Simulation and optimization of variable stiffness flexible fingers
Compared with traditional rigid grippers,mechanical fingers used by flexible grippers are made of lightweight and soft materials,with flexible contact and strong adaptability,and can be used to grasp fragile objects with complex contours and shapes.We design and fabricate a flexible mechanical finger with stiffness-tunable property in this study.Flexible fingers consist of an internal curved actuator and an external variable stiffness jacket that works under pneumatic pressure.The pneumatic bending brake parameters were optimized using the finite element analysis method.The representative volume element(RVE)method was then used to establish an analysis method for the fiber medium clogging phenomenon in the variable stiffness jacket.Finally,combined with the stiffness-adjustable jacket,we demonstrated the variable stiffness ability of the flexible fingers.Additionally,three identical flexible fingers were assembled into a flexible claw.The result reveals that the variable stiffness jacket increased the claw gripping force by more than twice.Moreover,the proposed flexible fingers have great application potential in the field of flexible robots.
flexible fingersbending deformationvariable stiffnessfinite element analysisoptimized design