A steering wheel hands-off alarm trigger test system applied to a complex electromagnetic environment and a test method thereof

Abstract

The application relates to a steering wheel hand-off alarm trigger test system applied to a complex electromagnetic environment and a test method thereof, and the system comprises a compressed air tank, an electromagnetic valve, an upper computer, an air pipe, a pneumatic control device, a steering wheel clamp and a camera. The compressed air tank is used for storing compressed air. The electromagnetic valve is connected with the upper computer and is used for receiving instructions sent by the upper computer, so as to control the on-off, flow size and direction of the compressed air in the air pipe. One end of the pneumatic control device is connected with the electromagnetic valve through the air pipe, and the other end is connected with the steering wheel clamp through the air pipe, and the pneumatic control device is used for simulating the test action of a human hand on the steering wheel through the steering wheel clamp. The steering wheel clamp is installed in a vehicle to be tested in a wave darkroom. The camera is used for monitoring the relative position and action state of the steering wheel clamp and the steering wheel in real time. Compared with the prior art, the steering wheel hand-off alarm trigger test system significantly improves the action accuracy, stability and multi-scene applicability of the steering wheel hand-off alarm trigger test system in the complex electromagnetic environment.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic compatibility testing technology, and in particular to a steering wheel hands-off alarm triggering test system and test method for use in complex electromagnetic environments. Background Technology

[0002] With the widespread adoption of advanced driver assistance systems (ADAS), ensuring that drivers can take over the vehicle promptly when requested by the system has become a critical safety requirement. However, in actual driving, it is not uncommon for drivers to take their hands off the steering wheel (i.e., "hands off the steering wheel"). Such prolonged system-managed behavior introduces significant uncertainties and risks. Once these potential risks materialize, they will directly threaten road traffic safety.

[0003] Currently, mainstream hands-off detection technologies (such as capacitance and torque-based sensing solutions) can work effectively in controlled laboratory environments. However, in complex real-world electromagnetic environments (such as interference from high-power vehicle loads and communication modules), the signal-to-noise ratio of their sensing signals deteriorates drastically, leading to severe deficiencies in system reliability, stability, and anti-interference capabilities (i.e., robustness), resulting in false alarms or missed alarms. For example, patent application CN113247078A discloses a method and system for steering wheel hands-off detection. This method calculates a standard hand-grip threshold under default conditions, updates the current hand-grip threshold using a preset assignment function based on the steering wheel heating state, heating duration, and initial temperature, and then compares the steering wheel hand-grip value detected by the capacitance sensor with the threshold to determine the hands-off state. It also incorporates optimizations such as reducing the electric drive signal and adjusting the vehicle speed threshold for heating scenarios. However, this method can only handle predictable electric heating interference and cannot withstand sudden noise in real complex electromagnetic environments (such as high-power loads and communication module interference), nor can it meet the stable verification requirements of stringent electromagnetic compatibility testing equipment.

[0004] The severity of this problem is particularly evident in electromagnetic compatibility (EMC) testing. Since testing aims to accurately assess the performance of equipment under electromagnetic interference, the tooling design must maintain stable operation even under strong interference and must not become a new source of interference. Traditional testing methods or electromechanical structures often struggle to simultaneously meet these two stringent requirements, making the accurate reproduction and verification of the "steering wheel hands-off detection under complex electromagnetic conditions" scenario in a laboratory environment a long-standing challenge and pain point for the industry. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a steering wheel hands-off alarm triggering test system and its test method for use in complex electromagnetic environments, which significantly improves the action accuracy, stability and multi-scenario applicability of the steering wheel hands-off alarm triggering test system in complex electromagnetic environments.

