Latest Papers

ASME Journal of Mechanisms and Robotics

  • Measurement Configuration Optimization and Kinematic Calibration of a Parallel Robot
    by Huang C, Xie F, Liu X, et al. on December 10, 2021 at 12:00 am

    AbstractThis paper presents the kinematic calibration of a four-degrees-of-freedom (4DOF) high-speed parallel robot. In order to improve the calibration effect by decreasing the influence of the unobservable disturbance variables introduced by error measurement, a measurement configuration optimization method is proposed. Configurations are iteratively selected inside the workspace by a searching algorithm, then the selection results are evaluated through an index associated with the condition number of the identification Jacobian matrix; finally, the number of optimized configurations is determined. Since the selection algorithm has been shown to be sensitive to local minima, a meta-heuristic method has been applied to decrease this sensibility. To verify the effectiveness of the algorithm and kinematic calibration, computation validations, pose error estimations, and experiments are performed. The results show that the identification accuracy and calibration effect can be significantly improved by using the optimized configurations.

Data-Driven Analysis of Locomotion for a Class of Articulated Mobile Robots

Abstract

In the recent past, the use of autonomous vehicles is becoming of relevant interest in several fields of application. In many cases, the use of articulated structures is preferred to single chassis robots for their peculiar modularity. Such vehicles are often built as an active front module and a rear one that is pulled passively or that can contribute to the vehicle traction when required. Understanding whether this contribution is convenient or not is the main matter of this paper. Two different mobile robots of different scales and purposes are taken into consideration. A dynamic model is presented and analyzed. An experimental validation of the model parameters is also presented in order to make it exploitable as a reliable analysis tool. At last, a simple yet effective actuation law is tested for both the considered robots to evaluate whether the contribution of the back module is beneficial or not to the whole machine maneuverability.
Read More
Journal of Mechanisms and Robotics Open Issues