The subject matter of the present disclosure broadly relates to the art of vehicle tire assemblies that include internal inflation height and contact patch sensors operative to generate signals, data, information and/or other outputs having a relation to an inflated height of the associated tire assembly and/or having a relation to the contact patch defined between the tread of the associated tire assembly and a roadway or other support surface on which the tire assembly is supported. Such sensors use millimeter wave radar technology of an predetermined frequency and wavelength and/or within a predetermined range of frequencies and wavelengths. Tire assemblies including such millimeter wavelength radar inflation height and contact patch sensors as well vehicle systems including one or more of such tire assemblies are also included.
It will be appreciated that the subject matter of the present disclosure may be particularly amenable to use in connection with vehicles, including motorized vehicles such as cars, trucks, and buses and also unmotorized vehicles such as trailers or the like, and the subject matter hereof will be discussed in detail with specific reference to such vehicles. However, it is to be specifically understood that application and use of the subject sensors is not intended to be in any way limited to the specific examples disclosed herein, which are merely exemplary.
It is generally known to include one or more sensors inside of a tire body and/or as part of a tire assembly, such as connected to a wheel and located in an air chamber of a pneumatic tire. Such sensors have included optical sensors, ultrasonic sensors, and other non-contact distance sensors. In many cases, such system have been deemed to be suboptimal for a wide variety of different reasons such as low resolution, slow update and/or refresh rates, ineffectiveness due to the conditions inside the tire chamber, and other drawbacks such as the inability to derive the data needed for use in modern vehicle control systems.
One such prior system uses an ultrawideband radar sensor inside of a tire chamber. The sensor uses radar waves to sense the condition of the soil beneath the tire, to sense the tire footprint, and/or to sense deflection of the tire casing. The ultrawideband radar waves are thought to be deficient in terms of the type, quality and speed of the data provided in terms of resolution, refresh rates, electronic interference, and the like. Also, one such prior system uses a slip ring to install the sensor such that it is continuously oriented vertically downward toward the surface on which the tire is rolling, and this slip ring system is not desirable for many applications due to a variety of know deficiencies.
Other known sensors are embedded in the casing of the tire, such as in the tread region or sidewall. These sensors can be effective for certain applications but require the tire, itself, to be manufactured with or modified to include the sensor(s), which increases the cost of the tires and prevents the re-use of sensors that are permanently embedded in the tire casing. These systems typically also lack a source of electrical power and require a fixed radio-frequency interrogator connected to the vehicle body or suspension to energize and activate the sensor.
Still other systems have relied upon placement of sensors external to the tire air chamber, such as on the vehicle suspension or body. Such systems attempt to sense the conditions inside the tire from outside the tire casing, which reduces their effectiveness and limits the type and quality of information provided.
Notwithstanding these conventional tire sensors and others that are known in the art, it is believed that a need exists to address the foregoing and/or other challenges while providing comparable or improved performance, ease of manufacture, reduced cost of manufacture, and/or otherwise advancing the art of tire assemblies and sensors for same.
One example of a tire assembly in accordance with the subject matter of the present disclosure can include a tire with a tire body that includes a cylindrical tread region and axially-spaced first and second sidewalls extending radially inward to respective first and second mounting beads that at least partially define a central opening of the tire body. The tire body can include an inner surface, and the cylindrical tread region can include an exterior tread adapted to roll along an associated road surface. The cylindrical tread region together with the first and second sidewalls can at least partially define an annular tire chamber with an open end in communication with the central opening of the tire body. A tire height and contact patch sensor can be at least partially disposed within the annular tire chamber. The sensor can include an electrical power source and a radar source communicatively coupled with the electrical power source. The radar source can be operable to emit millimeter wavelength radar waves into the annular tire chamber toward a target area along the inner surface of the tire body. A radar receptor can be communicatively coupled with the electrical power source and operable to receive millimeter wavelength radar waves reflected off of the target area along the inner surface of the tire body. The radar receptor can also be operable to generate a signal having a relation to the reflected radar waves and/or receipt of the reflected radar waves at the radar receptor, such as in relation to a time of arrival, for example. An antenna can be communicatively coupled with at least the radar receptor and operable to transmit data, signals and/or communications having the relation to the reflected radar waves and/or receipt of the reflected radar waves at the radar receptor to an associated system external to the annular tire chamber. A processor can be communicatively coupled with at least one of the radar source, the radar receptor and the antenna. The processor can be operable to determine a distance between the radar source and the target area based on at least one of: (i) a time of flight required for the radar waves to travel from the radar source to the target area and then to the radar receptor; (ii) a frequency phase shift between the radar waves transmitted by the radar source and the radar waves reflected from the target area and received by the radar receptor.