[0006] The objective of this invention can be achieved through the following technical solutions: A steering wheel hands-off alarm triggering test system for use in complex electromagnetic environments includes: a compressed air tank, a solenoid valve, a host computer, an air pipe, a pneumatic control device, a steering wheel clamp, and a camera. The compressed air tank stores compressed air. The solenoid valve is connected to the host computer and receives commands from the host computer to control the flow, flow rate, and direction of compressed air in the air pipe. One end of the pneumatic control device is connected to the solenoid valve via the air pipe, and the other end is connected to the steering wheel clamp via the air pipe, simulating human hand movement on the steering wheel through the steering wheel clamp. In the test procedure, the pneumatic control device has a built-in air pressure detection unit connected to a host computer. This unit collects air pressure data from the pneumatic control device in real time and feeds it back to the host computer. The host computer then dynamically adjusts the flow rate of the solenoid valve based on the target grip force, forming a closed-loop control of the air pressure in the air duct. The steering wheel clamp is installed in the vehicle under test in an anechoic chamber. The camera is connected to the host computer to monitor the relative position and movement status of the steering wheel clamp and the steering wheel in real time, and feeds back the collected video signals to the host computer, forming a visual closed-loop feedback.

[0007] Furthermore, the test actions of simulating human hand movements on the steering wheel using the steering wheel clamp include removing the steering wheel and gripping it with different force.

[0008] Furthermore, the steering wheel clamp is made of non-metallic materials and includes two types: suction cup clamp and base clamp. The suction cup clamp is suitable for test scenarios where installation is quick through vehicle window glass, while the base clamp is suitable for test scenarios where the interior space of the vehicle allows or requires permanent fixation.

[0009] Furthermore, the suction cup clamp includes a suction cup, a multi-link robotic arm, and a steering wheel clamping mechanism, with the suction cup firmly adhering to the surface of the vehicle window glass.

[0010] Furthermore, the base-type clamp includes a base, a multi-link robotic arm, and a steering wheel clamping mechanism, wherein the base is fixed to a vehicle seat rail or a specific position on the chassis inside the vehicle.

[0011] Furthermore, the multi-link robotic arm is composed of multiple jointed robotic arms made of high-strength engineering plastic. Each jointed robotic arm is connected to a pneumatic telescopic cylinder via plastic screws. The extension and retraction of the pneumatic telescopic cylinder is controlled by a pneumatic control device, thereby enabling each jointed robotic arm to rotate around its connection point with other jointed robotic arms, so as to adjust the deployment angle and spatial posture of the multi-link robotic arm.

[0012] Furthermore, the steering wheel clamping mechanism consists of a first clamping mechanical arm and a second clamping mechanical arm. The first clamping mechanical arm and the second clamping mechanical arm are connected to a pneumatic telescopic cylinder by plastic screws. The extension and retraction of the pneumatic telescopic cylinder are controlled by a pneumatic control device, thereby causing the first clamping mechanical arm and the second clamping mechanical arm to move away from or closer to each other, so as to realize the removal of the steering wheel and the gripping of different strengths.

[0013] Furthermore, the contact ends of the first and second gripping robotic arms with the steering wheel are detachable to accommodate steering wheels of different sizes.

[0014] According to another aspect of the present invention, a test method for a steering wheel hands-off alarm triggering test system applied to a complex electromagnetic environment is provided. The method involves testing the steering wheel hands-off alarm triggering system of the vehicle under test using the steering wheel hands-off alarm triggering test system described above, and includes the following steps: Based on the interior space of the vehicle under test, a suitable steering wheel clamp is selected, and the vehicle under test is placed in an anechoic chamber; Adjust the steering wheel clamps to align them with the target grip area of ​​the steering wheel; The host computer sets the force, action sequence and duration of the simulated human hand grip, and controls the steering wheel clamp to perform one calibration cycle. The clamping position accuracy is confirmed by the video signal fed back by the camera, and the pressure mapping relationship is calibrated by the air pressure detection unit built into the pneumatic control device. According to the preset electromagnetic compatibility test standards, complex electromagnetic interference with specific frequency and field strength is applied to the steering wheel area through an electromagnetic interference source in an anechoic chamber. The host computer controls the pneumatic control device to drive the steering wheel clamp to perform release and clamping actions according to the preset test cases, simulating the human hand leaving the steering wheel and gripping it with different strengths, and monitors the triggering status of the hand-off alarm signal in real time through the vehicle's CAN bus. The host computer synchronously records the timestamps, command pressure, feedback air pressure, video confirmation frames, off-hand alarm signals, and environmental field strength data during the test process, and automatically calculates the false alarm rate, missed alarm rate, and alarm delay time to generate a test report. The host computer controls the steering wheel clamp to return to a safe position, shuts off the solenoid valve and electromagnetic interference source, and ends the test.

