Safe Joint Mechanism Based on Passive Collision Adaptation Method

 Inventors: Omid Zebardast - Dr Hadi Moradi

Abstract:

This invention is in the field of increasing the safety of all kinds of arm robots or other devices in similar conditions in dynamic and static collisions, which has particular importance in the confrontation between humans and robots. Dynamic collision, due to the high speed of the collision, mechanisms based on active adaptation are dangerous and sometimes lead to severe injuries and even death. In this design, a safe and reliable collision mechanism is presented based on the passive adaptation method, using mechanical elements. In this design, as long as the external force applied to the mechanism is less than a certain threshold and if the mechanism has enough strength to resist the force, and if the force exceeds the threshold, the mechanism will react appropriately and eliminate the effect of the additional force in the collision. The safe joint is designed based on the passive adaptation method using a linear spring and an inclined surface, the  designed safe joint is very suitable in terms of dimensions and weight, and its manufacturing cost is very low. Also, due to the 360 degrees of the joint and by using the position coder, we can detect the position of the arm after the collision, and the arm will continue to work without interruption and without the need for calibration. Another advantage is the lack of complex and accurate sensors and the quick response of the proposed mechanism. Finally, to validate the model, collision tests were performed on the designed sample.