Soft Control Research Cell Injection System

In cell injection process, the injection pipette has two moving spaces. In free space, the injection pipette does not interact with the cell, in this case, only the position control of the injection pipette is needed; in contact space, the injection pipette interacts with the cell, in this case, not only the position control of the injection pipette is needed, but also the need for controlling the injection pipette-cell interaction force. Trajectory tracking control and force tracking control of the injection pipette in cell injection are studied in this paper. Firstly, for the cell injection system modeling errors, in order to improve the ability of the pipette trajectory tracking control, robust controller is introduced.The cell injection force is a time-varying force, particularly when the cell injection system model and the cell membrane stiffness exist uncertainties, the conventional impedance control policy does not meet the precise tracking control of the time-varying injection force. Therefore, on the basis of the traditional impedance control method, based on adaptive impedance control force tracking control strategy is proposed in this paper, and designed an adaptive impedance force controller. The controller does not require accurate knowledge of the environment, and get a certain amount of self-adaptability for tracking time-varying force.Finally, further research has been on traditional impedance control method, which is to analyze the root causes of poor time-varying force tacking control of traditional impedance. An improvement is made about the traditional position-based impedance control in order to realize time-varying force tracking. At the same time, the online identification of the two parameters of the environment stiffness and real-time injection force is accomplished, so that the system has a strong adaptability to the changes of the characteristics of the environment stiffness and disturbance. Through the research and analysis of simulation experiments, the improved impedance controller is able to track any time continuous force reference signal to achieve compliance control.