Research On Autonomous Take-off, Landing And Flight Safety Of UAV

The structure of pneumatic of micro four rotor unmanned aerial vehicle (MAV) is simple and the cost of MAV also is low, so it has already been used in the industrial field extensively, for example military reconnaissance, border inspection, industrial equipment inspection and so on. Especially it is very appropriate to be applied in the inspection of power tower and overhead line. In the past, the power company needed to use the traditional helicopter which is steered by human to complete the inspection task. But there are many disadvantages in the inspection, the most important weakness are the high cost and the use of strict condition because of limited by the natural environment, meanwhile the efficiency of inspection is very low. The MAV overcomes these disadvantages coming from traditional helicopter, and improves the efficiency of inspection greatly and decrease the cost. So the MAV has already been more and more used in the inspection of power equipment and became a research focus.This paper researches the application of MAV in the inspector of power equipment (tower, overhead line and insulator) and creates an approach which controls the MAV complete an entire inspection process without human’s control meanwhile the process which is security includes take-off, landing and security flying automatically. The paper model the MAV to get a mathematic model, and improve the PID algorithm of MAV. The PID is designed as two-stage controller which includes two-stage feedback of a linear velocity and acceleration and angle velocity and acceleration that promotes the steady of controller. And the paper finishes the design of take-off and landing function based on the PID controller.The MAV is very easy to be disturbed by gust because it’s size is small and it’s weigh is low, and the MAV also is easy to collide with the power tower or overhead line because the error of sensor. So the paper creates an approach to avoid the collision between the MAV and tower. At first the linear fitting method is used to fit a curve of power tower distribution, after that the paper use a kind of security distance function which is created by this paper to move the curve according to a distance value calculated by the function, so a zone is called no-fly zone is created. Second the paper creates a gust function to evaluate the influence of gust on the MAV. The function can calculate a value which is used to decide whether gust disturb the MAV when the MAV inspects the equipment. Finally we associate the gust function and artificial potential method to plan the inspection path, which can guarantee that the MAV never fly into the no-fly zone so the MAV never collide with the equipment.The paper designs the control software and make a MAV platform to finish the take-off, landing and the security flying approach.