Brake pedal signal backup system based on uwb detection of driver foot position

Abstract

The patent application belongs to the technical field of brake system, and particularly relates to a brake pedal signal backup system based on UWB detection of driver's foot position, which comprises a UWB signal transmitting module, a UWB signal receiving module, a UWB processing module and a main MCU. When the main signal transmission unit works normally, the main control signal generated by the brake pedal sensor is transmitted to the main MCU, and the UWB signal transmitting module transmits a low-frequency synchronization signal. When the main signal transmission unit works abnormally, the UWB processing module switches, so that the UWB signal transmitting module transmits an ultra-wideband signal to the UWB signal receiving module. The ultra-wideband signal comprises a foot position signal. The UWB processing module processes the ultra-wideband signal to obtain a backup control signal and transmits the backup control signal to the main MCU. The main MCU can switch to the backup control signal for control in time when the main signal transmission unit works abnormally, thereby ensuring driving safety.

Description

Technical Field

[0001] This invention relates to the field of braking system technology, and more specifically to a brake pedal signal backup system based on UWB detection of the driver's foot position. Background Technology

[0002] In automotive braking systems, accurate transmission of brake pedal signals plays a crucial role in ensuring safe braking. Traditional brake pedal signal transmission primarily relies on wired connections or single wireless transmission methods, such as CAN bus or Bluetooth. The main control signal generated by the brake pedal sensor is transmitted to the main MCU via the main signal transmission unit, and the main MCU controls the braking mechanism to perform braking based on the main control signal.

[0003] However, wired connections may have risks of aging lines, short circuits, open circuits, etc., while using a single wireless transmission method is prone to signal interruption or errors when faced with strong electromagnetic interference or signal obstruction. These problems may cause the brake pedal signal to fail to be transmitted to the brake control unit normally, thereby endangering the vehicle's driving safety. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a brake pedal signal backup system based on UWB detection of the driver's foot position, which can switch to the backup control signal in a timely manner when the main signal transmission unit malfunctions, thus ensuring driving safety.

[0005] The technical solution adopted in this invention is as follows:

[0006] A brake pedal signal backup system based on UWB detection of driver's foot position includes a main MCU. When the main signal transmission unit is working normally, it transmits the main control signal generated by the brake pedal sensor to the main MCU. The main MCU controls the braking mechanism to perform braking based on the main control signal. The system also includes a UWB backup signal transmission unit, which comprises a UWB signal transmitting module, a UWB signal receiving module, and a UWB processing module. When the main signal transmission unit malfunctions, the UWB signal transmitting module transmits an ultra-wideband signal, including a foot position signal, to the UWB signal receiving module. The UWB processing module processes the ultra-wideband signal to obtain a backup control signal, which is then transmitted to the main MCU. The main MCU controls the braking mechanism to perform braking based on the backup control signal.

[0007] Working principle: The main signal transmission unit adopts the conventional brake control method in existing automobiles, including a brake pedal sensor connected to the main MCU. The main control signal generated by the brake pedal sensor is transmitted to the main MCU, which controls the braking mechanism to perform braking through the main control signal. When the main signal transmission unit malfunctions, it can immediately switch to the UWB signal transmission module to transmit an ultra-wideband signal to the UWB signal receiving module, and control the braking mechanism through the backup control signal to ensure the normal operation of the braking mechanism. Although the accuracy of foot signal position acquisition using UWB technology is lower than that of the brake pedal sensor, it can meet the requirements of use as a backup system for brake pedal signals.

[0008] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0009] 1. By adopting UWB technology, it is easy to combine ranging and communication. Moreover, the UWB signal transmitting module itself has an adaptive power adjustment function, which can automatically adjust the transmission power according to the distance and signal strength between it and the UWB signal receiving module to ensure stable signal transmission and make the signal more stable. Therefore, the brake pedal signal backup system of the present invention can work normally when facing strong electromagnetic interference, signal blockage and other situations.

[0010] 2. In the event of a failure in the main control signal unit, the brake pedal signal backup system of this invention can be used for brake control, reducing the possibility of brake failure during driving and improving driving safety.

