A RATIONAL APPROACH TO REMOTE HANDLING EQUIPMENT CONTROL SYSTEM DESIGN

摘要

The approach to the design of remote handling control systems for JET (Joint EuropeanrnTorus) has undergone a metamorphosis in recent years. The original concept of specifyingrnfunctional requirements and tendering external companies without specifying the hardware andrnsoftware that was permitted, resulted in a myriad of solutions which, although functionallyrncorrect, presented JET with a number of unforeseen problems:rn1. In-house engineers had to become familiar with a wide variety of hardware and software.rn2. Operators were presented with many different computer interfaces, which had a differentrnlook-and-feel, with the robots sometimes behaving in a contradictory manner (e.g. positivernrotation being clockwise on one robotic transporter and anti-clockwise on another).rn3. Developments and fixes to the control systems usually needed long lead times and werernsometimes impossible or prohibitively expensive.rn4. A large selection of hardware spares was needed to provide cover for all the systems.rn5. Support for obsolete hardware and software was increasingly difficult.rnThe breakthrough came from the recognition that, although the remote handling equipmentrnwas specifically for and unique to JET, at a low level, the controls required were similar tornindustrial applications. Thus, widely available commercial products could be configured tornhandle the highly critical motion control, and implemented in a quite uniform control systemrnframework. The high level control software, oriented about the objects and tasks involved, wasrndeveloped in-house. At this level, the robotic systems have much in common, and a lot of thernsoftware modules could be shared or re-used.