Development and Analysis of an Electrically Activated Sucker for Handling Workpieces With Rough and Uneven Surfaces

In this study, we designed an electrically activated sucker that can handle workpieces with rough and uneven surfaces. The new sucker uses a motor to drive its blades to form a rotational flow in a shell, generating a cupped negative pressure distribution and a resulting suction force F. Unlike in existing suckers, the rotational flow in the new sucker is formed close to the upper surface of the workpiece and extends to the outermost region of the shell. There is no air inlet or outlet in the space enclosed by the workpiece and the shell and, thus, no inlet or outlet flow is caused. This design solves the traditional problem of vacuum leak, maintains the suction force even for workpieces with rough and uneven surfaces, and works with little energy consumption. Through theoretical analysis and experiments, we studied the key parameters, i.e., the rotational speed ω and inner radius R₂ of the shell, and clarified the relationships of F-ω and F-R₂. We also investigated the effect of the driving torque, energy consumption, and surface state on the suction force. Furthermore, we used the new sucker to pick up several types of workpieces to confirm its applicability. Finally, we compared the force-energy ratio and force-area ratio of the new sucker with existing suckers and confirmed that the new sucker is superior in terms of force-energy ratio but is inferior in terms of force-area ratio.