight mode of the vehicle platform
Values
Remarks
3.4.2.4. Horn Pattern Command
Command to control the pattern of horn ON-time and OFF-time per cycle of the vehicle platform
Values
Remarks
3.4.2.5. Horn_Number_of_Cycle_Command
Command to control the Number of horn ON/OFF cycle of the vehicle platform
Values
0˜7 [−]
Remarks
3.4.2.6. Horn_Continuous_Command
Command to control of horn ON of the vehicle platform
Values
Remarks
3.4.2.7. Windshieldwiper_Mode_Front_Command
Command to control the front windshield wiper of the vehicle platform
Values
Remarks
3.4.2.8. Windshieldwiper_Intermittent_Wiping_Speed_Command
Command to control the Windshield wiper actuation interval at the Intermittent mode
Values
Remarks
3.4.2.9. Windshieldwiper_Mode_Rear_Command
Command to control the rear windshield wiper mode of the vehicle platform
Values
Remarks
3.4.2.10. Hvac_1 st_Command
Command to start/stop 1st row air conditioning control
Values
Remarks
Therefore, in order to control 4 (four) hvacs (1st_left/right, 2nd_left/right) individually, VCIB achieves the following procedure after Ready-ON. (This functionality will be implemented from the CV.)
3.4.2.11. Hvac_2nd_Command
Command to start/stop 2nd row air conditioning control
Values
Remarks
3.4.2.12. Hvac_TargetTemperature_1st_Left_Command
Command to set the target temperature around front left area
Values
Remarks
3.4.2.13. Hvac_TargetTemperature_1st_Right_Command
Command to set the target temperature around front right area
Values
Remarks
3.4.2.14. Hvac_TargetTemperature_2nd_Left_Command
Command to set the target temperature around rear left area
Values
Remarks
3.4.2.15. Hvac_TargetTemperature_2nd_Right_Command
Command to set the target temperature around rear right area
Values
Remarks
3.4.2.16. Hvac_Fan_Level_1st_Row_Command
Command to set the fan level on the front AC
Values
Remarks
3.4.2.17. Hvac_Fan_Level_2nd_Row_Command
Command to set the fan level on the rear AC
Values
Remarks
3.4.2.18. Hvac_1st_Row_AirOutlet_Mode_Command
Command to set the mode of 1st row air outlet
Values
Remarks
3.4.2.19. Hvac_2nd_Row_AirOutlet_Mode_CommandCommand to set the mode of 2nd row air outlet
Values
Remarks
3.4.2.20. Hvac_Recirculate_Command
Command to set the air recirculation mode
Values
Remarks
3.4.2.21. Hvac_AC_Command
Command to set the AC mode
Values
Remarks
3.4.3. Outputs
3.4.3.1. Turnsignallight_Mode_Status
Status of the current turnsignallight mode of the vehicle platform
Values
Remarks
3.4.3.2. Headlight_Mode_Status
Status of the current headlight mode of the vehicle platform
Values
Remarks
N/A
Detailed Design
3.4.3.3. Hazardlight_Mode_Status
Status of the current hazard lamp mode of the vehicle platform
Values
Remarks
N/A
3.4.3.4. Horn_Status
Status of the current horn of the vehicle platform
Values
Remarks
3.4.3.5. Windshieldwiper_Mode_Front_Status
Status of the current front windshield wiper mode of the vehicle platform
Values
Remarks
Fail Mode Conditions
3.4.3.6. Windshieldwiper_Mode_Rear_Status
Status of the current rear windshield wiper mode of the vehicle platform
Values
Remarks
3.4.3.7. Hvac_1st_Status
Status of activation of the 1st row HVAC
Values
