Patent Application
20220105954
Embodiments generally relate to vehicle platoons. More particularly, embodiments relate to cascaded connection technology for vehicle platoons.
Vehicle platooning is a technique to organize highway traffic into groups of close-following vehicles. The lead vehicle is generally operated by a human driver, whereas the following vehicles are operated by an autonomous driving system. In such a case, the lead vehicle might broadcast driving instructions to the following vehicles, control participation (e.g., joining, departing) in the platoon, and so forth. The communication range of the lead vehicle may be limited depending on the height of the vehicle, packet error rate constraints, and type of wireless link being used. Indeed, relatively low-height vehicles such as sedans typically have communication ranges that in turn limit the maximum size of the platoon. While improving antenna designs may increase the communication range, such a solution may involve costly changes to the exterior design of the vehicle and may have a negative impact on aerodynamics (e.g., drag). Moreover, other information transfer solutions such as wireless relaying may increase latency, which gives rise to safety concerns.
The various advantages of the embodiments will become apparent to one skilled in the art by reading the following specification and appended claims, and by referencing the following drawings, in which:
Turning now to
Similarly, a second platoon 14 (14a-14c) is positioned ahead of the first platoon 12 and also travels from left to right. In an embodiment, a second lead vehicle 14a (e.g., Leading P vehicle) is manually operated by a human, whereas remaining vehicles 14b, 14c are operated in an autonomous mode. In the illustrated example, the second lead vehicle 14a has a communication range 18 that enables the second lead vehicle 14a to broadcast operation instructions to the remaining vehicles 14b, 14c, so that the occupants of the remaining vehicles 14b, 14c may rest, enjoy entertainment, etc., as if they were passengers of the second lead vehicle 14a. In the conventional scenario 10, however, highway throughput is suboptimal because the first platoon 12 is separate from the second platoon 14 and maintains a relatively large following distance for safety concerns.
By contrast, in an enhanced scenario 20, the first lead vehicle 12a automatically determines based on the communication range 18 of the second lead vehicle 14a that a direct communications link can be established between the first lead vehicle 12a and the second lead vehicle 14a. Accordingly, the first lead vehicle 12a joins the second platoon 14 so that the first platoon 12 and the second platoon 14 constitute a “cascaded” platoon. In such a case, the second lead vehicle 14a broadcasts operation instructions 22 to the remaining vehicles 14b, 14c and the first lead vehicle 12a, which transitions into the autonomous mode while the cascaded platoon is in existence. The first lead vehicle 12a then broadcasts the operation instructions 22 to the remaining vehicles 12b-12d in the first platoon 12.
The enhanced scenario 20 therefore enables larger platoons to be formed, which increases highway throughput, increases fuel economy, reduces emissions, and improves the riding experience. Additionally, latency is minimized because the number of “hops” from the second lead vehicle 14a to the rest of the cascaded platoon is at most two. Latency may be further reduced by enabling the first lead vehicle 12a to control participation in the first platoon 12 locally at the first lead vehicle 12a and without the involvement of the second lead vehicle 14a. The enhanced scenario 20 also eliminates any need to modify antennas or vehicle exteriors. Accordingly, cost savings may be achieved and a negative impact on aerodynamics is avoided.
For example, computer program code to carry out operations shown in the method 30 may be written in any combination of one or more programming languages, including an object oriented programming language such as JAVA, SMALLTALK, C++ or the like and conventional procedural programming languages, such as the “C” programming language or similar programming languages. Additionally, logic instructions might include assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, state-setting data, configuration data for integrated circuitry, state information that personalizes electronic circuitry and/or other structural components that are native to hardware (e.g., host processor, central processing unit/CPU, microcontroller, etc.).