[0015] Furthermore, the types of sensors tested in the vehicle under test include capacitive sensors, pressure sensors, and torque sensors. When testing the capacitive sensors, metal foil or special electrode sheets that mimic the capacitance characteristics of a human hand are attached to the contact ends of the first and second gripping robotic arms. When testing the pressure and torque sensors, the first and second gripping robotic arms are used directly for clamping to simulate hand mechanical input.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention constructs a steering wheel off-hand alarm triggering test system consisting of a compressed air tank, a solenoid valve, a host computer, air pipes, a pneumatic control device, a steering wheel clamp, and a camera. The pneumatic control device drives the steering wheel clamp to simulate the removal of a human hand from the steering wheel and different grip strengths. The pneumatic control device's built-in air pressure detection unit collects real-time air pressure data, allowing the host computer to dynamically adjust the solenoid valve's flow rate based on the target grip strength, forming a closed-loop control of the air pressure in the air pipe. The camera monitors the relative position and movement status of the steering wheel clamp and the steering wheel in real time, feeding the collected video signals back to the host computer, forming a visual closed-loop feedback. This integrated pressure and visual dual closed-loop control architecture solves the problem of unreliable motion accuracy in existing technologies, significantly improving the motion accuracy of the test system in complex electromagnetic environments.

[0017] 2. This invention uses a steering wheel clamp made entirely of non-metallic materials to create a multi-link robotic arm, a steering wheel clamping mechanism, and connecting components. It combines suction cup clamps and base clamps to adapt to different installation requirements in various testing scenarios. This solves the problems of electromagnetic interference and poor scenario adaptability of metal structures in the prior art, and significantly improves the stability and multi-scenario applicability of the testing system in strong electromagnetic environments.

[0018] 3. This invention utilizes a pre-constructed steering wheel hands-off alarm trigger test to reproduce a complex electromagnetic environment in an anechoic chamber to test the hands-off alarm system of the vehicle under test. Simultaneously, it collects multi-dimensional data, automatically analyzes it, and generates reports. This solves the shortcomings of traditional testing methods, such as the inability to accurately reproduce complex electromagnetic scenarios, lack of differentiated adaptation for different sensor types, lack of standardized calibration procedures, incomplete coverage of test conditions, and reliance on manual data recording and analysis with limited dimensions. It achieves accurate verification of the hands-off detection system under all operating conditions, significantly improving the comprehensiveness, standardization, and automation of the test. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a steering wheel hands-off alarm triggering test system proposed in this invention and applied to complex electromagnetic environments; Figure 2 This is a schematic diagram of the suction cup clamp. Figure 3 This is a schematic diagram of the base-type clamp. Figure 4 This is a schematic diagram of a multi-link robotic arm. Figure 5 This is a schematic diagram of the steering wheel clamping mechanism; Figure 6This is a flowchart illustrating a test method for a steering wheel hands-off alarm triggering test system applied in complex electromagnetic environments, as proposed in this invention.

[0020] Legend: 1. Compressed air tank; 2. Solenoid valve; 3. Host computer; 4. Air pipe; 5. Pneumatic control device; 6. Steering wheel clamp; 61. Suction cup clamp; 611. Suction cup; 62. Base clamp; 621. Base; 7. Camera; 8. Steering wheel; 9. Multi-link robotic arm; 91. Articulated robotic arm; 10. Steering wheel clamping mechanism; 101. First clamping robotic arm; 102. Second clamping robotic arm; 11. Plastic screw; 12. Pneumatic telescopic cylinder. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0022] Example 1 This embodiment provides a steering wheel hands-off alarm triggering test system applicable to complex electromagnetic environments, such as... Figure 1 As shown, it includes: compressed air tank 1, solenoid valve 2, host computer 3, air pipe 4, pneumatic control device 5, steering wheel clamp 6, and camera 7.

[0023] Compressed air tank 1 is used to store compressed air, providing stable and clean compressed air, and is the pneumatic source of the entire testing system.

[0024] Solenoid valve 2 is connected to host computer 3 and is used to receive instructions from host computer 3, thereby controlling the flow, speed and direction of compressed air in air pipe 4.

