LIDAR Laser Health Diagnosis

Abstract

This invention relates to LIDAR laser health diagnostics. A sensor diagnostic system includes: a first sensor configured to receive a reflected signal corresponding to a portion of an emitted signal reflected from a surface from a second sensor; a wavelength determination module configured to determine a first wavelength of the reflected signal, the first wavelength indicating a second wavelength of the emitted signal; a wavelength shift detection module configured to determine a shift of at least one of the first and second wavelengths; and a sensor health analysis module configured to perform diagnostics on the second sensor based on the determined shift.

Description

Technical Field

[0001] introduction

[0002] The information provided in this section is for the purpose of generally presenting the contents of this disclosure. The work of the currently named inventors, to the extent described in this section, and in respect of aspects of that description that may not otherwise qualify as prior art at the time of filing, is neither expressly nor implicitly acknowledged as prior art to this disclosure.

[0003] This disclosure relates to vehicles, and more specifically to systems and methods for performing diagnostics on autonomous driving sensors.

[0004] The vehicle includes one or more torque-generating devices, such as an internal combustion engine and / or an electric motor. Passengers of the vehicle sit in the passenger compartment (or passenger car). Background Technology

[0005] Autonomous driving systems operate the vehicle completely independently of a human driver. For example, autonomous driving systems control the vehicle's acceleration, braking, and steering systems independently of the driver.

[0006] Semi-autonomous driving systems operate the vehicle partially independently of a human driver. For example, a semi-autonomous driving system can control the steering system independently of the driver, while relying on the driver to set the target speed for the semi-autonomous driving system by controlling the acceleration and braking systems. Summary of the Invention

[0007] A sensor diagnostic system includes: a first sensor configured to receive a reflected signal corresponding to a portion of a transmitted signal reflected from a surface from a second sensor; a wavelength determination module configured to determine a first wavelength of the reflected signal, the first wavelength indicating a second wavelength of the transmitted signal; a wavelength shift detection module configured to determine a shift of at least one of the first wavelength and the second wavelength; and a sensor health analysis module configured to perform diagnostics on the second sensor based on the determined shift.

[0008] Among other features, the second sensor is a light detection and ranging (LIDAR) sensor.

[0009] Among other features, the sensor health analysis module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on the determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in said at least one operating characteristic.

[0010] Among the other features, the at least one operational characteristic includes at least one of die temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

[0011] Among other features, the sensor health analysis module is configured to determine changes in at least one operating characteristic of the LIDAR sensor based on a lookup table that associates the determined shift with the change in the at least one operating characteristic.

[0012] Among other features, the sensor health analysis module is configured to perform diagnostics on the LIDAR sensor based on a comparison between changes in the at least one operating characteristic and a threshold.

[0013] Among other features, an autonomous module is configured to selectively control the vehicle's functions; and based on diagnostics, to perform functions such as stopping the vehicle, disabling the LIDAR sensor, and activating an indicator.

[0014] Among other features, the wavelength shift detection module is configured to determine the shift based on a comparison between at least one of a first wavelength and a second wavelength and a reference wavelength.

[0015] Among other features, at least one of the spectrometer and the spectroradiometer is configured to determine the first wavelength of the reflected signal.

[0016] Among other features, the sensor diagnostic system includes a liquid crystal metasurface.

[0017] Among other features, the first and second sensors are located in the passenger compartment of the vehicle.

[0018] Among other features, the first and second sensors are arranged within the same housing.

[0019] Among other features, the first and second sensors are located in the passenger compartment of the vehicle.

[0020] A sensor diagnostic system for a vehicle includes a Light Detection and Ranging (LIDAR) sensor, comprising a transmitting portion and a receiving portion. The transmitting portion is configured to transmit a signal, and the receiving portion is configured to receive a first portion of the transmitted signal reflected from an object in the environment outside the vehicle as a received signal. A reflected signal sensor is positioned to receive a reflected signal corresponding to a second portion of the transmitted signal reflected from a surface of the vehicle. A sensor diagnostic module is configured to determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal; determine a shift of at least one of the first and second wavelengths; and perform diagnostics on the LIDAR sensor based on the determined shift.

[0021] Among other features, the sensor diagnostic module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on the determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic.

[0022] Among the other features, the at least one operational characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

[0023] Among other features, the sensor diagnostic module is configured to perform diagnostics on the LIDAR sensor based on a comparison between changes in the at least one operating characteristic and a threshold.

[0024] Among other features, an autonomous module is configured to selectively control the vehicle's functions; and based on diagnostics, to perform functions such as stopping the vehicle, disabling the LIDAR sensor, and activating an indicator.

[0025] Among other features, the sensor diagnostic module is configured to determine the shift based on a comparison between at least one of a first wavelength and a second wavelength and a reference wavelength.

