Kinematic Optimization for the Design of a Collaborative Robot End-Effector for Tele-Echography

Abstract

Tele-examination based on robotic technologies is a promising solution to solve the current worsening shortage of physicians. Echocardiography is among the examinations that would benefit more from robotic solutions. However, most of the state-of-the-art solutions are based on the development of specific robotic arms, instead of exploiting COTS (commercial-off-the-shelf) arms to reduce costs and make such systems affordable. In this paper, we address this problem by studying the design of an end-effector for tele-echography to be mounted on two popular and low-cost collaborative robots, i.e., the Universal Robot UR5, and the Franka Emika Panda. In the case of the UR5 robot, we investigate the possibility of adding a seventh rotational degree of freedom. The design is obtained by kinematic optimization, in which a manipulability measure is an objective function. The optimization domain includes the position of the patient with regards to the robot base and the pose of the end-effector frame. Constraints include the full coverage of the examination area, the possibility to orient the probe correctly, have the base of the robot far enough from the patient’s head, and a suitable distance from singularities. The results show that adding a degree of freedom improves manipulability by 65% and that adding a custom-designed actuated joint is better than adopting a native seven-degrees-freedom robot.

HCDR-based motion planning for mobile manipulators with the continuous trajectory task

“…In the trajectory planning, M 3 + 1 path points of the end effector are taken according to the target motion trajectory, then M 3 sub-trajectories for each joint can be generated based on the IK model. From the reference report, 35 the modified cubic spline functions of the angular displacement for each joint when t 2 ½t 0 , t 1 and t 2 ½t lÀ1 , t l can be written as equation (19).…”

“…The desired continuous trajectory of the end effector always can described by, F(x, y, z) = 0, G(x, y, z) = 0. Since joint angles are represented by time-varying functions as equation (19), the actual trajectory points of the end effector can be obtained relevant to the time based on forward kinematics of the manipulator. Therefore, this section presented a method to take points from the desired trajectory and calculate the positional error, aiming to truly reflect the deviation between the desired and the actual trajectories.…”

“…In summary, motion performance indexes were not fully considered in existing studies, like safety, 16 stability, 17, 18 manipulability, 19 motion accuracy, 20, 21 and efficiency, 22 etc. But with the continuous development of high-end manufacturing field, the overall motion performance of the robot become critical, for example, continuous trajectory tasks of large structures.…”

A review on tele-manipulators for remote diagnostic procedures and surgery

“…The remote robotic ultrasound system proposed by Huang et al [ 51 ] for 3D scanning of human tissues used the ProSix C4 robot by Epson [ 52 ]. UR5 collaborative robot arm by Universal Robots Corporation, Denmark, has been one of the most widely used commercially available robot manipulators because of its low cost and compliance with ISO 10218-1:2006 [ 53 ]. Mathiassen et al [ 24 ] used the 6DOF UR5 system to interact with the patient and the Phantom Omni system as the remote controller.…”

Kinematic Optimization of 6DOF Serial Robot Arms by Bio-Inspired Algorithms

“…Different robot design methodologies have been proposed using the combination of optimization algorithms and performance indices as objective functions. Some of them report algorithms such as MultiStart to optimize manipulability index [2], minimization of dexterity index [3], and exhaustive method to optimize volume, workspace, dexterity, and static efficiency [4]. Robot design proposals based on bio-inspired algorithms like particle swarm optimization (PSO) have been reported in the literature.…”