An active pre-tightening seat belt control system driven by electricity and its implementation method

Abstract

This invention discloses an electrically driven active pretensioning seatbelt control system and its implementation method. The control system includes: an electronic control unit, an ADC sampling module, a CAN communication module, a Hall sensor module, a seatbelt latch, and a webbing winding device equipped with a motor. Through these modules, the electrically driven active pretensioning seatbelt control system of this invention achieves gap elimination and safe driving reminders in various states. This invention combines the traditional seatbelt structure with modern automotive electronic control technology by acquiring information about the vehicle and occupants from the communication and sensor modules through the electronic control unit. By controlling the motor rotation through various methods, it achieves gap elimination between the occupant and the seatbelt and provides safe driving reminders, thereby improving the safety and comfort of occupants in the vehicle.

Description

Technical Field

[0001] This invention relates to the field of automotive electronic control, and particularly to an electrically driven active pretensioning seat belt control system and its implementation method. It is applicable to gasoline-powered vehicles, new energy vehicles, and other applications where seat belts are installed. Background Technology

[0002] In recent years, automotive electronic control technology has developed rapidly, mainly due to the following three factors: First, the rapid development of transistor technology, large-scale integrated circuit technology, computer technology, and network technology has led to continuously decreasing costs and increasingly powerful control functions, providing favorable conditions for the development of automotive electronic control technology. Second, increasingly stringent regulations imposed by governments worldwide have forced automakers to adopt advanced electronic control technologies to meet regulatory requirements in terms of fuel economy, safety, and emissions performance. Third, users' increasing demands for vehicle safety, comfort, power, and economy have prompted automakers to adopt more electronic control technologies to enhance the competitiveness of their products in the market.

[0003] Car seat belts are widely recognized as the most affordable and effective safety device in automobiles. Their function is to restrain occupants during a collision and prevent them from secondary impacts with the steering wheel and dashboard, or from being ejected from the vehicle, resulting in injury or death. Thanks to advancements in automotive electronic control technology, seat belts have combined traditional mechanical structures with electronic controls, becoming safer, more comfortable, and smarter. The addition of electronic control technology allows seat belts to not only function during a collision but also provide early warnings during normal driving or dangerous driving situations, maximizing the safety performance they offer. Summary of the Invention

[0004] In view of the requirements mentioned above, the purpose of this invention is to provide an electrically driven active pretensioning seat belt control system and its implementation method, which realizes gap elimination and safe driving reminders in multiple states. The technical solution of this invention is as follows:

[0005] A seatbelt control system employing a DC motor for active pretensioning includes a seatbelt latch, an ADC sampling module, a Hall sensor module, a CAN communication module, an electronic control unit (ECU), and a webbing winding device equipped with a motor. The seatbelt latch converts the switch status of the seatbelt key into a digital signal and sends it to the ECU. The ADC sampling module converts the analog current signal of the motor into a digital signal and sends it to the ECU. The Hall sensor module senses disk pulses through a Hall element and converts the motor's position signal into a digital signal and sends it to the ECU. The CAN communication module includes receiving information from other devices on the CAN bus and sending it to the ECU, and receiving information to be sent from the ECU and sending it to the CAN bus for other devices to receive. The ECU analyzes and calculates the received seatbelt latch signal, ADC sampling module signal, Hall sensor signal, and CAN communication module signal to control the motor in the webbing winding device. Based on the signal output by the ECU, the motor in the webbing winding device rotates forward or backward to tighten or release the webbing.

[0006] The present invention provides a method for implementing an electrically driven active pretensioning seat belt control system, comprising the following steps:

[0007] When the occupant fastens the seatbelt, the electronic control unit (ECU) receives a switch signal from the seatbelt latch, closing the latch. Simultaneously, the ECU reads the vehicle speed signal via the CAN communication module. When the vehicle speed signal exceeds a certain value, it determines that the vehicle is in normal driving condition. At this point, the ECU uses a PWM signal to control the motor to rotate forward and tighten the webbing to eliminate the gap between the webbing and the occupant. The ECU uses the motor current signal to determine if the gap has been eliminated. When the gap is eliminated, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring. Through the CAN communication module, the occupant can set parameters such as the seatbelt tightening speed and tension via the vehicle's main control computer.

