In order to solve the problem of time optimal trajectory planning of six-degree-of-freedom citrus picking manipulator

a multi-strategy improved sparrow search algorithm (MISSA) for trajectory planning is proposed in this paper. Firstly

the kinematics model of the manipulator is established with the improved D-H parameter method

and its forward and inverse kinematics are solved

and then the joint space trajectory of the manipulator is established by 3-5-3 polynomial interpolation. Next

aiming at the ordinary sparrow algorithm

using Logistic chaotic map to homogenize the population

and combining the local and global search ability of the improved sine and cosine strategy balance algorithm

the improved sparrow search algorithm is obtained. Finally

the algorithm is used to plan the time optimal trajectory of the manipulator

and then compared with GA

PSO and SSA algorithms. The results show that the MISSA has a significant improvement in convergence speed and accuracy compared with the other three algorithms

the joint running time is reduced by 46.7%

and the joint kinematics curves are smooth and without sudden change after optimization

which verifies the effectiveness of the new algorithm.