Multi-DOF lunar sampler with double flexible rod

Considering the disadvantages of the small one-flexible-rod lunar sampler, a double-flexible-rod multi-degree-of-freedom (multi-DOF) lunar sampler is developed. First, the design of the mechanical structure is introduced. Moreover, the kinematics is built based on the mechanical structure and the D-H rules. Since the opening cylindrical shell is adopted as the sampling arm, the flexible variables are introduced into the kinematical analysis to satisfy control requirements. The experiments show that the flexible kinematical algorithm is suitable for the control of the sampler and the control accuracy is greatly improved. The maximum position error at the sampling head is 2.8 mm. The working stability and the drilling power of the sampler are also improved compared with the small one-flexible-rod lunar sampler. The maximum axial force that the flexible arm can bear is 36.4 N when the length of the flexible arm is 700 mm, which meets the requirements of working.