[0026] A method for diagnosing a vehicle's optical detection and ranging (LIDAR) sensor includes: transmitting a signal from the LIDAR sensor in the passenger compartment of the vehicle; receiving a first portion of the transmitted signal that passes through the vehicle's windshield and is reflected from an object in the environment outside the passenger compartment as a received signal; receiving a reflected signal using a reflected signal sensor disposed within the passenger compartment of the vehicle, the reflected signal corresponding to a second portion of the transmitted signal that is reflected from an interior surface within the passenger compartment and does not pass through the windshield; determining a first wavelength of the reflected signal that indicates a second wavelength of the transmitted signal; determining a shift of at least one of the first wavelength and the second wavelength; and performing diagnostics on the LIDAR sensor based on the determined shift.

[0027] This invention includes the following technical solutions:

[0028] Option 1. A sensor diagnostic system, comprising:

[0029] A first sensor is configured to receive a reflected signal, wherein the reflected signal corresponds to a portion of a transmitted signal emitted from a second sensor that is reflected from a surface.

[0030] A wavelength determination module is configured to determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal;

[0031] A wavelength shift detection module configured to determine a shift of at least one of the first wavelength and the second wavelength; and

[0032] A sensor health analysis module is configured to perform diagnostics on the second sensor based on the determined displacement.

[0033] Option 2. The sensor diagnostic system according to Option 1, wherein the second sensor is a light detection and ranging (LIDAR) sensor.

[0034] Option 3. The sensor diagnostic system according to Option 2, wherein the sensor health analysis module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic.

[0035] Option 4. The sensor diagnostic system according to Option 3, wherein the at least one operating characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

[0036] Option 5. The sensor diagnostic system according to Option 3, wherein the sensor health analysis module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a lookup table, the lookup table associating the determined shift with the change in the at least one operating characteristic.

[0037] Option 6. The sensor diagnostic system according to Option 3, wherein the sensor health analysis module is configured to perform a diagnosis of the LIDAR sensor based on a comparison between a change in the at least one operating characteristic and a threshold.

[0038] Option 7. The sensor diagnostic system according to Option 3 further includes an autonomous module configured to: (i) selectively control the functions of the vehicle; and (ii) based on the diagnostics, stop controlling the functions of the vehicle, disable the LIDAR sensor, and activate an indicator.

[0039] Option 8. The sensor diagnostic system according to Option 1, wherein the wavelength shift detection module is configured to determine the shift based on a comparison between (i) at least one of the first wavelength and the second wavelength and (ii) a reference wavelength.

[0040] Option 9. The sensor diagnostic system according to Option 1 further includes at least one of a spectrometer and a spectroradiometer, configured to determine a first wavelength of the reflected signal.

[0041] Option 10. The sensor diagnostic system according to Option 1 further includes a liquid crystal metasurface.

[0042] Option 11. The sensor diagnostic system according to Option 1, wherein the first sensor and the second sensor are arranged in the passenger compartment of the vehicle.

[0043] Option 12. The sensor diagnostic system according to Option 1, wherein the first sensor and the second sensor are arranged in the same housing.

[0044] Option 13. The sensor diagnostic system according to Option 1, wherein the first sensor and the second sensor are arranged in the passenger compartment of the vehicle.

[0045] Option 14. A sensor diagnostic system for a vehicle, the sensor diagnostic system comprising:

[0046] A light detection and ranging (LIDAR) sensor, wherein the LIDAR sensor includes a transmitting part and a receiving part, wherein the transmitting part is configured to transmit a signal, and wherein the receiving part is configured to receive a first portion of the transmitted signal reflected from an object in the environment outside the vehicle as a received signal;

[0047] A reflected signal sensor, positioned to receive a reflected signal corresponding to a second portion of the transmitted signal reflected from the surface of the vehicle; and

[0048] A sensor diagnostic module is configured to: (i) determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal; (ii) determine a shift of at least one of the first wavelength and the second wavelength; and (iii) perform diagnostics on the LIDAR sensor based on the determined shift.

[0049] Option 15. The sensor diagnostic system according to Option 14, wherein the sensor diagnostic module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic.

[0050] Option 16. The sensor diagnostic system according to Option 15, wherein the at least one operating characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

[0051] Option 17. The sensor diagnostic system according to Option 15, wherein the sensor diagnostic module is configured to perform diagnostics on the LIDAR sensor based on a comparison between a change in the at least one operating characteristic and a threshold.

[0052] Option 18. The sensor diagnostic system according to Option 15 further includes an autonomous module configured to: (i) selectively control the functions of the vehicle; and (ii) based on the diagnostics, stop controlling the functions of the vehicle, disable the LIDAR sensor, and activate an indicator.

[0053] Option 19. The sensor diagnostic system according to Option 14, wherein the sensor diagnostic module is configured to determine the shift based on a comparison between (i) at least one of the first wavelength and the second wavelength and (ii) a reference wavelength.

