機械手臂控制器之可程式系統晶片設計與實現

Design and Implementation of a Controller for Robotic Manipulator Using SOPC

林穎宏(Ying-Hong Lin) ； 蔡政哲(Zheng-Zhe Cai)

《科學與工程技術期刊》 6卷4期 (2010/12) Pp. 19-26

https://doi.org/10.7117/JSET.201012.0019

摘要

本文應用可程式系統晶片(system on programmable chip, SOPC)技術設計與實現一機械手臂控制器以控制機械手臂夾取空間中物體至定點，控制器控制之裝置包括一六軸機械手臂以執行夾物動作、兩組CCD(charge coupled device)模組以擷取物體影像進而判定物體空間座標值。控制器採用ALTERA公司的Cyclone Ⅱ FPGA實現，其中包括：(1)NIOS Ⅱ軟核處理器與自定義之PWM訊號產生周邊：NIOS Ⅱ用以執行物體空間座標定位、物體空間座標值轉爲機械手臂中伺服馬達之轉動角度的D-H演算法，此後將轉動角度送至自定義之PWM訊號產生周邊以產生PWM訊號驅動機械手臂。(2)CCD控制模組：此模組使用硬體描述語言設計，控制CCD進行影像擷取，並將擷取之影像轉換爲灰階存至FPGA外的SDRAM中以供NIOS Ⅱ取用。所實現之控制器經實體測試可達控制機械手臂夾物至定點功能。

關鍵字

FPGA ； 可程式系統晶片SOPC ； 機械手臂控制器 ； 影像擷取

並列摘要

This paper presents the design and implementation of a controller using the system on programmable chip (SOPC) technology for controlling a robotic manipulator to fetch an object in space to a fixed position. The controlled devices for this controller include a six-axis robotic manipulator to perform fetching tasks, and two CCD modules for capturing images of the object to determine its coordinates in space. The controller was implemented in an Altera CYCLONE Ⅱ FPGA that includes: (1) a NIOS Ⅱ soft processor and customized PWM signal generation peripherals (the NIOS Ⅱ is used to execute programs for locating coordinates of an object in space, performing a D-H algorithm that transforms coordinates to rotating angles for six servos on the robotic manipulator and, moreover, delivering the rotating angles to customized PWM signal generation peripherals to generate PWM waves for driving the robotic manipulator; (2) a CCD control module, designed by the hardware description language (HDL), which is used for controlling processes of image capturing, turning the captured images into grayscale, and saving the images into SDRAM outside of FPGA (which also allows NIOS Ⅱ to gain access). Field tests on the controller achieved the expected function of controlling the robotic manipulator to fetch an object in space to a fixed position.

並列關鍵字

FPGA ； SOPC ； robotic manipulator controller ； image capture