[0011] In a preferred embodiment of the present invention, when the main signal transmission unit is working normally, the UWB signal transmitting module transmits a synchronization signal to the UWB signal receiving module to maintain connection with the UWB signal receiving module.

[0012] Beneficial effects: By transmitting a synchronization signal from the UWB signal transmitting module to the UWB signal receiving module, the UWB signal transmitting module and the UWB signal receiving module maintain a connection, thereby confirming that the signal backup system is in normal working condition. This avoids the system being unable to function properly when switching to the backup system, thus preventing any impact on driving safety.

[0013] In a preferred embodiment of the present invention, the synchronization signal is a low-frequency synchronization signal.

[0014] Beneficial effect: Since the synchronization signal transmitted by the UWB signal transmitting module is only used for verification, a low-frequency synchronization signal can be used to reduce power consumption.

[0015] In a preferred embodiment of the present invention, the UWB processing module monitors the working status of the main signal transmission unit in real time. When the main signal transmission unit is abnormal, the UWB processing module controls the UWB signal transmission module to switch from transmitting the synchronization signal to transmitting the ultra-wideband signal.

[0016] Beneficial effects: The UWB processing module has real-time monitoring and switching functions to ensure that when the main signal transmission unit malfunctions, it can switch to the ultra-wideband signal in a timely manner, which is beneficial for the main MCU to control.

[0017] In a preferred embodiment of the present invention, the synchronization signal includes a foot position signal, and the UWB processing module processes the synchronization signal to obtain a verification signal.

[0018] Beneficial effects: While the main signal transmission unit is working, the UWB signal transmission module also transmits a low-frequency synchronization signal; the main MCU can obtain the main control signal for the braking mechanism from the signal generated by the brake pedal sensor, and can also obtain the verification signal from the pedal position data in the low-frequency synchronization signal. By comparing the verification signal obtained from the low-frequency synchronization signal with the main control signal, it can be determined whether the main signal transmission unit is malfunctioning.

[0019] In a preferred embodiment of the present invention, when the main MCU does not receive the main control signal, but the UWB signal receiving module receives the synchronization signal, the UWB processing module determines that the signal is interrupted.

[0020] The main MCU compares the main control signal with the verification signal. When the error exceeds the preset range, the main MCU transmits the comparison result to the UWB processing module, and the UWB processing module determines that the signal is abnormal.

[0021] In the event of signal interruption or abnormality, the UWB processing module controls the UWB signal transmission module to switch from transmitting the synchronization signal to transmitting the ultra-wideband signal.

[0022] Beneficial effects:

[0023] 1. The main signal transmission unit may malfunction due to various reasons. When there is a problem with the internal circuit (such as a short circuit), the main MCU can diagnose its own fault. However, when the brake pedal sensor itself is damaged, or is blocked by signal or electromagnetic interference, the main MCU may no longer receive the corresponding signal and will not be able to diagnose its own malfunction. Therefore, this solution sets a low-frequency synchronization signal with pedal position data. Under low power consumption, the pedal position data of the low-frequency synchronization signal can be used as a reference for comparison. As long as the brake pedal position changes, the main MCU can receive the main control signal and the verification signal, and can detect whether the main signal transmission unit is malfunctioning in a timely manner.

[0024] 2. The pedal position data from the low-frequency synchronization signal can be used to directly control the braking mechanism. In case of emergency braking, the system can switch to the signal backup system in a timely manner to avoid short-term unresponsiveness of the braking mechanism and improve driving safety.

[0025] In a preferred embodiment of the present invention, both the synchronization signal and the ultra-wideband signal are transmitted using encryption.

[0026] Beneficial effects: Encrypted signal transmission prevents malicious tampering and ensures driving safety.

[0027] In a preferred embodiment of the present invention, the main MCU and the UWB processing module transmit signals through an SPI communication interface.