[0054] Option 20. A method for diagnosing a vehicle's optical detection and ranging (LIDAR) sensor, the method comprising:

[0055] Signals are emitted from the LIDAR sensor from the passenger compartment of the vehicle;

[0056] The first portion of the transmitted signal that passes through the windshield of the vehicle and is reflected from an object in the environment outside the passenger compartment is used as the received signal;

[0057] A reflected signal sensor disposed in the passenger compartment of the vehicle is used to receive a reflected signal, the reflected signal corresponding to a second portion of the transmitted signal that is reflected from the interior surface of the passenger compartment without passing through the windshield;

[0058] Determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal;

[0059] Determine the shift of at least one of the first wavelength and the second wavelength; and

[0060] Diagnostics are performed on the LIDAR sensor based on the determined displacement.

[0061] Further applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0062] This disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0063] Figure 1 This is a functional block diagram of an example vehicle system;

[0064] Figure 2 This is a functional block diagram of an example vehicle that includes external sensors and cameras;

[0065] Figure 3 This is a functional block diagram of an example sensor diagnostic system, including a sensor diagnostic module; and

[0066] Figure 4 The illustration shows the steps of an example method for performing diagnostics on a sensor.

[0067] In the accompanying drawings, reference numerals may be reused to identify similar and / or identical elements. Detailed Implementation

[0068] The vehicle may include one or more cameras and / or one or more sensors (i.e., combined transmitter / sensor) for autonomous driving. For example, the sensors may include one or more light detection and ranging (LIDAR) sensors. The systems and methods according to this disclosure are configured to perform diagnostics (e.g., health / functional assessments) on the sensors. In one example, a sensor diagnostic module detects a wavelength shift of laser light emitted and received by the sensor and diagnoses the sensor based on that wavelength shift. Various mechanisms may be implemented to measure or estimate the wavelength shift, including, but not limited to, spectrometers, spectroradiometers, metasurfaces arranged to receive / reflect laser light (e.g., liquid crystal (LC) metasurfaces), prisms, mirrors, and / or Bragg grating elements, etc. Although described with respect to vehicle implementations, the principles of this disclosure can also be applied to non-vehicle implementations or implemented within any laser (LASER) module.

[0069] Now for reference Figure 1 A functional block diagram of an example vehicle system 100 is presented. Although a vehicle system for a hybrid vehicle is shown and will be described, this disclosure is also applicable to non-hybrid vehicles, electric vehicles, fuel cell vehicles, and other types of vehicles.

[0070] Engine 102 combusts an air / fuel mixture to generate drive torque. Engine control module (ECM) 106 controls engine 102. For example, ECM 106 controls the actuation of engine actuators such as throttle valves, one or more spark plugs, one or more fuel injectors, valve actuators, camshaft phase shifters, exhaust gas recirculation (EGR) valves, one or more turbochargers, and other suitable engine actuators.

[0071] Engine 102 can output torque to transmission 110. Transmission control module (TCM) 114 controls the operation of transmission 110. For example, TCM 114 can control gear selection within transmission 110 and one or more torque transmission devices (e.g., torque converters, one or more clutches, etc.).

[0072] The vehicle system may include one or more electric motors. For example, electric motor 118 may be implemented within transmission 110, such as... Figure 1 As shown in the example, the electric motor can act as either a generator or a motor at a given time. When acting as a generator, the electric motor converts mechanical energy into electrical energy. The electrical energy can be used, for example, to charge the battery 126 via a power control device (PCD) 130. When acting as a motor, the electric motor generates torque that can, for example, supplement or replace the torque output by the engine 102. While an example of an electric motor is provided, a vehicle may include zero or more electric motors.

[0073] Power inverter module (PIM) 134 controls electric motor 118 and PCD 130. PCD 130 applies (e.g., DC) power from battery 126 to (e.g., AC) electric motor 118 based on signals from PIM 134, and PCD 130 provides power output by electric motor 118 to battery 126, for example. In various embodiments, PIM 134 may be referred to as inverter module.

[0074] Steering control module 140 controls the steering / turning of the vehicle's wheels, for example, based on driver turning of the steering wheel within the vehicle and / or steering commands from one or more vehicle control modules. A steering wheel angle sensor (SWA) monitors the rotational position of the steering wheel and generates SWA 142 based on the steering wheel's position. As an example, steering control module 140 may control vehicle steering via EPS motor 144 based on SWA 142. However, the vehicle may include another type of steering system.

[0075] The Electronic Brake Control Module (EBCM) 150 can selectively control the vehicle's brakes 154. Modules within the vehicle can share parameters via a Controller Area Network (CAN) 162. CAN 162 can also be referred to as an automotive local area network. For example, CAN 162 may include one or more data buses. Various parameters can be made available to other control modules via CAN 162 through a given control module.