[0025] One end of the pneumatic control device 5 is connected to the solenoid valve 2 via an air pipe 4, and the other end is connected to the steering wheel clamp 6 via an air pipe 4. The steering wheel clamp 6 is used to simulate the test actions of a human hand on the steering wheel 8. These simulated actions include removing the steering wheel 8 and gripping it with varying degrees of force. The pneumatic control device 5 has a built-in air pressure detection unit connected to a host computer 3. This unit collects real-time air pressure data from the pneumatic control device 5 and feeds it back to the host computer 3. The host computer 3 then dynamically adjusts the flow rate of the solenoid valve 2 based on the target grip force, forming a closed-loop control of the air pressure within the air pipe 4.

[0026] The steering wheel clamp 6 is made of non-metallic materials and includes two types: suction cup clamp 61 and base clamp 62. The suction cup clamp 61 is suitable for test scenarios where it can be quickly installed through the car window glass, while the base clamp 62 is suitable for test scenarios where the interior space of the vehicle allows or requires permanent fixation.

[0027] like Figure 2 As shown, the suction cup clamp 61 includes a suction cup 611, a multi-link robotic arm 9, and a steering wheel clamping mechanism 10. The suction cup 611 is a non-metallic suction cup with high load-bearing capacity, which can be firmly attached to the surface of the car window glass to provide stable support for the suction cup clamp 61.

[0028] like Figure 3 As shown, the base-type clamp 62 includes a base 621, a multi-link robotic arm 9, and a steering wheel clamping mechanism 10. The base 621 is made of non-metallic material and can be fixed to the vehicle seat rail or a specific position in the chassis through straps, buckles, or other structures, providing an extremely stable installation base.

[0029] like Figure 4 As shown, the multi-link robotic arm 9 is composed of multiple joint robotic arms 91, made of high-strength engineering plastic. Each joint robotic arm 91 is connected to a pneumatic telescopic cylinder 12 via plastic screws 11. The extension and retraction of the pneumatic telescopic cylinder 12 are controlled by a pneumatic control device 5, thereby realizing the rotation of each joint robotic arm 91 around its connection with other joint robotic arms 91, so as to adjust the unfolding angle and spatial posture of the multi-link robotic arm 9.

[0030] like Figure 5 As shown, the steering wheel clamping mechanism 10 consists of a first clamping mechanical arm 101 and a second clamping mechanical arm 102. The first clamping mechanical arm 101 and the second clamping mechanical arm 102 are connected to a pneumatic telescopic cylinder 12 by a plastic screw 11. The pneumatic control device 5 controls the extension and retraction of the pneumatic telescopic cylinder 12, thereby causing the first clamping mechanical arm 101 and the second clamping mechanical arm 102 to move away from or closer to each other, so as to realize the separation of the steering wheel 8 and the gripping of different strengths. The contact ends of the first clamping mechanical arm 101 and the second clamping mechanical arm 102 with the steering wheel 8 are detachable to adapt to steering wheels 8 of different sizes.

[0031] Camera 7 is connected to host computer 3 to monitor the relative position and movement status of steering wheel clamp 6 and steering wheel 8 in real time, and feeds back the collected video signals to host computer 3, forming a visual closed-loop feedback. Host computer 3 can analyze video frames through image recognition algorithms to verify whether steering wheel clamping mechanism 10 is accurately aligned with the target gripping area of ​​the steering wheel, and whether the clamping or releasing action is performed correctly. If there is a positional deviation or abnormal movement, the output pressure of pneumatic control device 5 or the posture of multi-link robotic arm 9 can be adjusted in time to ensure the accuracy and consistency of the test action, while avoiding test failure due to mechanical failure or pneumatic fluctuations.

[0032] Example 2 A test method for a steering wheel hands-off alarm triggering test system applied in complex electromagnetic environments, such as... Figure 6 As shown, it includes the following steps: S1. Based on the internal space of the vehicle under test, select a suitable steering wheel clamp 6 for installation and fixation. The vehicle under test is placed in an anechoic chamber.

[0033] If the vehicle to be tested needs to be quickly installed through the window glass, select the suction cup clamp 61 and attach it to the smooth surface of the windshield or side window glass using the non-metallic high load-bearing suction cup 611.

