Manned Lunar Rover Failure Mode And Driving Strategy Research

Manned lunar rover as an important vehicle in our country manned lunar exploration program, is an essential equipment for astronaut walk on the moon and lunar soil process. Manned lunar rover always use drive-by-wire four wheel hub motors as drive mode. The way not only reduced the size and the weight of the entire transmission system, but also improved the efficiency of the drive; the most important is easy to implement vehicle suspension and body folds, through the flexible cable connection of each drive motor integration within the wheel. But, using four wheel motor as power source, increased the failure rate of manned lunar rover driving system. Astronaut driving manned lunar rover far away from the lander, walking in unknown and complex surface, If one or more motor fails, will reduce the vehicle driving performance and traffic ability, and will have a significant impact for the astronauts safety. Hence, the research of how can the manned lunar rover help astronauts returned to lander successfully is of great significance.The main content of the article includes the following several aspects:First of all, the article studied the fault types of Brushless DC Motor, and the causes and consequences of different faults. It Established Engine condition monitoring and fault diagnosis system based on signal processing, for common winding short-circuit fault?winding open circuit failure?the stator temperature fault?bearing fault?the controller for the thermal?the controller excessive current?the controller under-voltage fault of Brushless DC Motor. The system uses six sensors to monitor and collect motor three-phase winding current signal?bearing vibration signal?controller and the stator temperature signal, realized the condition detection and fault diagnosis of Brushless DC Motor.Second, this article defined and divided failure mode of manned lunar rover traction drive system. It can be divided into fatal failure and severe failure according to the motor fault is reversible or irreversible. It formed 80 kinds of fault modes, combined the location of the fault wheels and wheel failure number of manned lunar rover. This project established the dynamic model of differential sideslip steering Manned lunar rover for the straight drive?turning drive?climbing and going through obstacle on the plat moon's surface. It analyzed the influence of different failure modes for the performance of straight drive?turning drive?climbing and going through obstacle by ADAMS simulation software, to lay the theory foundation for manned lunar rover return to lander in different failure modes.Finally, this project make a research in view of manned lunar rover can be return to lander safely or not in fatal failure modes. Combined with the feature of the moon's surface, it set up a road for manned lunar rover return to lander in failure modes. The road constituted by Flat surface, 5 ° slope and 80 mm steps. It analyzes the three factors restricting manned lunar rover and astronauts return to lander in the above conditions. That is includes manned lunar rover could be overcome slope and obstacles or not in failure mode, and can return to the lander or not in the suit work within the time limit. It also put forward the driving strategy of the way return to the lander, when the single motor fatal malfunction?two motor fatal malfunction and three motor fatal malfunction happened in manned lunar rover. This strategy make manned lunar rover return to the lander safely in the single motor fatal malfunction mode?two motor fatal malfunction mode and three motor fatal malfunction mode.