Design of a new driving safety system for large road transport vehicles

Abstract: This paper analyzes the blind spots of large vehicles and the single function of the solution in detail. It is found that the traditional department-standard machine meets the supervision needs but has a poor interactive experience. Drivers have a certain rejection mentality and deliberately block and destroy the satellite positioning terminal to evade monitoring, indicating that the overall online rate of department-standard machines is not high. This paper proposes a new driving safety system that can connect up to 8 channels of video, integrates a 360-degree panoramic algorithm to solve the problem of vehicle visual blind spots , supports reversing display, and provides recording and local playback functions. It has a 4G full network system that supports online maps, facilitates navigation and viewing real-time road conditions, integrates ADAS and DMS that meet regulatory requirements, supports JT/T808 and JT/T1078 standard protocols, and realizes remote supervision. The system not only meets the various needs of drivers, but also meets the regulatory requirements of traffic management departments. It has high integration, rich functions, and can complete functions that require multiple devices to complete. It is economical and practical, which helps to resolve the contradiction between drivers and regulatory agencies and reduce the rate of traffic accidents.

About the author: Sun Desheng (1980-), male, master, engineer, currently engaged in the design and development of embedded systems, intelligent electronic products, and automotive electronic appliances. E-mail: 89660958@qq.com.

0 Preface

As China's economy continues to grow at a high speed, large vehicles are increasing rapidly, including large trucks, buses, and public transportation. These vehicles have some common characteristics, such as large size, high body, large turning radius, large inner wheel difference, and many blind spots when driving [1-2]. In recent years, there have been more and more traffic accidents caused by the blind spot problem of large vehicles . Therefore, it is particularly important to solve the blind spot problem of large vehicles [3]. There are also some devices on the market that solve the driving blind spot problem separately, such as electronic exterior rearview mirrors and 360 panoramic views, but their functions are single, the integration is low, and the scalability is poor. In addition, for regulatory needs, the Ministry of Transport requires road transport vehicles to be equipped with equipment that meets the JT/T808 and JT/T1078 standards. Two passenger and one dangerous goods vehicles must also support active safety ADAS, etc. The structure tends to be a single-spindle machine, which is commonly known as a departmental standard machine on the market. It generally does not have a display screen, the driver cannot directly operate the device, lacks an interactive experience, and cannot play back videos locally, which is very inconvenient. Department-standard aircraft are more focused on technical supervision. Drivers have a certain aversion to them and often deliberately block or damage satellite positioning terminals and evade monitoring. As a result, the online rate of department-standard aircraft is not high, and monitoring personnel have a weak sense of responsibility. They are unable to remind and correct drivers' illegal and irregular behaviors in real time, which also makes supervision difficult [4].

This paper proposes a new driving safety system based on Qualcomm MSM8953, which supports up to 8-channel video access, imports 360 panoramic algorithm to solve the visual blind spot of the vehicle, is equipped with a 12.3-inch (1 inch = 2.54 cm) high-definition display screen, has a clear display effect, supports reversing display, and provides DVR recording function. In case of emergency, the local machine can quickly play back the video. The system with 4G full network access can support online maps, convenient navigation and view real-time road conditions. It supports ADAS and DMS that meet the active safety requirements of supervision , as well as JT/T808 and JT/T1078 standard protocols, and can easily realize platform supervision. This system design solves the driver's blind spot problem, meets the needs of reversing safety, viewing live navigation, and local playback of multi-channel video recordings, and supports JT/T808 and JT/T1078 standard protocols and active safety ADAS and DMS to meet regulatory needs. The equipment has a high degree of integration and can complete functions that require multiple devices. It is economical and practical, can balance the contradictions between drivers and regulators, and truly use technology to reduce traffic accident rates, benefiting the country and the people.

1 Hardware design of new driving safety system

This paper proposes a set of intelligent systems designed based on the Qualcomm 8953 platform that are rich in functions and meet the safe driving requirements of large road transport vehicles.

1.1 System Hardware Framework Design

The hardware block diagram of the new intelligent driving safety system is shown in Figure 1.