Remarks
3.4.3.8. Hvac_2 nd_Status
Status of activation of the 2nd row HVAC
Values
Remarks
3.4.3.9. Hvac_Temperature_1st_Left_Status
Status of set temperature of 1st row left
Values
Remarks
3.4.3.10. Hvac_Temperature_1st_Right_Status
Status of set temperature of 1st row right
Values
Remarks
3.4.3.11. Hvac_Temperature_2nd_Left_Status
Status of set temperature of 2nd row left
Values
Remarks
3.4.3.12. Hvac_Temperature_2nd_Right_Status
Status of set temperature of 2nd row right
Values
Remarks
3.4.3.13. Hvac_Fan_Level_1st_Row_Status
Status of set fan level of 1st row
Values
Remarks
3.4.3.14. Hvac_Fan_Level_2nd_Row_Status
Status of set fan level of 2nd row
Values
Remarks
3.4.3.15. Hvac_1st_Row_AirOutlet_Mode_Status
Status of mode of 1st row air outlet
Values
Remarks
3.4.3.16. Hvac_2nd_Row_AirOutlet_Mode_Status
Status of mode of 2nd row air outlet
Values
Remarks
3.4.3.17. Hvac Recirculate Status
Status of set air recirculation mode
Values
Remarks
3.4.3.18. Hvac_AC_Status
Status of set AC mode
Values
Remarks
3.4.3.19. 1st_Right_Seat_Occupancy_Status
Seat occupancy status in 1st left seat
Values
Remarks
When there is luggage on the seat, this signal may be set to “Occupied”.
3.4.3.20. 1st_Left_Seat_Belt_Status
Status of driver's seat belt buckle switch
Values
Remarks
It is checking to a person in charge, when using it. (Outputs “undetermined=10” as an initial value.)
3.4.3.21. 1st_Right_Seat_Belt_Status
Status of passenger's seat belt buckle switch
Values
Remarks
It is checking to a person in charge, when using it. (Outputs “undetermined=10” as an initial value.)
3.4.3.22. 2nd_Left_Seat_Belt_Status
Seat belt buckle switch status in 2nd left seat
Values
Remarks
3.4.3.23. 2nd_Right_Seat_Belt_Status
Seat belt buckle switch status in 2nd right seat
Values
Remarks
3.5. APIs for Power control
3.5.1. Functions
T.B.D.
3.5.2. Inputs
3.5.2.1. Power_Mode_Request
Command to control the power mode of the vehicle platform
Values
Remarks
The followings are the explanation of the three power modes, i.e. [Sleep][Wake][Driving Mode], which are controllable via API.
[Sleep]
Vehicle power off condition. In this mode, the high voltage battery does not supply power, and neither VCIB nor other VP ECUs are activated.
[Wake]
VCIB is awake by the low voltage battery. In this mode, ECUs other than VCIB are not awake except for some of the body electrical ECUs.
[Driving Mode]
Ready ON mode. In this mode, the high voltage battery supplies power to the whole VP and all the VP ECUs including VCIB are awake.
3.5.3. Outputs
3.5.3.1. Power_Mode_Status
Status of the current power mode of the vehicle platform
Values
Remarks
3.6. APIs for Safety
3.6.1. Functions
T.B.D.
3.6.2. Inputs
3.6.3. Outputs
3.6.3.1. Request for Operation
Request for operation according to status of vehicle platform toward ADS
Values
Remarks
3.6.3.2. Passive_Safety_Functions_Triggered
Crash detection Signal
Values
Remarks
Priority: crash detection>normal
Transmission interval is 100 ms within fuel cutoff motion delay allowance time (1 s) so that data can be transmitted more than 5 times. In this case, an instantaneous power interruption is taken into account.