Illustrated processing block 32 sends first operation instructions (e.g., driving instructions) to a first platoon of autonomous vehicles positioned behind the first lead vehicle, wherein the first operation instructions correspond to a manual operation of the first lead vehicle. A direct communications link may be established at block 34 between the first lead vehicle and a second lead vehicle positioned ahead of the first lead vehicle, wherein the second lead vehicle is associated with a second platoon of autonomous vehicles. As will be discussed in greater detail, block 34 may include detecting the second lead vehicle based on a roadside broadcast message and exchanging, via a service channel (SCH), a set of connection messages with the second lead vehicle to establish the direct communications link. In an embodiment, block 34 also includes confirming the range suitability of the direct communications link based on the roadside message. Block 34 may also include using adaptive cruise control (ACC) to reduce the distance between the first lead vehicle and the last vehicle in the second platoon (e.g., a gap of 35 m at a velocity of 35 m/s).
Block 36 provides for broadcasting second operation instructions from the direct communications link to the first platoon of autonomous vehicles while the first lead vehicle is in the autonomous mode. In the illustrated example, the second operation instructions correspond to the manual operation of the second lead vehicle. In an embodiment, the first operation instructions and the second operation instructions are driving instructions sent via a control channel. Block 38 may control participation in the first platoon of vehicles locally at the first lead vehicle while the first lead vehicle is in the autonomous mode. Such an approach may further reduce latency, as already noted. Illustrated block 40 exchanges, via a service channel, a set of dismission messages with the second lead vehicle to discontinue the direct communications link between the first lead vehicle and the second lead vehicle.
The illustrated method 30 therefore enables larger platoons to be formed, which increases highway throughput, increases fuel economy, reduces emissions, and improves the riding experience. Additionally, latency is minimized because the number of hops from the second lead vehicle to the rest of the cascaded platoon is at most two. Latency may be further reduced by enabling the first lead vehicle to control participation in the first platoon locally at the first lead vehicle and without the involvement of the second lead vehicle. The method 30 also eliminates any need to modify antennas or vehicle exteriors. Accordingly, cost savings may be achieved and a negative impact on aerodynamics may be avoided. In one example, the messages described herein are carried through a vehicular ad-hoc network (VANET) and/or wireless access for vehicular environments (WAVE) basic service set (WBSS).
In Table I, S* is an operating instruction message transferred in a single hop from the second lead vehicle to following vehicles in the second platoon; M* is an operating instruction message transferred by multi-hop from the second lead vehicle to following vehicles in the first platoon; and S** are internal platoon maneuver messages (e.g., for platoon participation changes such as join/leave) transferred in a single hop from following vehicles of a platoon and are handled by the respective lead vehicle (e.g., either the first lead vehicle or the second lead vehicle).
Illustrated processing block 52 confirms traffic suitability at the Leading F vehicle. In an embodiment, block 52 includes checking platoon size, ensuring that no platoon participation changes are ongoing, and so forth. Platoon participation changes are blocked/prevented at processing block 54, wherein block 56 causes the Leading F vehicle to come within the CCH range of the Leading P vehicle. In block 58, the Leading P vehicle and the Leading F vehicle join a WBSS. The Leading F vehicle may send a connection request message 60 on the SCH (e.g., via a direct communications link) to the Leading P, which confirms traffic suitability at block 62 in response to the message 60. Additionally, the Leading P vehicle may block platoon participation changes at processing block 64. The illustrated Leading P vehicle acknowledges the request message 60 via a connection approval message 66 on the SCH.
The Leading P may also periodically issue operation instructions 68 to the Leading F vehicle on the CCH. The Leading F vehicle confirms at block 70 that the operation instructions 68 can be received periodically from the Leading P vehicle and transitions to autonomous mode (e.g., initiates automated driving cooperative adaptive cruise control/CACC) at block 72. The Leading F vehicle then sends a connection done message 74 to the Leading P vehicle on the SCH. Additionally, processing block 76 unblocks/permits platoon participation changes at the Leading F vehicle and processing block 78 unblocks platoon participation changes at the Leading P vehicle.