[0034] If a permanent fixation test is required, select the base-type clamp 62 and secure it to the vehicle seat rail or chassis preset position using non-metallic straps or buckles to ensure that the clamp is installed securely and without looseness.

[0035] S2. Adjust the steering wheel clamp 6 so that it is aligned with the target grip area of ​​the steering wheel 8.

[0036] Loosen the plastic screws 11 at each joint, and control the extension and retraction of the pneumatic telescopic cylinder 12 via the pneumatic control device 5. This allows each joint robotic arm 91 to rotate around its connection point with other joint robotic arms 91, adjusting the unfolding angle and spatial posture of the multi-link robotic arm 9. This ensures that the clamping area formed by the first clamping robotic arm 101 and the second clamping robotic arm 102 is precisely aligned with the 3 o'clock, 9 o'clock, or other preset gripping positions on the steering wheel 8. The host computer 3 controls the pneumatic control device 5 to drive the clamping mechanism 10 to perform a pre-clamping action. The clamping position accuracy is verified in real time using video signals collected by the camera 7. If a deviation exists, the angle of the pneumatic rotating joint is finely adjusted. After confirming that the alignment accuracy meets the test requirements, tighten the plastic screws at each joint to lock the posture of the multi-link robotic arm 9, ensuring that the clamping mechanism 10 will not shift or shake during the test.

[0037] The types of sensors tested on the vehicle under test include capacitive sensors, pressure sensors, and torque sensors. When testing capacitive sensors, metal foil or special electrode plates that mimic the capacitance characteristics of a human hand are attached to the contact ends of the first gripping robotic arm 101 and the second gripping robotic arm 102. When testing pressure sensors and torque sensors, the first gripping robotic arm 101 and the second gripping robotic arm 102 are used directly for gripping to simulate hand mechanical input.

[0038] S3. The host computer 3 sets the force, action sequence and duration of the simulated human hand grip, and controls the steering wheel clamp 6 to perform one calibration cycle. The video signal fed back by the camera 7 confirms the clamping position accuracy, and the air pressure detection unit built into the pneumatic control device 5 calibrates the pressure mapping relationship.

[0039] The host computer 3 controls the pneumatic control device 5 to drive the steering wheel clamping mechanism 10 to perform a complete calibration cycle according to the set parameters: first, it controls the first clamping robotic arm 101 and the second clamping robotic arm 102 to close to the target gripping force, hold for a set time, and then release and reset. During the calibration process, the camera 7 collects images of the relative position of the clamping mechanism 10 and the steering wheel 8 in real time. The host computer 3 compares the deviation between the actual clamping position and the preset target area through an image recognition algorithm. If the deviation exceeds the allowable range, it automatically issues a position adjustment command. At the same time, the air pressure detection unit built into the pneumatic control device 5 collects the actual air pressure value in the pneumatic circuit in real time. The host computer 3 calibrates the mapping relationship between the actual air pressure and the target gripping force, establishes a linear correspondence between "air pressure and gripping force", generates a pressure calibration curve and stores it for automatic matching of the required output air pressure according to the target gripping force in subsequent tests.

[0040] S4. According to the preset electromagnetic compatibility test standard, apply complex electromagnetic interference of specific frequency and field strength to the steering wheel area 8 through an electromagnetic interference source in an anechoic chamber.

[0041] The host computer (3) retrieves electromagnetic compatibility (EMC) test cases conforming to standards such as ISO 11452-2 or GB / T 33014, setting the frequency range of the interference signal (e.g., 100MHz to 6GHz), modulation method (e.g., AM modulation), and sweep step size. The system controls the operation of EMC sources (e.g., signal generators, power amplifiers, and radiating antennas) within the anechoic chamber, monitoring the actual field strength value in real time using field strength probes positioned around the steering wheel (8), ensuring it remains within the target range (e.g., 50V / m to 200V / m) and is evenly distributed. This complex EMC is continuously applied during the test, simulating the electromagnetic radiation environment generated by radar, base stations, or other electronic devices that a vehicle might encounter during actual driving, providing test conditions to verify the reliability of the hands-free alarm system under extreme electromagnetic environments.

[0042] S5. The host computer 3 controls the pneumatic control device 5 to drive the steering wheel clamp 6 to perform release and clamping actions according to the preset test cases, simulating the human hand leaving the steering wheel 8 and gripping it with different strengths, and monitors the triggering status of the hand-off alarm signal in real time through the vehicle's CAN bus.