[0008] After the initial elimination of the seatbelt gap, the electronic control unit (ECU) acquires the webbing position signal after the gap is eliminated via the Hall sensor module. Simultaneously, the ECU obtains the difference between the current webbing position and the position after the gap is eliminated via the Hall sensor module. When this difference exceeds a certain value, the gap between the seatbelt and the occupant is too large. The ECU then controls the motor to rotate forward via a PWM signal to tighten the webbing and eliminate the gap. The ECU also uses the motor current signal to determine if the gap has been eliminated. When the gap is eliminated, the ECU controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring. During normal vehicle operation, the ECU acquires the vehicle speed signal via the CAN communication module. When the vehicle speed exceeds a certain value, the vehicle is speeding. The ECU then controls the motor to rotate forward and backward at a certain frequency via a PWM signal to control the intermittent contraction and release of the webbing, reminding the occupant to be aware of safety. Furthermore, through the CAN communication module, the occupant can set parameters such as the seatbelt tightening speed, tension, frequency, and number of tightening cycles via the vehicle's main control computer.

[0009] When the occupant unbuckles the seatbelt, the electronic control unit (ECU) receives a switch signal from the seatbelt latch, opening the latch. Simultaneously, the ECU reads the vehicle speed signal via the CAN communication module. When the vehicle speed signal is 0, it indicates the vehicle is stationary. The ECU then uses the Hall sensor module to read the webbing position to determine if the webbing is fully retracted. If not, the ECU uses a PWM signal to control the motor to rotate forward and tighten the webbing, ensuring it is fully retracted into the winding device. The ECU also uses the motor current signal to determine if the webbing is tightened. When the webbing is tightened, the ECU controls the motor to rotate in reverse, releasing part of the webbing and simultaneously resetting the coil spring. Through the CAN communication module, the occupant can set parameters such as the seatbelt tightening speed and tension via the vehicle's main control computer.

[0010] The present invention has the following beneficial effects:

[0011] 1. This invention makes full use of the mechanical structure of traditional car seat belts. It can meet most requirements even when the intelligence level of the car's main control computer is not high. It has the characteristics of good popularity and simple implementation.

[0012] 2. This invention combines the traditional mechanical structure of car seat belts with modern automotive electronic control technology, which not only ensures the original function of seat belts, but also provides early warnings during normal driving or dangerous driving, thus maximizing the safety performance provided by car seat belts.

[0013] 3. This invention enables interaction between the seatbelt electronic control unit and the vehicle's main control computer via a CAN communication module. Vehicle occupants can set various parameters for seatbelt control through the vehicle's main control computer, further enhancing personalization and intelligence. Attached Figure Description

[0014] Figure 1 : Overall block diagram of active pretensioning seat belt control system.

[0015] Figure 2 Hardware block diagram of the active pretensioning seat belt electronic control unit.

[0016] Figure 3 Method 1 implements the control flow diagram.

[0017] Figure 4 Method 2: Gap Elimination Control Flowchart.

[0018] Figure 5 Method 2: Safety Reminder Implementation Control Flowchart.

[0019] Figure 6 Method 3 implements the control flow diagram.

[0020] Figure 7 CAN communication block diagram between the vehicle's main control unit and the seat belt electronic control unit. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention. Those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

[0022] like Figure 1 As shown, the Electronic Control Unit (ECU) obtains the seatbelt buckle status via a switch signal and acquires information from other vehicle devices via a CAN signal. The ECU sends a PWM signal to control the motor's rotation, and simultaneously obtains current feedback and Hall position feedback from the motor via an ADC module and a Hall sensor module. Based on the feedback signals, the ECU compensates for the PWM signal to control the motor's rotation. The motor's rotation causes mechanical transmission in the webbing take-up unit, generating webbing force to tighten the webbing.

[0023] like Figure 2 As shown, the Electronic Control Unit (ECU) mainly receives switch signals, Hall effect signals, current signals, and CAN signals, which are obtained from the seatbelt latch, Hall effect sensor module, ADC sampling module, and CAN communication module, respectively. The ECU outputs a PWM signal to control the motor rotation.

