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In the research of robotic manipulator，trajectory planning and dynamics analysis are very important.In view of the structural characteristics of the four-DOF manipulator for electro test and installation of ground wire，the dynamics model is established by Lagrange method and the dynamics analysis is carried out.On the basis of fourth order polynomial，the non-impact trajectory planning is proposed.The Simulink module in Matlab is used to get the curve of the moment and force of each joint changing with time.Using Adams software to carry out dynamics simulation，the moment and force curve of each joint are got，and compare with the curve calculated by Simulink，the correctness of dynamic analysis are confirmed，the foundation for the next structural design and system control is laid.

The emergence of regular short repetitive palindromic sequence clusters (CRISPR) and CRISPR- associated proteins 9 (Cas9) gene editing technology has greatly promoted the wide application of genetically modified pigs. Efficient single guide RNA (sgRNA) is the key to the success of gene editing using CRISPR/Cas9 technology. For large animals with a long reproductive cycle, such as pigs, it is necessary to screen out efficient sgRNA in vitro to avoid wasting time and resource costs before animal experiments. In addition, how to efficiently obtain positive gene editing monoclonal cells is a difficult problem to be solved. In this study, a rapid sgRNA screening method targeting the pig genome was established and we rapidly obtained Fah gene edited cells, laying a foundation for the subsequent production of Fah knockout pigs as human hepatocyte bioreactor. At the same time, the method of obtaining monoclonal cells using pattern microarray culture technology was explored.