Department of Mechanical Engineering, National Chung Hsing University, No. 145, Xingda Road, South District, Taichung City 40227, Taiwan.
Department of Electrical Engineering, National Taiwan Normal University, No 162, Section 1, Heping East Road, Taipeu City 106, Taiwan.
Sensors (Basel). 2019 Mar 25;19(6):1459. doi: 10.3390/s19061459.
A vision-based three degree-of-freedom translational parallel manipulator (TPM) was developed. The developed TPM has the following characteristics. First, the TPM is driven by three rodless pneumatic actuators and is designed as a horizontal structure to enlarge its horizontal working space to cover a conveyor. Then, a robot-vision system (including a webcam mounted on the TPM) collects images of objects on the conveyor and transfers them through the LabVIEW application programming interface for image processing. Since it is very difficult to achieve precise position control of the TPM due to the nonlinear couplings among the robot axes, feedback linearization is utilized to design an adaptive interval type-2 fuzzy controller with self-tuning fuzzy sliding-mode compensation (AIT2FC-STFSMC) for each rodless pneumatic actuator to attenuate nonlinearities, function approximation errors, and external disturbances. Finally, experiments proved that the vision-based three degree-of-freedom TPM was capable of accurately tracking desired trajectories and precisely executing pick-and-place movement in real time.
研制了一种基于视觉的三自由度平移并联机器人(TPM)。所开发的 TPM 具有以下特点。首先,TPM 由三个无杆气动执行器驱动,并设计为水平结构,以扩大其水平工作空间,覆盖输送机。然后,机器人视觉系统(包括安装在 TPM 上的网络摄像头)采集传送带上物体的图像,并通过 LabVIEW 应用程序编程接口传输图像以进行图像处理。由于机器人轴之间的非线性耦合,很难实现 TPM 的精确位置控制,因此利用反馈线性化设计了自适应区间型 2 模糊控制器(AIT2FC-STFSMC),为每个无杆气动执行器设计自适应区间型 2 模糊控制器(AIT2FC-STFSMC),以衰减非线性、函数逼近误差和外部干扰。最后,实验证明基于视觉的三自由度 TPM 能够精确跟踪期望轨迹,并实时精确执行取放运动。