Abstract: In extraterrestrial detection, multi sensor data synchronous acquisition is necessary. A novel multi sensor hardware time synchronization method without GPS (global positioning system) is proposed to solve the problem that the GPS signal cannot be achieved in extraterrestrial detection. The embedded MCU (micro control unit) is employed as the core of hardware system, so that a high precision synchronous acquisition can be realized. A method combining simulated GPS time service, PPS (pulse per second) clock correction and pulse trigger from MCU is employed to get the time synchronization between multi camera IMU (inertial measurement unit) and LIDAR. Finally, a hardware platform is established in an explorer and some new proof schemes are designed. The experimental results validate the effectiveness of the proposed method. The synchronous precision is about 2 ms, which is significantly improved compared with the existing extraterrestrial detector. This method can be used as a reference for the data acquisition, autonomous navigation and obstacle avoidance of the next generation of extraterrestrial detector.

Key words: multi sensor, time synchronization, extraterrestrial detection, hardware trigger, micro control unit