Exceptions
If it is determined at block 52 that the traffic conditions are not suitable, the Leading F vehicle may abort the procedure and check the status again later. Additionally, if it is determined at block 62 that the traffic conditions are not suitable, the Leading P vehicle may send a connection rejected message (not shown) to the Leading F vehicle to restart the procedure. In an embodiment, if it is determined at block 70 that the operation instructions 68 cannot or have not been received, the Leading F vehicle may decelerate and maintain a safe distance from the platoon ahead. Moreover, the Leading P vehicle may treat a failure to receive the connection done message 74, as a failed establishment of the cascaded connection.
Illustrated processing block 82 confirms that no platoon participation changes are ongoing, wherein platoon participation changes are blocked at processing block 84. The Leading F vehicle may send a dismission request 86 to the Leading P vehicle, which confirms that no platoon participation changes are ongoing at block 88 in response to the dismission request 86.
The Leading P vehicle also blocks platoon participation changes at processing block 90. The Leading P vehicle may then send a dismission approval message 92 on the SCH to the Leading F vehicle, followed by an operation instruction 94 on the CCH to the Leading F vehicle. In an embodiment, the operation instruction 94 includes a deceleration request or command. Upon receiving the operation instruction 94, the Leading F vehicle decelerates to a safe distance from the second platoon at block 96. Additionally, the illustrated Leading F vehicle sends a dismission done message 98 on the SCH to the Leading P vehicle. Block 100 may transition the Leading F vehicle to manual mode (e.g., permitting a human to drive the Leading F vehicle). Additionally, processing block 102 unblocks platoon participation changes at the Leading F vehicle and processing block 104 unblocks platoon participation changes at the Leading P vehicle.
Exceptions
If it is determined at block 82 that platoon participation changes are ongoing, the Leading F vehicle checks again several or tens of milliseconds later to start the dismission again. Additionally, if it is determined at block 88 that platoon participation changes are ongoing, the Leading P vehicle rejects the dismission request 86 by sending a dismission rejection message (not shown) on the SCH to the Leading F vehicle. In such a case, the Leading F vehicle would start the dismission again later. Moreover, even if the Leading P vehicle does not receive the dismission done message 98, the Leading P vehicle may assume that the dismission is complete.
Assuming that the CCH range is 100 m, then the platoon size will be 4. Without a cascaded connection of vehicle platoon, the throughput is 2367 vehicles per hour. With a cascaded connection of two vehicle platoons, the platoon size is equally increased to seven, and the throughput is 2988 vehicles per hour, which means that the throughput is improved by 26%. With a cascaded connection of four vehicle platoons, the platoon size is equally increased to thirteen, and the throughput is almost improved by about 50% to 3563 vehicles per hour.
Latency Reduction to 1/(N−1)
With cascaded platoons, the latency of information flow from the leader to the farthest follower is significantly reduced (e.g., close to 1/(N−1) for the farthest follower) relative to a pure predecessor-following platoon approach (e.g., wireless relay with N being the number of vehicles in single platoon of a cascaded group). In the following example, the number of hops for information flow is reduced from six to two, and latency will be reduced accordingly.
In the case of a predecessor-following topology with one leader and six followers, there are six hops from leader to the last follower.
In the cascaded connection technology described herein, there are only two hops from the Leading P vehicle (e.g., second lead vehicle) to the last follower (i.e., the leftmost vehicle).
Generally speaking, for a platoon group of (M−1)*(N−1)+N vehicles (M, the number of platoons; N, the size of single platoon), there are M hops from the leading P to the last follower. By contrast, for a predecessor-following topology of (M−1)*(N−1)+N vehicles, there are N*M−M hops from the leader to the last follower. Therefore, the number of hops is reduced to M/(M*N−M), close to 1/(N−1), compared to the predecessor-following topology. Accordingly, the latency is also reduced close to 1/(N−1) of that of predecessor-following topology.