3.6.3.3. Brake_System_Degradation_Modes
Indicate Brake_System status
Values
Remarks
3.6.3.4. Propulsive_System_Degradation_Modes
Indicate Powertrain_System status
Values
Remarks
3.6.3.5. Direction_Control_Degradation_Modes
Indicate Direction_Control status
Values
Remarks
3.6.3.6. WheelLock_Control Degradation Modes
Indicate WheelLock_Control status
Values
Remarks
3.6.3.7. Steering_System Degradation Modes
Indicate Steering_System status
Values
Remarks
3.6.3.8. Power_System_Degradation_Modes
[T.B.D]
3.6.3.9. Communication_Degradation_Modes
[T.B.D]
3.7. APIs for Security
3.7.1. Functions
T.B.D.
3.7.2. Inputs
3.7.2.1. 1st_Left_Door_Lock_Command, 1st_Right_Door_Lock_Command, 2nd Left Door_Lock_Command, 2nd_Right_Door_Lock_Command Command to control each door lock of the vehicle platform
Values
Remarks
3.7.2.2. Central_Vehicle_Lock_Exterior_Command
Command to control the all door lock of the vehicle platform.
Values
Remarks
3.7.3. Outputs
3.7.3.1. 1st_Left_Door_Lock_Status
Status of the current 1st-left door lock mode of the vehicle platform
Values
Remarks
3.7.3.2. 1st_Right_Door_Lock_Status
Status of the current 1st-right door lock mode of the vehicle platform
Remarks
3.7.3.3. 2nd_Left_Door_Lock_Status
Status of the current 2nd-left door lock mode of the vehicle platform
Values
Remarks
3.7.3.4. 2nd_Right_Door_Lock_Status
Status of the current 2nd-right door lock mode of the vehicle platform
Values
Remarks
3.7.3.5. Central_Vehicle_Exterior_Locked_Status
Status of the current all door lock mode of the vehicle platform
Values
Remarks
3.7.3.6. Vehicle Alarm Status
Status of the current vehicle alarm of the vehicle platform
Values
Remarks
N/A
3.8. APIs for MaaS Service
3.8.1. Functions
T.B.D.
3.8.2. Inputs
3.8.3. Outputs
Toyota's MaaS Vehicle Platform
Architecture Specification
[Standard Edition #0.1]
History of Revision
Index
1. General Concept
1.1. Purpose of this Specification
This document is an architecture specification of Toyota's MaaS Vehicle Platform and contains the outline of system in vehicle level.
1.2. Target Vehicle Type
This specification is applied to the Toyota vehicles with the electronic platform called 19ePF [ver.1 and ver.2].
The representative vehicle with 19ePF is shown as follows.
e-Palette, Sienna, RAV4, and so on.
1.3. Definition of Term
1.4. Precaution for Handling
This is an early draft of the document.
All the contents are subject to change. Such changes are notified to the users. Please note that some parts are still T.B.D. will be updated in the future.
2. Architectural Concept
2.1. Overall Structure of MaaS
The overall structure of MaaS with the target vehicle is shown (
Vehicle control technology is being used as an interface for technology providers.
Technology providers can receive open API such as vehicle state and vehicle control, necessary for development of automated driving systems.
2.2. Outline of System Architecture on the Vehicle
The system architecture on the vehicle as a premise is shown (
The target vehicle of this document will adopt the physical architecture of using CAN for the bus between ADS and VCIB. In order to realize each API in this document, the CAN frames and the bit assignments are shown in the form of “bit assignment chart” as a separate document.
2.3. Outline of Power Supply Architecture on the Vehicle
The power supply architecture as a premise is shown as follows (
The blue colored parts are provided from an ADS provider. And the orange colored parts are provided from the VP.
The power structure for ADS is isolate from the power structure for VP. Also, the ADS provider should install a redundant power structure isolated from the VP.
3. Safety Concept
3.1. Overall Safety Concept
The basic safety concept is shown as follows.
The strategy of bringing the vehicle to a safe stop when a failure occurs is shown as follows (
1. After occurrence of a failure, the entire vehicle executes “detecting a failure” and “correcting an impact of failure” and then achieves the safety state 1.
2. Obeying the instructions from the ADS, the entire vehicle stops in a safe space at a safe speed (assumed less than 0.2 G).
