Kinematic and Static Analyses of Tendon-driven Surgical Robots with Lockable Joints

With large workspace and slim body, tendon-driven surgical robots are widely studied for minimally-invasive surgery. Current research trend for tendon-driven robots includes more advanced functions such as variable stiffness and lockable joint. This paper analyzes the kinematics and statics of the tendon-driven robot with lockable joints which we proposed in our previous work. We first introduce the joint locking function of the robot, the kinematics of the robot is analyzed with three representative robot states. Then the static model of the robot which is based on Euler-Bernoulli equation is derived and validated by experiments. The experimental results show that the model has high accuracy. With this model, we can accurately predict the deformation of the robot when external force is applied.