[0076] Driver input may include, for example, an accelerator pedal position (APP) 166 that may be provided to ECM 106. Cruise control input 168 may also be input from a cruise control system to ECM 106. In various embodiments, the cruise control system may include an adaptive cruise control system. Brake pedal position (BPP) 170 may be provided to EBCM 150. Park, reverse, neutral, and drive lever (PRNDL) positions 174 may be provided to TCM 114. Ignition state 176 may be provided to Body Control Module (BCM) 178. For example, the ignition state 176 may be input by the driver via an ignition key, button, or switch. At a given time, ignition state 176 may be one of off, accessory, running, or cranking relay circuits.

[0077] The vehicle system may include an infotainment module 180, which controls what is displayed on a display 182. In various embodiments, the display 182 may be a touchscreen display, and signals indicating user input to the display 182 may be transmitted to the infotainment module 180. The infotainment module 180 may additionally or alternatively receive signals indicating user input from one or more other user input devices 184 (such as one or more switches, buttons, knobs, etc.).

[0078] The infotainment module 180 can receive signals from multiple external sensors and cameras (generally...) Figure 1 The input from external sensors and cameras 186 (illustrated in Figure 186) is used for input. For example, the infotainment module 180 can display video, various views, and / or alarms on the display 182 via input from external sensors and cameras 186. External sensors and cameras 186 may include sensors (e.g., LiDAR sensors) that capture images and videos outside the vehicle, as well as various types of sensors that measure parameters outside the vehicle. Input from external sensors and cameras 186 can be used to control autonomous driving.

[0079] For example, the autonomous module 188 may be configured to control the vehicle's steering, acceleration, deceleration, and braking during autonomous driving. For instance, the autonomous module 188 may detect features and objects around the vehicle based on input from external cameras and sensors 186, and control steering, acceleration, and deceleration based on these features and objects to avoid any detected objects. However, during autonomous driving, driver input (e.g., steering, braking, and / or acceleration input) may override input from the autonomous module 188. The autonomous module 188 (and / or another module, such as ECM 106) according to this disclosure implements a sensor diagnostic module as described in more detail below.

[0080] The infotainment module 180 may also generate output via one or more other devices. For example, the infotainment module 180 may output sound via one or more speakers 190 of the vehicle. The vehicle may include one or more additional control modules, such as a chassis control module, a battery pack control module, etc., not shown. One or more of the control modules shown and discussed may be omitted from the vehicle.

[0081] Global Positioning System (GPS) module 192 receives GPS data from a GPS system. Driver monitoring module 194 includes one or more means configured to monitor one or more characteristics of the driver of the vehicle. For example, driver monitoring module 194 may include one or more cameras configured to capture images of the driver and the passenger compartment of the vehicle, for example, to determine facial expressions, one or more gestures, hand placement, and other driver information based on these images.

[0082] The V2X module 196 communicates with other vehicles via a vehicle-to-vehicle (V2V) communication protocol and / or with infrastructure via a vehicle-to-infrastructure (V2I) communication protocol. V2V and V2I communications can be more broadly referred to as V2X communications.

[0083] Now for reference Figure 2 The diagram presents a functional block diagram of vehicle 200, which includes external sensors and cameras (e.g., such as...). Figure 1 Examples of external sensors and cameras 186 described herein. External sensors and cameras 186 include various cameras positioned to capture images and videos outside the vehicle 200 (outside the vehicle 200), and various types of sensors measuring parameters outside the vehicle 200 (outside the vehicle 200). For example, a forward-facing camera 204 captures images and videos within a predetermined field of view (FOV) 206 in front of the vehicle 200.

[0084] The front-facing camera 208 can also capture images and videos within a predetermined field of view (FOV) 210 in front of the vehicle 200. The front-facing camera 208 can capture images and videos within a predetermined distance in front of the vehicle 200 and may be located in front of the vehicle 200 (e.g., in the hood, grille, or bumper). The front-facing camera 204 may be located further rearward, such as in the case of a rearview mirror within the windshield of the vehicle 200. The front-facing camera 204 may not capture images and videos of objects within all or at least a portion of the predetermined FOV of the front-facing camera 208, and may capture images and videos beyond a predetermined distance in front of the vehicle 200. In various embodiments, only one of the front-facing camera 204 and the front-facing camera 208 may be included.