[0043] Typical test cases include: Baseline confirmation: Keep the steering wheel clamp 6 loose and confirm that the vehicle hands-off warning system is in the alarm state.

[0044] Simulated grip: The host computer 3 sends a command to drive the steering wheel clamp 6 to clamp the steering wheel with a set target pressure (e.g., 10N). The pressure is kept stable by the air pressure detection unit built into the pneumatic control device 5, and the video signal collected by the camera 7 confirms that the steering wheel clamp 6 and the steering wheel 8 are clamped in place.

[0045] Anti-interference stability test: Under continuous electromagnetic interference, maintain the clamped state for a period of time (e.g., 60 seconds) and monitor whether the vehicle's hands-off alarm system will trigger a false alarm.

[0046] Simulated hand-off: Control the steering wheel clamp 6 to quickly release the steering wheel.

[0047] Alarm performance test: A high-precision timer is used to record the delay time from the completion of the release action to the triggering of the hands-off alarm system, and to monitor for any missed alarms.

[0048] Boundary and pressure gradient test: Repeat the above steps, changing the grip force (e.g., 5N, 15N) or electromagnetic interference intensity to test the performance of the vehicle's hands-off alarm system under different boundary conditions.

[0049] S6. The host computer 3 synchronously records the timestamp, command pressure, feedback air pressure, video confirmation frame, off-hand alarm signal and environmental field strength data during the test process, and automatically calculates the false alarm rate, missed alarm rate and alarm delay time to generate a test report.

[0050] S7. Control the steering wheel clamp 6 to return to the safe position via the host computer 3, shut off the solenoid valve 2 and the electromagnetic interference source, and end the test.

[0051] The rest is the same as in Example 1.

[0052] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A steering wheel hands-off alarm triggering test system applied in complex electromagnetic environments, characterized in that, include: The system comprises a compressed air tank (1), a solenoid valve (2), a host computer (3), an air pipe (4), a pneumatic control device (5), a steering wheel clamp (6), and a camera (7). The compressed air tank (1) is used to store compressed air. The solenoid valve (2) is connected to the host computer (3) and is used to receive instructions from the host computer (3) to control the flow, volume, and direction of compressed air in the air pipe (4). One end of the pneumatic control device (5) is connected to the solenoid valve (2) through the air pipe (4), and the other end is connected to the steering wheel clamp (6) through the air pipe (4). It is used to simulate the test action of a human hand on the steering wheel (8) through the steering wheel clamp (6). The pneumatic control device (5) has a built-in air pressure detection unit, which is connected to the host computer (3) to collect air pressure data in the pneumatic control device (5) in real time and feed it back to the host computer (3) so that the host computer (3) can dynamically adjust the flow of the solenoid valve (2) according to the target grip force to form a closed-loop control of the air pressure in the air pipe (4); the steering wheel clamp (6) is installed in the vehicle under test in the anechoic chamber; the camera (7) is connected to the host computer (3) to monitor the relative position and action status of the steering wheel clamp (6) and the steering wheel (8) in real time, and feed the collected video signal back to the host computer (3) to form a visual closed-loop feedback.

2. The steering wheel hands-off alarm triggering test system applied to complex electromagnetic environments according to claim 1, characterized in that, The test action of simulating human hand on steering wheel (8) by steering wheel clamp (6) includes leaving steering wheel (8) and gripping it with different force.

3. The steering wheel hands-off alarm triggering test system applied to complex electromagnetic environments according to claim 1, characterized in that, The steering wheel clamp (6) is made of non-metallic material and includes two types: suction cup clamp (61) and base clamp (62). The suction cup clamp (61) is suitable for test scenarios where it can be quickly installed through the car window glass, and the base clamp (62) is suitable for test scenarios where the interior space of the vehicle allows or requires permanent fixation.

4. The steering wheel hands-off alarm triggering test system for complex electromagnetic environments according to claim 3, characterized in that, The suction cup clamp (61) includes a suction cup (611), a multi-link robotic arm (9), and a steering wheel clamping mechanism (10). The suction cup (611) is firmly attached to the surface of the car window glass.

