With the rapid development of the information industry, simple control and operation of machines can no longer meet the desires of human beings, and the use of speech recognition technology to make machines understand human language and realize human-computer interaction has become a new research content. For users, this human-computer interaction should be the most natural way. At the same time, people's time in the car can also produce many comprehensive benefits, which will become the focus of competition among automobile manufacturers in the future. Traditional in-vehicle terminals with a large number of physical buttons are undoubtedly distracting and dangerous. In this case, voice recognition technology is increasingly applied to cars to achieve some intelligent operations. In-vehicle voice recognition technology, which enables car owners to "only move their mouths and not their hands", will be a very effective solution.
1.1. Human-computer interaction module
The module uses the Bluetooth headset as the carrier to send request commands to the on-board terminal or actively receive push information to monitor and display the operating status parameters of the vehicle in real time. The solution adopts a multi-agent-based, task-oriented human-computer interaction framework. Through the human-computer interaction module, the human command is converted into the signal controlled by the ECU of the car, so that the person and the car are harmoniously unified. Bluetooth is the hardware foundation for wireless communication. The solution uses ROK101007 1 module, supports USBUART and IIC, has sound and data transmission functions, and complies with Bluetooth 1Version 1 and passed the FCC ETST certification.
1.2 sensor modules
The solution uses sensor monitoring technology that combines MEMS sensors and FBG sensors. EMS sensor is a new type of sensor manufactured by microelectronics and micromachining technology, which integrates microelectronics and precision machining technology to realize the integration of microelectronics and mechanical systems, with small volume and energy consumption, and can realize many new functions, which is convenient for mass production and high-precision production, low cost per piece, and easy to form large-scale and multi-functional arrays. The sensing signal of the fiber Bragg grating sensor is wavelength modulated, and the measurement signal is not affected by the fluctuation of the light source, the bending loss of the fiber, etc., which is ideal for real-time vital signs monitoring systems.
According to the characteristics of the two sensors, a fiber grating sensor is installed on the back of the driver's seat to monitor the driver's vital signs in real time. MEMS sensors are installed on the central steering wheel and chassis of the car to monitor the driving status of the car and provide timely feedback. It can be said that the module provides comprehensive protection for the driver and the vehicle, which greatly increases the safety of driving.
1.3. Speech recognition module
The recognition system itself is composed of two parts: training and recognition: training is the process of modeling, analyzing the speech feature parameters in advance, making a speech template and storing it in the speech parameter library, and the recognition process is to compare the obtained voice parameters with the known parameter templates in the library through processing, and use the judgment method to find the template closest to the speech features, and the recognition results can be obtained. This process is carried out by a microcomputer fixed in the on-board terminal, which stores a voice database and can process the sound signal.
In view of the fact that the voice recognition technology is not mature enough, and the driving environment is complex, this module is mostly used for the driver's non-driving operation of the car, which not only makes the driving more intelligent and efficient, but also greatly reduces the impact of the non-driving operation on the driver, so that the driver can devote himself more fully to driving, which greatly avoids the occurrence of safety accidents.
1.4. Signal switching module
The module is completely realized by the signal transmission between Bluetooth, vehicle terminal and mobile phone, by pressing the control button on the Bluetooth headset, Bluetooth will send the request to disconnect to the vehicle terminal, the vehicle terminal disconnects from the connection with the Bluetooth headset after receiving the signal, and the internal intelligent connection system controls the driver's mobile phone and the Bluetooth headset to establish a connection, and the driver can realize the voice control of the mobile phone at this time. This module is completely virtualized and digitalized, reflecting the direction of digital development of future driving operations.
This approach is modular. The fiber grating sensor arranged on the back of the car seat monitors the driver's physical condition in real time, and the MEMS sensor arranged in the central control steering wheel and chassis of the car monitors the driving condition of the car in real time. The driver processes information through the in-car Bluetooth headset and human-computer interaction system, and implements voice control of the car.
2.1 Driver signs and vehicle driving monitoring
Through the fiber grating sensor installed on the back of the seat, the on-board system can monitor the driver's breathing, blood flow, heartbeat and other vital signs in real time during driving, when the driver reaches the critical monitoring threshold during driving, the on-board system will remind the driver through the car audio voice prompt + seat vibration that there is a problem with vital signs, and the driver needs to stop and rest. If there is no brake at this time, the on-board system automatically applies the brakes to the car until the driver's vital signs return to normal. Through the MEMS sensor installed in the central control steering wheel and chassis of the car, the on-board system can monitor the driving condition of the car, and when the car is abnormal in the driving process, the sensor will quickly transmit the information to the on-board system, and alarm through the display screen. By storing error countermeasures in the system database, the driver is provided with several suggestions on the display at the same time, and the driver can handle the feedback on his own.
2.2 Bluetooth voice intelligent control
Through the Bluetooth headset, the driver can establish a wireless connection with the on-board system, and start the voice recognition module at the same time, so as to replace the traditional manual control through voice commands, and realize non-driving operations such as switching on and off air conditioning, switching, and opening and closing window ceilings, so as to ensure that the driver sits on the seat and only needs to speak to the phone, and voice instructions are issued as needed, so that the voice control of the system can be realized, and the driver's attention can still concentrate on driving, improve the driving pleasure and ensure safety.
2.3. Wireless answering of incoming calls
The scheme through the signal switching module, so that through the Bluetooth to answer the call and voice control the on-board system can coexist, when there is **, the driver by pressing the control button on the Bluetooth headset, to carry out the signal switching of mobile devices such as the vehicle terminal and mobile phone, you can wirelessly answer **, avoid the trouble of holding a mobile phone in one hand when the traditional answering **. When the driver hangs up, the driver can choose to press the control button again to restore the signal connection with the on-board terminal, or keep the signal connection with the mobile phone and voice control the mobile phone through the Siri system.
2.4 Additional features
2.4.1. Vehicle self-locking and anti-theft function
This function realizes that after the driver carrying the Bluetooth headset leaves the car for a certain distance, the vehicle terminal can not receive the Bluetooth signal, and the vehicle will lock by itself to avoid forgetting to close the lock, so as to effectively prevent theft.
2.4.2 Vehicle location monitoring
The function is based on the combination of on-board GPS system, Bluetooth signal transmission and its cloud synchronization APP, the driver can check the location of the car and the distance between the car and the person through the supporting APP on the mobile phone, which is convenient for the driver to find his car in the sea of cars.
2.4.3. One-click for help
The function is interconnected with the 120 distress system under the premise that the owner can press the distress button on the Bluetooth headset in the event of an accident or untimely accident in the vehicle or person, and the on-board system will send a distress call to the 120 emergency center after receiving the Bluetooth signal.
Source: Science and Technology Innovation Herald.
Original title: Modular smart car Bluetooth voice control and safety assurance system.
Author: Shen Luxin, Zhou Jiantao.