[0085] A rear-facing camera 212 captures images and videos within a predetermined field of view (FOV) 214 behind the vehicle 200. The rear-facing camera 212 can capture images and videos within a predetermined distance behind the vehicle 200 and can be located at the rear of the vehicle 200, such as near the rear license plate. A right-facing camera 216 captures images and videos within a predetermined FOV 218 on the right side of the vehicle 200. The right-facing camera 216 can capture images and videos within a predetermined distance on the right side of the vehicle 200 and can be located, for example, below the right-facing rearview mirror. In various embodiments, the right-facing rearview mirror may be omitted, and the right-facing camera 216 may be located near the position where the right-facing rearview mirror would normally be. A left-facing camera 220 captures images and videos within a predetermined FOV 222 on the left side of the vehicle 200. The left-facing camera 220 can capture images and videos within a predetermined distance on the left side of the vehicle 200 and can be located, for example, below the left-facing rearview mirror. In various embodiments, the left-facing rearview mirror may be omitted, and the left-facing camera 220 may be located near the position where the left-facing rearview mirror would normally be. Although an example FOV is shown for illustrative purposes, FOVs may overlap, for example, for more accurate and / or inclusive stitching.

[0086] External sensors and cameras 186 also include various other types of sensors, such as radar sensors, one or more LiDAR sensors 250, etc. For example, vehicle 200 may include one or more forward-facing radar sensors (such as forward-facing radar sensors 226 and 230) and one or more rearward-facing radar sensors (such as rearward-facing radar sensors 234 and 238). Vehicle 200 may also include one or more right-side radar sensors (such as right-side radar sensor 242) and one or more left-side radar sensors (such as left-side radar sensor 246). The positions and fields of view of the cameras and radar sensors are provided as examples only, and different positions and fields of view can be used. The radar sensors output radar signals around vehicle 200. Objects around vehicle 200 can be detected based on input from external sensors and cameras 186.

[0087] One or more sensors may be located behind the windshield (e.g., inside the passenger compartment of vehicle 200, such as a forward-facing camera 204 as described above). In some examples, a LIDAR sensor, including a LIDAR transmitter and a sensor, is located inside the passenger compartment. Therefore, a signal emitted from the LIDAR sensor passes through the windshield, is reflected by objects in the environment outside the vehicle, and returns through the windshield to be received by the LIDAR sensor. A portion of the emitted signal is reflected back into the passenger compartment from the inner surface of the windshield. The sensor diagnostic module according to this disclosure is configured to perform diagnostics on the transmitter of the LIDAR sensor based on the reflected signal, as described in more detail below.

[0088] Now for reference Figure 3 The example sensor diagnostic system 300 according to this disclosure includes a sensor diagnostic module 304. The sensor diagnostic module 304 is configured to perform diagnostics on a sensor (e.g., a LiDAR sensor) 308. The sensor 308 is configured to emit a signal (e.g., a laser signal) 312 from within the interior of a vehicle (e.g., vehicle 200) through the windshield 316 of vehicle 200. For example, the sensor 308 is disposed in the passenger compartment of vehicle 200, such as on the ceiling of the passenger compartment, on or near a rearview mirror, on a dashboard, etc.

[0089] Signal 312 passes through windshield 316 and is reflected by object 320 in the environment surrounding vehicle 200 and received by sensor 308 as received signal 324. Autonomous module 328 can detect features and objects in the environment surrounding vehicle 200 based on input from sensor 308. For example, received signal 324 indicates the distance between vehicle 200 and object 320, and autonomous module 328 accordingly controls the functions of vehicle 200, as described in more detail above.

[0090] A portion of signal 312 is reflected back into the interior of vehicle 200 by the inner surface of windshield 316 (as reflected signal 332). One or more reflected signal sensors or receivers 336 are positioned to receive reflected signal 332. For example, reflected signal sensor 336 is arranged in the passenger compartment of vehicle 200 at a location corresponding to a known or predetermined trajectory of reflected signal 332, such as on the ceiling of the passenger compartment, on or near a rearview mirror, on the dashboard, etc. In some examples, reflected signal sensor 336 is positioned adjacent to sensor 308 or integrated within sensor 308 (e.g., integrated into the same housing as sensor 308). The trajectory of reflected signal 332 may depend on the rake or angle of windshield 316, the material composition of windshield 315, etc. Therefore, the trajectory of reflected signal 332 and the position of reflected signal sensor 336 may vary depending on the vehicle. In some examples, the windshield 316 may include an embedded or attached reflective module (not shown) that is positioned to receive and reflect signal 312 along a predetermined trajectory (i.e., toward the desired position of reflective signal sensor 336).

[0091] In some examples, the liquid crystal metasurface may be arranged to receive signal 312 or reflect signal 332. For example, the liquid crystal metasurface may be arranged adjacent to or embedded within the windshield 316, and may be configured to receive signal 312 and direct one or more of the reflected signals 332 in a desired direction. In other examples, the reflected signal sensor 336 may include a liquid crystal metasurface configured to receive reflected signal 332. In still other examples, the liquid crystal metasurface may be arranged elsewhere in the passenger compartment, within sensor 308, etc.