However, depending on a situation, the entire vehicle should happen a deceleration more than the above deceleration if needed.
3. After stopping, in order to prevent slipping down, the entire vehicle achieves the safety state 2 by activating the immobilization system.
See the separated document called “Fault Management” regarding notifiable single failure and expected behavior for the ADS.
3.2. Redundancy
The redundant functionalities with Toyota's MaaS vehicle are shown.
Toyota's Vehicle Platform has the following redundant functionalities to meet the safety goals led from the functional safety analysis.
Redundant Braking
Any single failure on the Braking System doesn't cause loss of braking functionality. However, depending on where the failure occurred, the capability left might not be equivalent to the primary system's capability. In this case, the braking system is designed to prevent the capability from becoming 0.3 G or less.
Redundant Steering
Any single failure on the Steering System doesn't cause loss of steering functionality. However, depending on where the failure occurred, the capability left might not be equivalent to the primary system's capability. In this case, the steering system is designed to prevent the capability from becoming 0.3 G or less.
Redundant Immobilization
Toyota's MaaS vehicle has 2 immobilization systems, i.e. P lock and EPB. Therefore, any single failure of immobilization system doesn't cause loss of the immobilization capability. However, in the case of failure, maximum stationary slope angle is less steep than when the systems are healthy.
Redundant Power
Any single failure on the Power Supply System doesn't cause loss of power supply functionality. However, in case of the primary power failure, the secondary power supply system keeps supplying power to the limited systems for a certain time.
Redundant Communication
Any single failure on the Communication System doesn't cause loss of all the communication functionality. System which needs redundancy has physical redundant communication lines. For more detail information, see the chapter “Physical LAN architecture (in-Vehicle)”.
4. Security Concept
4.1. Outline
Regarding security, Toyota's MaaS vehicle adopts the security document issued by Toyota as an upper document.
4.2. Assumed Risks
The entire risk includes not only the risks assumed on the base e-PF but also the risks assumed for the Autono-MaaS vehicle.
The entire risk is shown as follows.
[Remote Attack]
[Modification]
4.3. Countermeasure for the Risks
The countermeasure of the above assumed risks is shown as follows.
4.3.1. The Countermeasure for a Remote Attack
The countermeasure for a remote attack is shown as follows.
Since the autonomous driving kit communicates with the center of the operation entity, end-to-end security should be ensured. Since a function to provide a travel control instruction is performed, multi-layered protection in the autonomous driving kit is required. Use a secure microcomputer or a security chip in the autonomous driving kit and provide sufficient security measures as the first layer against access from the outside. Use another secure microcomputer and another security chip to provide security as the second layer. (Multi-layered protection in the autonomous driving kit including protection as the first layer to prevent direct entry from the outside and protection as the second layer as the layer below the former)
4.3.2. The Countermeasure for a Modification
The countermeasure for a modification is shown as follows.
For measures against a counterfeit autonomous driving kit, device authentication and message authentication are carried out. In storing a key, measures against tampering should be provided and a key set is changed for each pair of a vehicle and an autonomous driving kit. Alternatively, the contract should stipulate that the operation entity exercise sufficient management so as not to allow attachment of an unauthorized kit. For measures against attachment of an unauthorized product by an Autono-MaaS vehicle user, the contract should stipulate that the operation entity exercise management not to allow attachment of an unauthorized kit.
In application to actual vehicles, conduct credible threat analysis together, and measures for addressing most recent vulnerability of the autonomous driving kit at the time of LO should be completed.
5. Function Allocation
5.1. In a Healthy Situation
The allocation of representative functionalities is shown as below (
[Function Allocation]
5.2. In a Single Failure
See the separated document called “Fault Management” regarding notifiable single failure and expected behavior for the ADS.
Though embodiments of the present disclosure have been described above, it should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-015715 | Jan 2020 | JP | national |