Turning now to
In one embodiment, the transceiver 126 communicates via dedicated short-range communication (DSRC) and/or VANET, using an IEEE (Institute of Electrical and Electronics Engineers) 802.11p protocol at the physical layer. In such a case, a 75 MHz band might be allocated around the 5.9 GHz frequency, with the 75 MHz band including one CCH, six SCHs and one 5 MHz reserved channel. The transceiver 126 may also include an on board unit (OBU) that listens to the CCH every few tens or hundreds of milliseconds to detect safety messages.
The host processor 114 may include logic 132 (e.g., logic instructions, configurable logic, fixed-functionality hardware logic, etc., or any combination thereof) to perform one or more aspects of the method 30 (
The vehicle 110 may therefore be considered performance-enhanced to the extent that it enables larger platoons to be formed, which increases highway throughput, increases fuel economy, reduces emissions, and improves the riding experience. Additionally, latency is minimized because the number of hops from the vehicle 110 to the rest of the cascaded platoon is at most two. Latency may be further reduced by enabling the vehicle 110 to control participation in the first platoon locally at the first lead vehicle and without the involvement of the second lead vehicle. The logic 132 also eliminates any need to modify antennas or vehicle exteriors. Accordingly, cost savings may be achieved and a negative impact on aerodynamics may be avoided. Although the logic 132 is illustrated in the host processor 114, the logic 132 may be located elsewhere in the vehicle 110. For example, the logic 132 might include instructions that are retrieved from the system memory 118 and/or the mass storage 130.
The logic 146 may be implemented at least partly in configurable logic or fixed-functionality hardware logic. In one example, the logic 146 includes transistor channel regions that are positioned (e.g., embedded) within the substrate(s) 144. Thus, the interface between the logic 146 and the substrate(s) 144 may not be an abrupt junction. The logic 146 may also be considered to include an epitaxial layer that is grown on an initial wafer of the substrate(s) 174.
Example 1 includes a vehicle subsystem comprising an antenna, a transceiver coupled to the antenna, a processor coupled to the transceiver, and a memory including a set of instructions, which when executed by the processor, cause the vehicle subsystem to send first operation instructions to a first platoon of autonomous vehicles positioned behind a first lead vehicle, wherein the first operation instructions correspond to a manual operation of the first lead vehicle, establish a direct communications link between the first lead vehicle and a second lead vehicle positioned ahead of the first lead vehicle, wherein the second lead vehicle is to be associated with a second platoon of autonomous vehicles, and broadcast second operation instructions from the direct communications link to the first platoon of autonomous vehicles while the first lead vehicle is in an autonomous mode, wherein the second operation instructions correspond to a manual operation of the second lead vehicle.
Example 2 includes the vehicle subsystem of Example 1, wherein the instructions, when executed, cause the first lead vehicle to control participation in the first platoon of vehicles locally at the first lead vehicle while the first lead vehicle is in the autonomous mode.
Example 3 includes the vehicle subsystem of Example 1, wherein the instructions, when executed, cause the first lead vehicle to detect the second lead vehicle based on a roadside broadcast message, and exchange, via a service channel, a set of connection messages with the second lead vehicle to establish the direct communications link.
Example 4 includes the vehicle subsystem of Example 3, wherein the instructions, when executed, cause the first lead vehicle to confirm a range suitability of the direct communications link based on the roadside message.
Example 5 includes the vehicle subsystem of any one of Examples 1 to 4, wherein the first operation instructions and the second operation instructions are to be sent via a control channel.
Example 6 includes the vehicle subsystem of Example 1, wherein the instructions, when executed, cause the first lead vehicle to exchange, via a service channel, a set of dismission messages with the second lead vehicle to discontinue the direct communications link between the first lead vehicle and the second lead vehicle.
