A three-dimensional constrained artificial potential field method was proposed for planning of real-time obstacle avoidance trajectory for the missile-borne air vehicle

due to the low altitude and needing real-time obstacle avoidance. Combined with a potential field—height adjust potential field and the dynamic constraints of the missile-borne air vehicle

the artificial potential field method was extended to three-dimensional space. The new method not only inherited the advantages of fast calculation and less memory

but also could ensure the flight performance of planning trajectory for the missile-borne air vehicle. The simulation results show that the constrained artificial field method has the following advantages compared with the traditional artificial potential field method: the planning trajectory presents flight performance; the swing phenomenon near the obstacle is significantly reduced; the oscillatory phenomenon in narrow passage is significantly improved; it is easier to escape from the local minimum point.