Modeling and simulation of contact and friction forces in flexible robotic arms

Articles in Press

Document Type : Original Article

Authors

• Mohammad Ehsan Yousefzadeh Kouhbanani
• Ali Mohamad Shafei

Department of Mechanical Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

10.22067/jacsm.2024.88007.1256

Abstract

In this article, multiple collisions for two-dimensional (planar) open-loop robotic systems, which are formed by n elastic links with rotational joints, have been studied.The dynamic motion equations of this system have been done by the Gibbs-Appell recursive algorithm and modeling the impact-contact phenomenon by regulized method. Timoshenko's beam theory has been used to model transverse vibrations of links. Also, to increase the accuracy of modeling, the effects of structural damping and air damping have been considered.The joints are without backlash and friction, but the friction force is included in the place where the links meet the ground. The movement of the system has two phases: flight and collision.The differential equations of the system in the collision stage include terms caused by viscoelastic forces, which result in new equations of motion. These new differential equations are very difficult due to the nature of the collision force, and solving them in a very short collision time requires special measures.Due to the very short time of collision, accurate detection of the moment of collision is very important. For this purpose, entry into the collision phase and exit from it is controlled with a very high precision with the special calculation algorithm presented in this article.To show the efficiency and accuracy of the developed program, computer simulations have been performed to study the dynamic behavior of a three-link robotic system.

Keywords

• Mode shape
• Gibbs-Appell
• friction
• elastic robot
• contact force

Main Subjects

• Robotics

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