Example 7 includes a semiconductor apparatus comprising one or more substrates, and logic coupled to the one or more substrates, wherein the logic is implemented at least partly in one or more of configurable logic or fixed-functionality hardware logic, the logic coupled to the one or more substrates to send first operation instructions to a first platoon of autonomous vehicles positioned behind the first lead vehicle, wherein the first operation instructions correspond to a manual operation of the first lead vehicle, establish a direct communications link between the first lead vehicle and a second lead vehicle positioned ahead of the first lead vehicle, wherein the second lead vehicle is to be associated with a second platoon of autonomous vehicles, and broadcast second operation instructions from the direct communications link to the first platoon of autonomous vehicles while the first lead vehicle is in an autonomous mode, wherein the second operation instructions correspond to a manual operation of the second lead vehicle.
Example 8 includes the semiconductor apparatus of Example 7, wherein the logic coupled to the one or more substrates is to control participation in the first platoon of vehicles locally at the first lead vehicle while the first lead vehicle is in the autonomous mode.
Example 9 includes the semiconductor apparatus of Example 7, wherein the logic coupled to the one or more substrates is to detect the second lead vehicle based on a roadside broadcast message, and exchange, via a service channel, a set of connection messages with the second lead vehicle to establish the direct communications link.
Example 10 includes the semiconductor apparatus of Example 8, wherein the logic coupled to the one or more substrates is to confirm a range suitability of the direct communications link based on the roadside message.
Example 11 includes the semiconductor apparatus of any one of Examples 7 to 10, wherein the first operation instructions and the second operation instructions are to be sent via a control channel.
Example 12 includes the semiconductor apparatus of Example 7, wherein the logic coupled to the one or more substrates is to exchange, via a service channel, a set of dismission messages with the second lead vehicle to discontinue the direct communications link between the first lead vehicle and the second lead vehicle.
Example 13 includes at least one computer readable storage medium comprising a set of instructions, which when executed by a first lead vehicle, cause the first lead vehicle to send first operation instructions to a first platoon of autonomous vehicles positioned behind the first lead vehicle, wherein the first operation instructions correspond to a manual operation of the first lead vehicle, establish a direct communications link between the first lead vehicle and a second lead vehicle positioned ahead of the first lead vehicle, wherein the second lead vehicle is to be associated with a second platoon of autonomous vehicles, and broadcast second operation instructions from the direct communications link to the first platoon of autonomous vehicles while the first lead vehicle is in an autonomous mode, wherein the second operation instructions correspond to a manual operation of the second lead vehicle.
Example 14 includes the at least one computer readable storage medium of Example 13, wherein the instructions, when executed, cause the first lead vehicle to control participation in the first platoon of vehicles locally at the first lead vehicle while the first lead vehicle is in the autonomous mode.
Example 15 includes the at least one computer readable storage medium of Example 13, wherein the instructions, when executed, cause the first lead vehicle to detect the second lead vehicle based on a roadside broadcast message, and exchange, via a service channel, a set of connection messages with the second lead vehicle to establish the direct communications link.
Example 16 includes the at least one computer readable storage medium of Example 15, wherein the instructions, when executed, cause the first lead vehicle to confirm a range suitability of the direct communications link based on the roadside message.
Example 17 includes the at least one computer readable storage medium of any one of Examples 13 to 16, wherein the first operation instructions and the second operation instructions are to be sent via a control channel.
Example 18 includes the at least one computer readable storage medium of Example 13, wherein the instructions, when executed, cause the first lead vehicle to exchange, via a service channel, a set of dismission messages with the second lead vehicle to discontinue the direct communications link between the first lead vehicle and the second lead vehicle.
Example 19 includes a method of operating a first lead vehicle, comprising sending first operation instructions to a first platoon of autonomous vehicles positioned behind the first lead vehicle, wherein the first operation instructions correspond to a manual operation of the first lead vehicle, establishing a direct communications link between the first lead vehicle and a second lead vehicle positioned ahead of the first lead vehicle, wherein the second lead vehicle is associated with a second platoon of autonomous vehicles, and broadcasting second operation instructions from the direct communications link to the first platoon of autonomous vehicles while the first lead vehicle is in an autonomous mode, wherein the second operation instructions correspond to a manual operation of the second lead vehicle.
