IJCAS

Although visual servoing has been considered as a solution to increase dexterity and intelligence of the robotic systems specially in unstructured environments, some prominent deficiencies are preventing it from practical employment. Trajectory planning is a solution to overcome the shortcomings of visual servoing and makes it practical for industrial applications. In this paper, a new trajectory planning technique is developed to perform image-based visual servoing (IBVS) tasks for a 4 DOFs robotic manipulator system. In this method, the camera’s velocity screw is parameterized using time-based profiles. The parameters of the velocity profile are then determined such that the velocity profile takes the robot to its desired position. This is done by minimizing the errors between the initial and desired features. A depth estimation technique is proposed to provide the trajectory planning algorithm with an accurate initial depth. This algorithm is tested and validated via the experiment on a 4 DOFs Denso robot in an eye-in-hand configuration. Experimental results demonstrate that the proposed method provides with a reliable visual servoing algorithm by overcoming the IBVS drawbacks such as surpassing the system limits and causing instability of the system in fulfilling the tasks which require a 180o rotation of the camera about its center."

Keywords: Optimization, robotics, trajectory planning, visual Servoing.