Field repair and construction of large hydropower equipment with a portable robot

Abstract

Field repair work on large hydropower equipment is rarely automated due to the high complexity of the task. Generally, the work is done manually or the equipment is dismantled and repaired off site at greatly added cost and time. This paper surveys work carried out with the SCOMPI robot in the field on large hydropower equipment. SCOMPI is a small, portable, multiprocess, track-based robot. This paper is the continuation of another paper in which the fundamentals of the robot technology are described in greater detail. Over the past 15 years, SCOMPIs have been extensively employed for a variety of field applications on equipment such as turbines, head gates, spillway gates, and penstocks. Initially designed to repair cavitation damage to turbines, the robots are now applied to reinforce turbines or to improve their performance in terms of efficiency. More recently, they have been used for the refurbishment of gates and for the construction of penstocks. C 2011 Wiley Periodicals, Inc.

Study and validation testing of the dynamics of a robotic system with flexible links and joints

“…It is now possible to calculate the gravitational torques ( i ) in each joint for a given position of the robot. It is then only a matter of multiplying the torque by the associated joint compliance (c i ) to find the deformation of the joint due to its flexibility using Equation (2).…”

“…In order to automate and optimize repairs to hydropower equipment such as turbines, Hydro-Québec designed a compact, lightweight robot with six degrees of freedom [1,2]. The robot, called "SCOMPI", is used for repair jobs involving material removal through grinding (see Fig.…”

Modal analysis of a light-weight robot with a rotating tool installed at the end effector

“…Vibroimpact vibrations are the primary concern when grinding with a flexible robot. 7,8 Roughly, the vibroimpact effect can be decomposed into the rotating effect of the operating grinder and the impact when the grinding wheel contacts the workpiece.…”

Robotic polishing of turbine runners

“…Robotic polishing is widely studied as shown in [2]. The compact Scompi robot [3,4], designed to access complex turbine surfaces, can replace manual polishing. New highperformance abrasives developed at 3M help achieve exceptional surface finish and good productivity.…”