[0024] like Figure 3As shown, when the occupant fastens the seatbelt, the electronic control unit receives a latch switch signal, and the latch closes. After the vehicle starts moving normally, the electronic control unit reads the vehicle speed signal via the CAN communication module. When the vehicle speed signal exceeds a certain value, the electronic control unit controls the motor to rotate forward via a PWM signal to tighten the webbing and eliminate the gap between the webbing and the occupant. The electronic control unit determines whether the gap has been eliminated by using the motor current signal. When the gap is eliminated, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring.

[0025] like Figure 4 As shown, after the car is in normal operation, the gap between the seatbelt and the occupant is eliminated for the first time. The electronic control unit (ECU) acquires the webbing position signal (hall) after the first elimination of the seatbelt gap via the Hall sensor module. Simultaneously, the ECU acquires the difference between the current webbing position and the position after the safety gap is eliminated via the Hall sensor module. When the difference signal exceeds a certain value, the gap between the seatbelt and the occupant is too large. The ECU then controls the motor to rotate forward via a PWM signal to tighten the webbing and eliminate the gap. The ECU determines whether the gap has been eliminated via the motor current signal. When the gap is eliminated, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring.

[0026] like Figure 5 As shown, the seatbelt is first eliminated from the gap between itself and the occupant after the car has started moving normally. The electronic control unit (ECU) reads the car's speed signal via the CAN communication module. When the car's speed signal exceeds a certain value, the car is in an overspeeding state. The ECU then uses a PWM signal to control the motor to rotate forward and backward at a certain frequency to control the intermittent contraction and release of the webbing, reminding the occupant to pay attention to safety. Simultaneously, through the CAN communication module, the occupant can set parameters such as the seatbelt tightening speed, tension, frequency, and number of tightening cycles via the car's control terminal.

[0027] like Figure 6 As shown, when the occupant unbuckles the seatbelt, the electronic control unit (ECU) receives a latch switch signal, and the latch opens. Simultaneously, the ECU reads the vehicle speed signal via the CAN communication module; when the vehicle speed signal is 0, the vehicle is stationary. The ECU reads the webbing position via the Hall sensor module to determine if the webbing is fully retracted. If not fully retracted, the ECU controls the motor to rotate forward via a PWM signal to tighten the webbing, ensuring it is fully retracted into the winding device. The ECU also uses the motor current signal to determine if the webbing is tightened; when the webbing is tightened, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring.

[0028] like Figure 7As shown, the CAN communication between the vehicle's main control unit (VCU) and the seatbelt electronic control unit (ECU) includes: the VCU sending differential signals CANH and CANL to the CAN bus; the CAN transceiver receiving the differential signals and converting them into digital signals RXD and TXD, which are then sent to the ECU; the ECU then sends PWM signals to control the motor based on these signals. Conversely, the ECU sends RXD and TXD digital signals to the CAN transceiver, which converts the digital signals into differential signals CANH and CANL and sends them to the CAN bus for the VCU to receive.

[0029] This invention discloses an electrically driven active pretensioning seatbelt control system and its implementation method. The control system includes: an electronic control unit, an ADC sampling module, a CAN communication module, a Hall sensor module, a seatbelt latch, and a webbing winding device equipped with a motor. Through the above modules, the electrically driven active pretensioning seatbelt control system of this invention achieves gap elimination and safe driving reminders in various states, including the following methods.

[0030] Step 1: After the occupant has fastened their seatbelt, the electronic control unit uses the switch signal of the seatbelt buckle and the vehicle speed signal obtained through CAN communication to notify the motor to work after the car is running normally, so as to eliminate the webbing gap with a lower webbing tension.

[0031] Step 2: During vehicle operation, if the gap between the webbing and the occupant becomes too large due to occupant movement, the electronic control unit detects the Hall sensor signal and instructs the motor to operate, using a lower webbing tension to eliminate the webbing gap. When the vehicle speed is too high or the occupant's driving condition is detected to be poor, the electronic control unit receives the CAN signal and instructs the motor to operate, using a moderate webbing tension to tighten the webbing. At the same time, the motor alternates between forward and reverse rotation to remind the occupant to pay attention to safety.

[0032] Step 3: After the occupant unbuckles the seatbelt, the electronic control unit confirms that the car is stationary via the CAN signal. Then, by detecting the seatbelt latch switch signal and the Hall sensor signal, it controls the spring in the motor-assisted webbing winding device to completely retract the webbing into the webbing winding device.