The system main controller uses Qualcomm MSM8953, 8-core Cortex-A53, main frequency 2.0 GHz, 14 nm process, GPU is Adreno506, integrated 4G LTE baseband supports LTE CAT 7 full network access, and can be connected to the Internet by inserting a SIM card. The power module adopts a wide voltage design, and can work normally at 9 to 36 V, adapting to vehicles with standard voltages of 12 V or 24 V. The system has an operating temperature of -30 to 75°C and a storage temperature range of (-40 to 85)°C. The system uses SKhynix's H9TQ27ADFTMC eMCP, which has 32 GB of storage and 3 GB of LPDDR3 running memory. It is equipped with a 12.3-inch 1 920×720 resolution TFT LCD display and a 12.3-inch 10-channel touch screen. The built-in GNSS module supports Beidou, GPS, GLONASS and other positioning systems, and the built-in wireless module supports 802.11 b/g/n/ac functions. The system supports 5 hard buttons, which can be used for power on/off, volume adjustment, or defined as other shortcut operations. The hand microphone supports PTT intercom and playback functions, and can communicate with the background control center in real time. The system supports access to multiple cameras, AHD signals, and can access up to 8 720P cameras, which can solve driver blind spots, AI intelligent recognition, etc., and supports DVR recording and storage to TF card or USB disk. The system reserves two sets of serial ports, one set can be connected to the CAN module to obtain the original vehicle CAN information, and the other set can be connected to the radar host to obtain surrounding obstacle perception, which expands the function of the entire system and improves the practicality of complex scenarios.

1.2 Multi-channel camera access design

The system design uses Qualcomm MSM8953, which can connect to MIPI 4 Lane CSI0 and CSI1 interfaces. The maximum processing capacity of one CSI is 4 channels of 720P@30 fps, and two CSI channels can connect to 8 channels of 720P cameras. The multi-channel camera access is shown in Figure 2.

Figure 2 Block diagram of multi-channel camera access

CSI MIPI signals support virtual channels. As shown in Figure 2, the video decoding chip TP2855 connected to the main control platform MSM8953 provides 4 Lane signals through CSIMIPI. VC0 ~ VC7 represent 8 virtual channels, each of which can be connected to 1 camera. The data of 4 cameras are fused together according to the virtual channel design through 1 video decoding chip TP2855, and then sent to the main control through MIPI 4 Lane. In the main control MSM8953, the fused data is disassembled according to the virtual channel and restored to the independent data of 4 cameras. The entire system can be connected to forward ADAS, DMS, in-car monitoring, 360 panoramic camera, and standard AHD signal 720P camera for other purposes. The system also supports video recording, including 8 cameras recording and storing them in TF card or USB flash drive at the same time. Its strong video capability is crucial to the value of the entire system.

1.3 Design of access to extended functional modules

The system hardware interface is limited. In order to expand some functions, some other mature functional modules have to be connected to enrich the system functions and improve the experience. Taking the expansion of CAN module and radar host functional module as an example, the access design is shown in Figure 3.

Figure 3 Functional module expansion block diagram

The system reserves two serial ports, one of which can be connected to the CAN module. The CAN module is connected to the vehicle CAN, and then the parsed CAN information is sent to the main control platform through the RS232 serial port, such as real-time vehicle speed, left turn, right turn, reversing, gear position and other information, which can be used for ADAS warning and intelligent switching of blind spot display images. The other serial port of the system is connected to a radar host, which can support up to 8 radar probes connected to the radar host. The radar host obtains the distance information of the obstacles ahead detected by each probe in real time, and sends it to the main control platform through the serial port protocol. The main control then determines the direction of the warning information based on the preset probe installation position. The distance information of the radar probe is used to trigger the change of the system display state. When processing other application scenarios, such as when the radar detects that there is an object blocking the close range of the right probe on the navigation page, the system can call up the camera image installed on the right side of the vehicle in real time according to the installation position of the probe [5], so that the driver can observe and make safe and reasonable operations.

2 New driving safety system software design