Example 20 includes the method of Example 19, further including controlling participation in the first platoon of vehicles locally at the first lead vehicle while the first lead vehicle is in the autonomous mode.
Example 21 includes the method of Example 19, wherein establishing the direct communications link includes detecting the second lead vehicle based on a roadside broadcast message, and exchanging, via a service channel, a set of connection messages with the second lead vehicle.
Example 22 includes the method of Example 21, further including confirming a range suitability of the direct communications link based on the roadside broadcast message.
Example 23 includes the method of any one of Examples 19 to 22, wherein the first operation instructions and the second operation instructions are sent via a control channel.
Example 24 includes the method of Example 19, further including exchanging, via a service channel, a set of dismission messages with the second lead vehicle to discontinue the direct communications link between the first lead vehicle and the second lead vehicle.
Example 25 includes means for performing the method of any one of Examples 19 to 24.
Thus, technology described herein significantly improves traffic throughput and reduces latency in the flow of information from the leader to the farthest follower. Moreover, the technology requires no change in antenna or vehicle exterior design.
Embodiments are applicable for use with all types of semiconductor integrated circuit (“IC”) chips. Examples of these IC chips include but are not limited to processors, controllers, chipset components, programmable logic arrays (PLAs), memory chips, network chips, systems on chip (SoCs), SSD/NAND controller ASICs, and the like. In addition, in some of the drawings, signal conductor lines are represented with lines. Some may be different, to indicate more constituent signal paths, have a number label, to indicate a number of constituent signal paths, and/or have arrows at one or more ends, to indicate primary information flow direction. This, however, should not be construed in a limiting manner. Rather, such added detail may be used in connection with one or more exemplary embodiments to facilitate easier understanding of a circuit. Any represented signal lines, whether or not having additional information, may actually comprise one or more signals that may travel in multiple directions and may be implemented with any suitable type of signal scheme, e.g., digital or analog lines implemented with differential pairs, optical fiber lines, and/or single-ended lines.
Example sizes/models/values/ranges may have been given, although embodiments are not limited to the same. As manufacturing techniques (e.g., photolithography) mature over time, it is expected that devices of smaller size could be manufactured. In addition, well known power/ground connections to IC chips and other components may or may not be shown within the figures, for simplicity of illustration and discussion, and so as not to obscure certain aspects of the embodiments. Further, arrangements may be shown in block diagram form in order to avoid obscuring embodiments, and also in view of the fact that specifics with respect to implementation of such block diagram arrangements are highly dependent upon the platform within which the embodiment is to be implemented, i.e., such specifics should be well within purview of one skilled in the art. Where specific details (e.g., circuits) are set forth in order to describe example embodiments, it should be apparent to one skilled in the art that embodiments can be practiced without, or with variation of, these specific details. The description is thus to be regarded as illustrative instead of limiting.
The term “coupled” may be used herein to refer to any type of relationship, direct or indirect, between the components in question, and may apply to electrical, mechanical, fluid, optical, electromagnetic, electromechanical or other connections. In addition, the terms “first”, “second”, etc. may be used herein only to facilitate discussion, and carry no particular temporal or chronological significance unless otherwise indicated.
As used in this application and in the claims, a list of items joined by the term “one or more of” may mean any combination of the listed terms. For example, the phrases “one or more of A, B or C” may mean A, B, C; A and B; A and C; B and C; or A, B and C.
Those skilled in the art will appreciate from the foregoing description that the broad techniques of the embodiments can be implemented in a variety of forms. Therefore, while the embodiments have been described in connection with particular examples thereof, the true scope of the embodiments should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification, and following claims.
The present application is a National Stage Patent Application claiming the benefit of priority to International Application No. PCT/CN2019/077773 filed on Mar. 21, 2019.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2019/077773 | 3/12/2019 | WO | 00 |