[0092] Sensor diagnostic module 304 is configured to perform diagnostics on sensor 308 (e.g., the transmitter portion of sensor 308) based on reflected signal 332. For example, sensor diagnostic module 304 receives the output 340 of reflected signal sensor 336, which indicates the characteristics of reflected signal 332. Sensor diagnostic module 304 is configured to determine the wavelength of reflected signal 332, which indicates the wavelength of signal 312 emitted from sensor 308. Sensor diagnostic module 304 determines (diagnoses) the condition of sensor 308 based on the determined wavelength of reflected signal 332.

[0093] For example, sensor diagnostic module 304 includes wavelength determination module 344, which is configured to determine the wavelength of reflected signal 332 based on the output 340 of reflected signal sensor 336 and correspondingly determine the wavelength of signal 312. For example, reflected signal sensor 336 and wavelength determination module 344 may correspond to components of a chip-scale spectrometer configured to receive reflected signal 332, measure the wavelength of reflected signal 332, and output a wavelength signal 348 indicating the measured wavelength. In another example, reflected signal sensor 336 and / or wavelength determination module 344 may include components, including but not limited to prisms, Bragg deflectors or grating elements, beam combiners, fiber optic cables, and couplers, configured to receive reflected signal 332, measure the wavelength of reflected signal 332, and output wavelength signal 348.

[0094] In one example, wavelength signal 348 may correspond to the wavelength of reflected signal 332. In another example, wavelength determination module 344 determines the wavelength of signal 312 based on the measured wavelength of reflected signal 332, and wavelength signal 348 corresponds to the wavelength of signal 312.

[0095] Wavelength shift detection module 352 receives wavelength signal 348 and calculates wavelength shift based on changes in wavelength signal 348. For example, wavelength shift detection module 352 is configured to compare wavelength signal 348 with a reference wavelength. During normal operation, the reference wavelength may correspond to the wavelength of transmitted signal 312. The reference wavelength may be determined during manufacturing, measured during calibration of sensor 308, or determined over time during the operation of sensor 308, etc. Wavelength shift detection module 352 outputs wavelength shift signal 356 indicating the calculated wavelength shift.

[0096] The sensor health analysis module 360 ​​receives the wavelength shift signal 356 and is configured to perform diagnostics on the sensor 308 based on the wavelength shift signal 356. The wavelength of the signal 312 (and correspondingly, the wavelength shift indicated by the wavelength shift signal 356) indicates various operating characteristics of the sensor 308, which can further indicate the health status of the sensor 308.

[0097] For example, the wavelength of signal 312 can indicate the operating characteristics of sensor 308, including but not limited to chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power, and beam intensity of sensor 308, as well as amplitude shift, phase shift, and / or polarization shift. In other words, wavelength shift indicates a corresponding change in the operating characteristics of sensor 308. The relationship between wavelength shift and changes in the operating characteristics of sensor 308 can vary depending on the laser type and other operating or environmental characteristics (e.g., temperature). For example, chip temperature can have a generally linear or piecewise linear relationship with the wavelength of signal 312. By way of example only, sensor health analysis module 360 ​​can use a lookup table (which associates wavelength shift with corresponding changes in operating characteristics), formulas or algorithms that use wavelength shift as input to calculate the corresponding operating characteristics, models, etc., to determine changes in the operating characteristics of sensor 308.

[0098] The sensor health analysis module 360 ​​is configured to selectively command and / or execute one or more corrective actions based on corresponding changes in wavelength shift and operating characteristics. For example, the sensor health analysis module 360 ​​outputs a diagnostic result signal 364 requesting one or more corrective actions. By way of example only, the diagnostic result signal 364 may indicate that a change in one or more of the wavelength shift and / or the operating characteristics of the sensor 308 exceeds a corresponding threshold.

[0099] In some examples, the sensor health analysis module 360 ​​may be configured to predict the degradation and / or remaining lifetime of the sensor 308. For example, as wavelength shift changes or increases over time, the sensor health analysis module 360 ​​may predict (e.g., based on the rate of change of wavelength) when the wavelength shift will reach a threshold indicating that the sensor 308 is no longer reliable.

[0100] The autonomous module 328 can receive diagnostic result signal 364 and selectively perform corrective actions based on the diagnostic result signal 364. Corrective actions include, but are not limited to, activating indicators to notify the driver of the health status of sensor 308 (e.g., starting check engine or other diagnostic lights, displaying information on the display screen, etc.), deactivating sensor 308, ignoring input received from sensor 308, disabling autonomous driving functions, etc.

[0101] Figure 4 This is an example method 400 for performing diagnostics on sensor 308 according to the principles of this disclosure. At 404, method 400 emits a signal from the sensor (e.g., a laser emitted from a LIDAR sensor, such as signal 312 emitted from sensor 308). At 408, method 400 (e.g., a reflective signal sensor 336) receives a portion of the signal reflected from a surface (such as the inner surface of windshield 316). At 412, method 400 (e.g., a corresponding component of reflective signal sensor 336 and / or wavelength determination module 344) determines and outputs the wavelength of the reflected signal and / or the wavelength of the emitted signal.