[0028] Beneficial effects: SPI supports high data transfer rates, making it suitable for applications requiring rapid transmission of large amounts of data. Furthermore, SPI allows for simultaneous bidirectional data transmission, improving communication efficiency. Attached Figure Description

[0029] Figure 1 This is a circuit diagram of an embodiment of the brake pedal signal backup system based on UWB detection of the driver's foot position according to the present invention. Detailed Implementation

[0030] Typical embodiments embodying the features and advantages of the present invention will be specifically described in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0031] In the description of this application, the terms "first", "second", etc. are used only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the structure referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0032] See Figure 1 As shown, the brake pedal signal backup system based on UWB detection of the driver's foot position disclosed in this embodiment includes a UWB signal transmitting module, a UWB signal receiving module, a UWB processing module, and a main MCU. When the main signal transmitting unit is working normally, it transmits the main control signal generated by the brake pedal sensor to the main MCU. The main MCU controls the braking mechanism to brake according to the main control signal. At the same time, the UWB signal transmitting module transmits a low-frequency synchronization signal to the UWB signal receiving module to maintain connection with the UWB signal receiving module. When the main signal transmitting unit malfunctions, the UWB signal transmitting module transmits an ultra-wideband signal to the UWB signal receiving module. The ultra-wideband signal includes a foot position signal. The UWB processing module processes the ultra-wideband signal to obtain a backup control signal and transmits it to the main MCU. The main MCU controls the braking mechanism to brake according to the backup control signal.

[0033] The UWB processing module uses a UWB integrated chip (model DW1000), and the UWB receiving module uses an antenna. An inductor is set between the antenna and pins 16 and 17 of the UWB integrated chip. A crystal oscillator is connected to pins 3 and 4 of the UWB integrated chip. Pin 47 of the UWB integrated chip is connected to the power supply circuit. Pins 39, 40, and 41 of the UWB integrated chip are connected to the SPI communication interface and are connected to the main MCU through the SPI transmission line. By monitoring the foot position change through UWB radar, a low-frequency synchronization signal including the foot position signal can be obtained. The frequency can also be increased to obtain an ultra-wideband signal. The UWB processing module processes the synchronization signal to obtain a verification signal and processes the ultra-wideband signal to obtain a backup control signal.

[0034] Among them, when the main signal transmission unit is working normally, the main control signal generated by the brake pedal sensor is transmitted to the main MCU (model Aurix TC234L). The main MCU transmits the control signal to the three-phase bridge pre-drive chip according to the main control signal. The voltage is amplified by the three-phase bridge pre-drive chip and then driven by the corresponding three-phase drive bridge to drive the three-phase brushless motor to work, thereby performing braking.

[0035] It also includes a power management chip (model TLF35584), and the main control signal (pedal brake signal) is transmitted to the main MCU through a filter circuit; a surge protection unit and a power filter unit are set between the vehicle power supply system and the power management chip in sequence. The power management chip supplies power to loads of 5V and below. The output of the vehicle power supply system is connected in sequence to the surge protection unit and the EMC filter to supply power to the three-phase drive bridge.

[0036] The vehicle power supply system is connected to a voltage divider circuit, which is connected to the power management chip and the main MCU respectively. After the vehicle power supply system is ignited, the ignition signal can be transmitted to the power management chip and the main MCU respectively, thereby starting the braking system.

[0037] The main MCU is also connected to an ambient temperature measurement module and a drive section temperature measurement module, which are used to measure the ambient temperature and the temperature of the brake motor.

[0038] While the main signal transmission unit is working, the UWB signal transmitting module transmits a low-frequency synchronization signal to the UWB signal receiving module. The UWB processing module processes the synchronization signal to obtain a verification signal, which is then transmitted to the main MCU via the SPI transmission line. Therefore, the main MCU will receive both the verification signal and the main control signal simultaneously. The main MCU compares the two signals, and when the error between them exceeds a preset range, the comparison result is transmitted to the UWB processing module. The UWB processing module can determine that the signal is abnormal. When the UWB processing module receives the low-frequency synchronization signal but the main MCU does not receive the main control signal, it can determine that the signal is interrupted, indicating that the main signal transmission unit is malfunctioning.

[0039] When the main signal transmission unit malfunctions, the UWB processing module switches, causing the UWB transmitting module to increase the frequency of the low-frequency synchronization signal and transmit an ultra-wideband signal. The UWB processing module processes the ultra-wideband signal to obtain a backup control signal, which is then transmitted to the main MCU via the SPI transmission line. The main MCU uses only the backup control signal to control the braking mechanism for braking.