One example of a vehicle system in accordance with the subject matter of the present disclosure can include an electronic control system, and at least one tire assembly according the foregoing paragraph in operative communication with the electronic control system.
Turning now to the drawings, it is to be understood that the showings are for purposes of illustrating examples of the subject matter of the present disclosure and are not intended to be limiting. Additionally, it will be appreciated that the drawings are not to scale and that portions of certain features and/or elements may be exaggerated for purpose of clarity and ease of understanding.
System S also includes an electronic control system 110 with an electronic control unit (ECU) 112 in operative communication with one or more of sensor modules 100 through respective receiver modules 130. In the embodiment illustrated in
Receiver modules 130 include a receiver module transceiver 132 and an antenna 134 connected to transceiver 132 for bi-directional wireless data communication with (and optional power transmission to) a respectively associated sensor module 100 using wireless RF signals. In the embodiment shown in
In accordance with the subject matter of the present disclosure, each internal tire height and contact patch sensor 100 generates and outputs data, signals, information and/or other communications having a relation to the inflated height of the respective tire assembly with which it is operatively associated, and also optionally generates and outputs data, signals, information and/or other communications having a relation to the dimensions (e.g., size and shape) of a contact patch defined between the tread of tire assembly T and the roadway or other surface on which the tire assembly is supported for rolling thereon. Each tire inflation height and contact patch sensor 100 also can generate and output data, signals, information and/or other communications having a relation to the deflection of the sidewalls of a tire portion of tire assemblies T, a relation to an angle or change of angle between a target portion of the tire and sensor 100, and/or having a relation to the velocity and/or acceleration at which a portion of tire TR is moving relative to sensor S.
In a preferred arrangement, in accordance with the subject matter of the present disclosure, tire height and contact patch sensors 100 are located inside tire chamber C of tire assembly T and can be of a type, kind and/or construction that utilizes a radio wave (radar) transmitter operable to direct millimeter wavelength radar waves of a frequency greater than 120 gigahertz (GHz) and a wavelength of less than or equal to 2.5 millimeters (mm) toward a target surface inside tire chamber C. In one embodiment, sensor devices 100 transmit radar waves of a frequency in the range of 120 to 240 gigahertz (GHz), inclusively, corresponding to a wavelength in the range of 2.5 to 1.25 millimeters (mm), inclusively.
Sensing devices 100 further include a radar receptor that receives radar waves reflected off of the target surface and generates signals, data, information and/or communications that vary according the received reflected radar waves. Sensor devices 100 include a sensor processor 106 that utilizes the signals, data, information and/or communications generated by the radar receptor to derive a distance (sometimes referred to as “height” or “displacement”) between the radar source and the target surface which corresponds to a height or inflation height H of tire assembly T (or all of the same can be derived by each receiver processor 136).
Sensor processor 106 or receiver processor 136 optionally also derives the relative velocity and/or acceleration between the radar source and the target surface. Sensor processor 106 or receiver processor 136 also optionally derives an angle or change of angle between the radar source and the target surface. Processors 106 and/or 136 (or ECU 112) derive these and other operational data and information based upon at least one of: (i) the time of flight for a radar wave to travel from the radar source to the target and then to the radar receptor; (ii) a frequency shift (or “phase shift”) between the radar waves transmitted by the radar source and the radar waves reflected from the target surface and received by the radar receptor using a pulsed Doppler method or a continuous wave frequency modulation (CWFM) method; (iii) angle of arrival or change in angle of arrival of radar waves reflected from the target surface and received by the radar receptor. The distance derived by sensor processor 106 and/or receiver processor 136 has a relationship to the “inflation height” H (
Tire assembly T is shown in
Inflation height and contact patch sensor 100 can include a self-contained, rechargeable electrical power source 178 (e.g., one or more batteries) and can also include radio frequency (RF) antenna 104 suitable for wireless reception and/or transmission of signals, data and/or information for communication and/or other purposes. Antenna 104 (or, a second antenna can be included and) can be connected to an optional radio frequency energy harvesting circuit 182 (
During use, in accordance with the subject matter of the present disclosure, inflation height and contact patch sensors 100 are shown in