[0102] At 416, method 400 (e.g., wavelength shift detection module 352) determines and outputs the wavelength shift of the reflected signal and / or the emitted signal. At 420, method 400 (e.g., sensor health analysis module 360) performs diagnostics on sensor 308 based on the wavelength shift. For example, sensor health analysis module 360 ​​determines changes in the operating characteristics of sensor 308 based on the wavelength shift and performs diagnostics based on these changes.

[0103] At 424, method 400 (e.g., sensor health analysis module 260, autonomous module 328, etc.) determines, based on diagnostics, whether to perform one or more corrective actions. For example, method 400 determines whether one or more of wavelength shift and operating characteristics exceed a corresponding threshold indicating performance degradation (e.g., inaccurate sensing results). If true, method 400 proceeds to 428. If false, method 400 proceeds to 404.

[0104] At 428, method 400 (e.g., sensor health analysis module 260, autonomous module 328, etc.) selectively performs one or more corrective actions based on the diagnosis. Method 400 then continues to 404. Thus, method 400 can continuously (or in some examples, periodically, conditionally, etc.) monitor the reflected signal 332 to diagnose the health status of sensor 308.

[0105] The foregoing description is merely illustrative in nature and is not intended in any way to limit this disclosure, its application, or use. The broad teachings of this disclosure can be implemented in various forms. Therefore, although this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon studying the drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each of the embodiments described above is described as having certain features, any one or more of those features described with respect to any embodiment of this disclosure can be implemented in any other embodiment and / or combined with features from any other embodiment, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and permutations and combinations of one or more embodiments with each other remain within the scope of this disclosure.

[0106] Spatial and functional relationships between components (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connection,” “joint,” “link,” “proximity,” “adjacent,” “on top of,” “above,” “below,” and “set.” Unless explicitly described as “direct,” when describing the relationship between the first and second components in the above disclosure, the relationship can be a direct relationship in which no other intermediary components exist between the first and second components, or an indirect relationship in which one or more intermediary components exist between the first and second components (either spatially or functionally). As used herein, the phrases A, B, and C at least one should be interpreted as referring to the logic (A OR B OR C) using non-exclusive logic OR, and should not be interpreted as referring to “at least one of A, at least one of B, and at least one of C.”

[0107] In the accompanying drawings, the direction of the arrows generally illustrates the flow of information of interest to the illustration, such as data or instructions. For example, when components A and B exchange various information, but the information transmitted from component A to component B is relevant to the illustration, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for or confirmation of receipt of the information to component A.

[0108] In this application (including the following limitations), the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, be part of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuitry (shared, dedicated, or grouped) that executes code; memory circuitry (shared, dedicated, or grouped) that stores code executed by the processor circuitry; other suitable hardware components that provide the described functionality; or combinations of some or all of the above, such as in a system-on-a-chip.

[0109] A module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module disclosed herein may be distributed among multiple modules connected via the interface circuits. For example, multiple modules may allow for load balancing. In another example, a server (also referred to as a remote or cloud) module may perform some functions on behalf of a client module.

[0110] The term "code" as used above can include software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuitry" covers a single processor circuitry that executes some or all of the code from multiple modules. The term "grouped processor circuitry" covers processor circuitry that, in conjunction with additional processor circuitry, executes some or all of the code from one or more modules. The reference to multiple processor circuitry covers multiple processor circuitry on a discrete chip, multiple processor circuitry on a single chip, multiple cores of a single processor circuitry, multiple threads of a single processor circuitry, or a combination thereof. The term "shared memory circuitry" covers a single memory circuitry that stores some or all of the code from multiple modules. The term "grouped memory circuitry" covers memory circuitry that, in conjunction with additional memory, stores some or all of the code from one or more modules.

[0111] The term memory circuit is a subset of the term computer-readable medium. As used herein, the term computer-readable medium does not cover transient electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); therefore, the term computer-readable medium can be considered tangible and non-transitory. Non-limiting examples of non-transitory, tangible computer-readable media are non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape or hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0112] The apparatus and methods described in this application can be implemented, in part or in whole, by a special-purpose computer formed by a general-purpose computing mechanism that performs one or more specific functions implemented in a computer program. The function blocks, flowchart components, and other elements described above serve as software specifications that can be converted into computer programs through the routine work of a skilled technician or programmer.

[0113] A computer program includes processor-executable instructions stored on at least one non-transitory, tangible, computer-readable medium. A computer program may also include or depend on stored data. A computer program may encompass a basic input / output system (BIOS) that interacts with the hardware of a special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0114] Computer programs may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated from source code by a compiler; (iv) source code executed by an interpreter; (v) source code compiled and executed by a just-in-time compiler; and so on. As an example only, source code may be written using syntax from languages ​​including: C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, JavaScript®, HTML5 (Hypertext Markup Language version 5), Ada, ASP (Dynamic Server Web Pages), PHP (PHP: Hypertext Preprocessing Language), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®.