[0040] The synchronization signal and ultra-wideband signal are encrypted using AES-128. The DW1000 chip supports the AES-128 symmetric encryption algorithm, which has high security and efficiency. In addition, the DW1000 chip has a built-in AES hardware acceleration module, which can efficiently perform encryption and decryption operations and reduce the burden of software processing.

[0041] Therefore, this solution has the following advantages:

[0042] When the main signal transmission unit is working normally, it operates at a low frequency, resulting in low power consumption. The low-frequency synchronization signal maintains the connection between the UWB transmitter and receiver and can be processed to obtain a verification signal. The main MCU can use the verification signal for judgment. It can promptly detect various faults in the main signal transmission unit, such as brake pedal sensor damage, signal shielding or interception, or circuit short circuit, and switch to ultra-wideband signal for control. Furthermore, when the main control signal is shielded or the brake pedal sensor is damaged, the main MCU may not be able to receive the signal at all. The verification signal can still be used as a preliminary control signal to control the control mechanism, ensuring a smooth switching between the main control signal and the backup control signal. This is especially crucial in emergency braking situations where the main signal transmission unit fails, ensuring driving safety.

[0043] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A brake pedal signal backup system based on UWB detection of driver's foot position, comprising a main MCU, wherein when the main signal transmission unit is working normally, it transmits the main control signal generated by the brake pedal sensor to the main MCU, and the main MCU controls the braking mechanism to perform braking according to the main control signal, characterized in that: It also includes a UWB backup signal transmission unit, which includes a UWB signal transmitting module, a UWB signal receiving module, and a UWB processing module. When the main signal transmission unit is working normally, the UWB signal transmitting module transmits a synchronization signal to the UWB signal receiving module to maintain connection with the UWB signal receiving module; the UWB processing module processes the synchronization signal to obtain a verification signal and transmits it to the main MCU through the SPI transmission line. The main MCU will receive the verification signal and the main control signal at the same time. The main MCU compares the two and transmits the comparison result to the UWB processing module. When the main signal transmission unit experiences various faults such as brake pedal sensor damage, signal shielding and interception, or circuit short circuit, it switches to ultra-wideband signal for control. When the main control signal is blocked or the brake pedal sensor is damaged, the verification signal can also be used as a preliminary control signal to control the control mechanism and ensure the smooth switching between the main control signal and the backup control signal. When the main signal transmission unit malfunctions, the UWB signal transmitting module transmits an ultra-wideband signal to the UWB signal receiving module, and the ultra-wideband signal includes a foot position signal. The UWB processing module processes the ultra-wideband signal to obtain a backup control signal, which is then transmitted to the main MCU via the SPI transmission line. The main MCU controls the braking mechanism to brake according to the backup control signal.

2. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 1, characterized in that: The synchronization signal is a low-frequency synchronization signal.

3. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 1, characterized in that: The UWB processing module monitors the working status of the main signal transmission unit in real time. When the main signal transmission unit is abnormal, the UWB processing module controls the UWB signal transmission module to switch from transmitting the synchronization signal to transmitting the ultra-wideband signal.

4. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 1 or 3, characterized in that: The synchronization signal includes a foot position signal, and the UWB processing module processes the synchronization signal to obtain a verification signal.

5. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 4, characterized in that: When the main MCU does not receive the main control signal, but the UWB signal receiving module receives the synchronization signal, the UWB processing module determines that the signal is interrupted. The main MCU compares the main control signal with the verification signal. When the error exceeds the preset range, the main MCU transmits the comparison result to the UWB processing module, and the UWB processing module determines that the signal is abnormal. In the event of signal interruption or abnormality, the UWB processing module controls the UWB signal transmission module to switch from transmitting the synchronization signal to transmitting the ultra-wideband signal.

6. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 1, characterized in that: Both the synchronization signal and the ultra-wideband signal are transmitted in encrypted form.

7. The brake pedal signal backup system based on UWB detection of driver's foot position according to claim 1, characterized in that: The main MCU and the UWB processing module transmit signals via an SPI communication interface.

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