Sensor 100, or a system or component operatively associated with the sensor, can be operable to determine time of flight of the radar waves traveling at the speed of light (i.e., 299,792,458 meters per second (m/s) in air) from radar source 160, to target TG and then to radar receptor 170. It will be appreciated that the roundtrip distance traveled by the radar waves will have a relation to the time of flight. Thus, by determining the time of flight of the radar waves, a distance H′ between radar source 160 and target TG can be determined by processors 106 and/or 136 or by ECU 112 or another processor. When the target TG is provided as tread region inner surface TDi, this distance H′ between radar source 160 and radar receptor 170 is directly related to and varies directly with inflation height H of tire assembly T such that distance H′ (and inflation height H) decreases as air pressure in tire chamber C is reduced (until rim R contacts road surface RD) and distance H′ (and inflation height H) increases to a maximum value when tire TR is fully inflated (until sidewalls S1 and S2 are extended to a maximum height). As noted above, “inflation height” H of tire assembly T is defined as the minimum distance between rim R and roadway RD or other surface on which tire assembly T is operably supported. As such, sensor processor 106 and/or receiver processor 136 and/or ECU 112 and/or other processors can determine and/or assess changes in inflation height H based upon distance H′ measured by sensor 100 and/or changes in distance H′ measured by sensor 100.
Additionally, or in the alternative, inflation height and contact patch sensor 100, or a system or component operatively associated therewith, can be operable to determine a frequency shift or phase shift between radar waves EMT transmitted by radar source 160 and radar waves RFL reflected from target TG and received by radar receptor 170 using pulsed Doppler radar pulses or continuous wave frequency modulation (CWFM) of continuously transmitted radar waves. In either case, it will be appreciated that, based upon the Doppler effect, the frequency shift exhibited by the reflected radar waves RFL relative to transmitted radar waves EMT will have a relation to relative movement between source 160 and target TG. Thus, by determining the time of flight of the radar waves and/or by determining the phase shift of the radar waves, sensor 100, or a system or component operatively associated with sensor 100 (such as processor 106, processor 136, and/or ECU 112), can then determine distance H′ between source 160 and target TG and can also determine the velocity and acceleration of target TG relative to radar source 160. Sensor 100 can be operative to update such measurements rapidly to assess changes over time. Furthermore, sensor 100 can be operative to monitor and assess the angle of arrival or changes in the angle of arrival of reflected radar waves RFL as received by receptor 170. The angle of arrival or changes in the angle of arrival allow sensor processor 106 or receiver processor 136 to determine the angle or changes in the angle between tire inner surface ISF (e.g., as may be at least partially defined by TDi,S1i, and/or S2i) or another target TG and radar receptor 170. Accordingly, inflation height and contact patch sensors 100, or a system or component operatively associated therewith, are operable to determine a distance between, the angle between, velocity difference between, and/or acceleration between radar wave source 160 and target TG.
Additionally, or in the alternative, inflation height and contact patch sensors 100, or a system or component operatively associated therewith, can be operable to determine a distance between, the angle between, velocity difference between, and/or acceleration between radar source 160 and an alternative target located in tire chamber C such as any portion of one or both sidewalls S1 and S2 (e.g., such as sidewall inner surfaces S1i and/or S2i) and/or can be operable to determine a maximum distance defined between first and second sidewalls S1 and S2 across tire chamber C to assess inflation height H or pneumatic pressure contained in tire chamber C.
With reference also to
Sensors 100 include millimeter wave radar source 160 that is operable to emit radar waves through a transmit (TX) antenna 196 toward target surface, such as target TG or any other surface. In the illustrated example, radar source 160 includes a frequency modulated continuous wave transmitter 190 operably connected to a band pass filter 192 that passes signals of the frequency generated by transmitter 190 and a power amplifier 194 which, in turn, outputs emitted radar waves EMT through transmit antenna 196 toward target TG. Sensors 100 also includes a radar wave receptor 170 that is operable to sense, receive, or otherwise detect returned radar waves RFL reflected from the target through a receive (RX) antenna 200 and the angle of arrival of reflected radar waves RFL at receive (RX) antenna 200 which can include an array of multiple antennae. Receive antenna 200 is operably connected to a low noise amplifier 202 which outputs the amplified signal to a band pass filter 204.