5. The steering wheel hands-off alarm triggering test system for complex electromagnetic environments according to claim 3, characterized in that, The base-type clamp (62) includes a base (621), a multi-link robotic arm (9), and a steering wheel clamping mechanism (10). The base (621) is fixed on the vehicle seat rail or at a specific position on the chassis inside the vehicle.

6. The steering wheel hands-off alarm triggering test system for complex electromagnetic environments according to claim 5, characterized in that, The multi-link robotic arm (9) is composed of multiple joint robotic arms (91) made of high-strength engineering plastic. Each joint robotic arm (91) is connected to a pneumatic telescopic cylinder (12) by plastic screws (11). The pneumatic telescopic cylinder (12) is controlled by a pneumatic control device (5) to extend and retract, thereby realizing the rotation of each joint robotic arm (91) around the connection point with other joint robotic arms (91) to adjust the unfolding angle and spatial posture of the multi-link robotic arm (9).

7. The steering wheel hands-off alarm triggering test system for complex electromagnetic environments according to claim 5, characterized in that, The steering wheel clamping mechanism (10) consists of a first clamping mechanical arm (101) and a second clamping mechanical arm (102). The first clamping mechanical arm (101) and the second clamping mechanical arm (102) are connected to a pneumatic telescopic cylinder (12) by a plastic screw (11). The pneumatic telescopic cylinder (12) is controlled to extend and retract by a pneumatic control device (5), thereby causing the first clamping mechanical arm (101) and the second clamping mechanical arm (102) to move away from or closer to each other, so as to achieve the separation of the steering wheel (8) and the gripping of different strengths.

8. The steering wheel hands-off alarm triggering test system for complex electromagnetic environments according to claim 7, characterized in that, The first gripping robotic arm (101) and the second gripping robotic arm (102) are detachable from the contact ends of the steering wheel (8) to accommodate steering wheels (8) of different sizes.

9. A test method for a steering wheel hands-off alarm triggering test system applied in a complex electromagnetic environment, characterized in that, The steering wheel hands-off alarm triggering system of the vehicle under test is tested using the steering wheel hands-off alarm triggering test system for complex electromagnetic environments as described in claim 1, including the following steps: Based on the internal space of the vehicle under test, a suitable steering wheel clamp (6) is selected, and the vehicle under test is placed in an anechoic chamber; Adjust the steering wheel clamp (6) so that it is aligned with the target grip area of ​​the steering wheel (8); The host computer (3) sets the force, action sequence and duration of the simulated human hand grip, and controls the steering wheel clamp (6) to perform a calibration cycle. The clamping position accuracy is confirmed by the video signal fed back by the camera (7), and the pressure mapping relationship is calibrated by the air pressure detection unit built into the pneumatic control device (5). According to the preset electromagnetic compatibility test standard, complex electromagnetic interference with specific frequency and field strength is applied to the steering wheel (8) area through an electromagnetic interference source in an anechoic chamber. The host computer (3) controls the pneumatic control device (5) to drive the steering wheel clamp (6) to perform the release and clamping actions according to the preset test cases, simulating the human hand leaving the steering wheel (8) and gripping it with different strengths, and monitors the triggering status of the hand-off alarm signal in real time through the vehicle's CAN bus. The host computer (3) synchronously records the timestamp, command pressure, feedback air pressure, video confirmation frame, off-hand alarm signal and environmental field strength data during the test process, and automatically calculates the false alarm rate, missed alarm rate and alarm delay time to generate a test report. The host computer (3) controls the steering wheel clamp (6) to return to the safe position, closes the solenoid valve (2) and the electromagnetic interference source, and ends the test.

10. The test method for the steering wheel hands-off alarm triggering test system applied to complex electromagnetic environments according to claim 9, characterized in that, The types of sensors tested on the vehicle under test include capacitive sensors, pressure sensors, and torque sensors. When testing the capacitive sensors, metal foil or special electrode sheets that mimic the capacitance characteristics of a human hand are attached to the contact ends of the first clamping robotic arm (101) and the second clamping robotic arm (102). When testing the pressure sensors and torque sensors, the first clamping robotic arm (101) and the second clamping robotic arm (102) are used directly for clamping to simulate the mechanical input of the hand.

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