Claims

1. A sensor diagnostic system, comprising: A first sensor is configured to receive a reflected signal, wherein the reflected signal corresponds to a portion of a transmitted signal emitted from a second sensor that is reflected from a surface. A wavelength determination module is configured to determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal; A wavelength shift detection module configured to determine a shift of at least one of the first wavelength and the second wavelength; and A sensor health analysis module is configured to perform diagnostics on the second sensor based on the determined displacement; The second sensor is a light detection and ranging (LIDAR) sensor. The sensor health analysis module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic; and The at least one operating characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

2. The sensor diagnostic system according to claim 1, wherein, The sensor health analysis module is configured to determine changes in at least one operating characteristic of the LIDAR sensor based on a lookup table, which associates the determined shift with the change in the at least one operating characteristic.

3. The sensor diagnostic system according to claim 1, wherein, The sensor health analysis module is configured to perform diagnostics on the LIDAR sensor based on a comparison between changes in the at least one operating characteristic and a threshold.

4. The sensor diagnostic system of claim 1, further comprising an autonomous module configured to: (i) selectively control the functions of the vehicle; and (ii) based on the diagnostics, stop controlling the functions of the vehicle, disable the LIDAR sensor, and activate an indicator.

5. The sensor diagnostic system according to claim 1, wherein, The wavelength shift detection module is configured to determine the shift based on a comparison between (i) at least one of the first wavelength and the second wavelength and (ii) a reference wavelength.

6. The sensor diagnostic system of claim 1, further comprising at least one of a spectrometer and a spectroradiometer, configured to determine a first wavelength of the reflected signal.

7. The sensor diagnostic system according to claim 1, further comprising a liquid crystal metasurface.

8. The sensor diagnostic system according to claim 1, wherein, The first sensor and the second sensor are arranged in the passenger compartment of the vehicle.

9. The sensor diagnostic system according to claim 1, wherein, The first sensor and the second sensor are arranged in the same housing.

10. The sensor diagnostic system according to claim 1, wherein, The first sensor and the second sensor are arranged in the passenger compartment of the vehicle.

11. A sensor diagnostic system for a vehicle, the sensor diagnostic system comprising: A light detection and ranging (LIDAR) sensor, wherein the LIDAR sensor includes a transmitting part and a receiving part, wherein the transmitting part is configured to transmit a signal, and wherein the receiving part is configured to receive a first portion of the transmitted signal reflected from an object in the environment outside the vehicle as a received signal; A reflected signal sensor, positioned to receive a reflected signal corresponding to a second portion of the transmitted signal reflected from the surface of the vehicle; and A sensor diagnostic module is configured to: (i) determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal; (ii) determine a shift of at least one of the first wavelength and the second wavelength; and (iii) perform diagnostics on the LIDAR sensor based on the determined shift. The sensor diagnostic module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic. The at least one operating characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

12. The sensor diagnostic system according to claim 11, wherein, The sensor diagnostic module is configured to perform diagnostics on the LIDAR sensor based on a comparison between changes in the at least one operating characteristic and a threshold.

13. The sensor diagnostic system of claim 11, further comprising an autonomous module configured to: (i) selectively control the functions of the vehicle; and (ii) based on diagnostics, stop controlling the functions of the vehicle, disable the LIDAR sensor, and activate an indicator.

14. The sensor diagnostic system according to claim 11, wherein, The sensor diagnostic module is configured to determine the shift based on a comparison between (i) at least one of the first wavelength and the second wavelength and (ii) a reference wavelength.

15. A method for diagnosing a vehicle's light detection and ranging (LIDAR) sensor, the method comprising: Signals are emitted from the LIDAR sensor from the passenger compartment of the vehicle; The first portion of the transmitted signal that passes through the windshield of the vehicle and is reflected from an object in the environment outside the passenger compartment is used as the received signal; A reflected signal sensor disposed in the passenger compartment of the vehicle is used to receive a reflected signal, the reflected signal corresponding to a second portion of the transmitted signal that is reflected from the interior surface of the passenger compartment without passing through the windshield; Determine a first wavelength of the reflected signal, wherein the first wavelength indicates a second wavelength of the transmitted signal; Determine the shift of at least one of the first wavelength and the second wavelength; and Diagnostics are performed on the LIDAR sensor based on the determined shift; The sensor diagnostic module is configured to determine a change in at least one operating characteristic of the LIDAR sensor based on a determined displacement, and to perform diagnostics on the LIDAR sensor based on the determined change in the at least one operating characteristic. The at least one operating characteristic includes at least one of chip temperature, mode hopping, optical cavity stability, photon energy, pulse width, power and beam intensity, amplitude shift, phase shift, and polarization shift.

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