[0033] This invention uses an electronic control unit to acquire information about the vehicle and its occupants from various communication and sensor modules. It combines the traditional seatbelt structure with modern automotive electronic control technology and uses multiple methods to control the motor rotation to eliminate the gap between the occupant and the seatbelt and provide safe driving reminders, thereby improving the safety and comfort of the occupants in the vehicle.

Claims

1. A method for implementing an electrically driven active pretensioning seatbelt control system, characterized in that, Includes the following steps: Step 1: After the occupant fastens the seatbelt, the electronic control unit (ECU) receives a switch signal from the seatbelt latch, closing the latch. Simultaneously, the ECU reads the vehicle speed signal via the CAN communication module. When the vehicle speed signal exceeds a certain value, it determines that the vehicle is in normal driving condition. At this time, the ECU controls the motor to rotate forward via a PWM signal to tighten the webbing and eliminate the gap between the webbing and the occupant. The ECU determines whether the gap has been eliminated via the motor current signal. When the gap is eliminated, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring. Through the CAN communication module, the occupant can set the seatbelt tightening speed and tension parameters via the vehicle's main control computer. Step 2: After the initial elimination of the seatbelt gap, the electronic control unit (ECU) acquires the webbing position signal after the gap is eliminated via the Hall sensor module. Simultaneously, the ECU acquires the difference between the current webbing position and the position after the gap is eliminated via the Hall sensor module. When this difference exceeds a certain value, the gap between the seatbelt and the occupant is too large. The ECU then controls the motor to rotate forward via a PWM signal to tighten the webbing and eliminate the gap. The ECU also uses the motor current signal to determine if the gap has been eliminated. When the gap is eliminated, the ECU controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring. During normal vehicle operation, the ECU acquires the vehicle speed signal via the CAN communication module. When the vehicle speed signal exceeds a certain value, the vehicle is speeding. The ECU controls the motor to rotate forward and backward at a certain frequency via a PWM signal to control the intermittent contraction and release of the webbing, reminding the occupant to pay attention to safety. Furthermore, through the CAN communication module, the occupant can set the seatbelt tightening speed, tension, frequency, and number of tightening cycles via the vehicle's main control computer. Step 3: After the occupant unbuckles the seatbelt, the electronic control unit (ECU) receives a switch signal from the seatbelt latch, opening the latch. Simultaneously, the ECU reads the vehicle speed signal via the CAN communication module. When the vehicle speed signal is 0, it indicates the vehicle is stationary. The ECU then uses the Hall sensor module to read the webbing position to determine if the webbing is fully retracted. If not fully retracted, the ECU uses a PWM signal to control the motor to rotate forward and tighten the webbing, ensuring it is fully retracted into the winding device. The ECU uses the motor current signal to determine if the webbing is tightened. When the webbing is tightened, it controls the motor to rotate in reverse to release part of the webbing and simultaneously reset the coil spring. Through the CAN communication module, the occupant can set the seatbelt tightening speed and tension parameters via the vehicle's main control computer.

2. The method for implementing an electrically driven active pretensioning seatbelt control system according to claim 1, characterized in that: The seatbelt control system includes a seatbelt latch, an ADC sampling module, a Hall sensor module, a CAN communication module, an electronic control unit, and a webbing winding device equipped with a motor. The seatbelt latch converts the on / off state of the seatbelt key into a digital signal and sends it to the electronic control unit. The ADC sampling module converts the analog current signal of the motor into a digital signal and sends it to the electronic control unit. The Hall sensor module senses disk pulses through Hall elements and converts the motor position signal into a digital signal and sends it to the electronic control unit. The CAN communication module includes receiving information sent by other devices from the CAN bus and sending it to the electronic control unit, and receiving information to be sent from the electronic control unit and sending it to the CAN bus for other devices to receive. The electronic control unit analyzes and calculates the received seatbelt latch signal, ADC sampling module signal, Hall sensor signal, and CAN communication module signal, and then controls the motor in the webbing winding device. The webbing winding device equipped with a motor rotates forward or backward according to the signal output by the electronic control unit to tighten or release the webbing.

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