In this paper, the virtual holonomic constraint approach is initiatively applied for the trajectory planning and control design of a typical double link underactuated mechanical system, called the Pendubot. | SCIENCE & TECHNOLOGY DEVELOPMENT, , - 2015 Pendubot trajectory planning and control using virtual holonomic constraint approach Cao Van Kien Ho Pham Huy Anh Ho Chi Minh city University of Technology, VNU-HCM, Vietnam (Manuscript Received on July 15, 2015, Manuscript Revised August 30, 2015) ABSTRACT In this paper, the virtual holonomic constraint approach is initiatively applied for the trajectory planning and control design of a typical double link underactuated mechanical system, called the Pendubot. The goal is to create synchronous oscillations of both links. After modeling the system using Euler-Lagrangian equations of motion, the parameters of the model are identified with optimization techniques. Using this model, the trajectory planning is done via Virtual Holonomic Constraint approach on the basis of re-parameterization of the motion according to geometrical relations among the generalized coordinates of the system. Keywords: pendubot, trajectory planning and control, virtual holonomic constraint approach, 2-DOF underactuated system. 1. INTRODUCTION The problem of trajectory planning and control of underactuated mechanical systems have attracted vast interest during last decades [1]. This underactuation can increase the performance of these systems in terms of dexterity and energy efficiency and also lowers the weight of the system as well as manufacturing costs. There are many instances of applications of underactuated mechanical systems in real life. Underwater vehicles, water machines, helicopters, mobile robots and underactuated robot arms are some examples of engineering applications of underactuated robotics. in both fully actuated and underactuated manipulators. However, in case of fully actuated manipulators, with considering the dynamical constraints regarding velocity and acceleration, any timing along the defined path can be achieved. But in case of robotic manipulators with passive degrees of freedom, due to existence .