An RF mixer 206 is operably connected to and receives input signals from band pass filter 204 and also the originally generated FMCW signal from frequency modulated continuous wave transmitter 190. Mixer 206 outputs a signal that represents the phase shift or phase difference between originally-transmitted radar FMCW signal EMT and received reflected signal RFL. RF mixer 206 is operably connected to and outputs the phase difference signal to an analog-to-digital converter (ADC) 208 which outputs the digital signal to a low pass filter 210 for conditioning the signal to remove undesired high-frequency noise. Low-pass filter 210 is operably connected to a Fast Fourier Transform (FFT) module 212 that performs a Fast Fourier Transform on the signal to obtain the desired frequency phase-shift data which are input to microprocessor 106 or another electronic controller, which can alternatively be receiver processor 136 of receiver module 130, ECU 112, and/or another microprocessor or other controller provided as part of system S and/or vehicle V. Processor 106 (or another electronic controller) derives height H′ and relative velocity and/or acceleration between transmit antenna 196 and target TG. Processors 106 and 136 and ECU 112 can be of any suitable type, kind and/or configuration, such as a microprocessor, for example, for processing data, executing software routines/programs, and other functions relating to at least the determination of the time of flight, frequency phase shift, and angle of arrival or changes in the angle of arrival for reflected radar waves RFL received by RX antenna 200. Additionally, sensors 100 can be communicatively coupled with other systems and/or components (e.g., controller 112 in
Additionally, processor 106 or other part of sensors 100 can include a non-transitory storage device or memory 220, which can be of any suitable type, kind and/or configuration that can be used to store data, values, settings, parameters, inputs, software, algorithms, routines, programs and/or other information or content for any associated use or function, such as used in association with the determination of the time of flight and frequency phase shift occurring between the transmitted radar waves and the reflected radar waves received via RX antenna 200 and/or for determining the angle of arrival of reflected radar waves RFL at RX antenna 200. Non-transitory memory 220 is operably communicatively coupled with processor 106 such that the processor can access the memory to retrieve and execute any one or more software programs and/or routines. Additionally, data, values, settings, parameters, inputs, software, algorithms, routines, programs, stored contact patch images for pattern matching, and/or other information or content can also be retained within memory 220 for retrieval by processor 106. It will be appreciated that such software routines can be individually executable routines or portions of a software program, such as an operating system, for example. Additionally, it will be appreciated that the controller, processing device and/or memory, can take any suitable form, configuration and/or arrangement, and that the embodiments shown and described herein are merely exemplary. Furthermore, it is to be understood, however, that the modules described above in detail can be implemented in any suitable manner, including, without limitation, software implementations, hardware implementations or any combination thereof.
Using such an arrangement, tire inflation height and contact patch sensors 100 can function as an extremely accurate sensor that is capable of providing signals, data and/or other information regarding tire inflation height H, velocity and acceleration of a target TG portion of tire body B relative to sensor 100, tire contact patch CP size & shape, and the angle or changes in the angle between target TG and sensor 100. This information can be used by other vehicle systems such as warning systems, ride control or handling systems, vibration control and active damping systems, and system that utilize road surface information such as active suspension systems or active engine mounts. Sensor 100 disclosed herein enable an accuracy of +/−1 millimeter increments to be achieved for distance/height measurements, with both measurements updated with new measurements at an update rate of less than 1 millisecond. In one embodiment, the displacement and velocity measurements are updated with new measurements every 700 microseconds.
It will be recognized that numerous different features and/or components are presented in the embodiments shown and described herein, and that no one embodiment may be specifically shown and described as including all such features and components. As such, it is to be understood that the subject matter of the present disclosure is intended to encompass any and all combinations of the different features and components that are shown and described herein, and, without limitation, that any suitable arrangement of features and components, in any combination, can be used. Thus, it is to be distinctly understood claims directed to any such combination of features and/or components, whether or not specifically embodied herein, are intended to find support in the present disclosure.
Thus, while the subject matter of the present disclosure has been described with reference to the foregoing embodiments and considerable emphasis has been placed herein on the structures and structural interrelationships between the component parts of the embodiments disclosed, it will be appreciated that other embodiments can be made and that many changes can be made in the embodiments illustrated and described without departing from the principles hereof. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the subject matter of the present disclosure and not as a limitation. As such, it is intended that the subject matter of the present disclosure be construed as including all such modifications and alterations.
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/042039 | 7/15/2020 | WO |
Number | Date | Country | |
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62874326 | Jul 2019 | US |