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In the hydropower industry, in situ maintenance work of turbine runners to address issues such as cavitation damage and cracking is mainly performed manually. Alternatively, the entire turbine requires disassembly and is repaired off site at greater cost. This paper presents the development and fundamentals of robotic technology designed to perform work in(More)
This paper describes the approach taken by Alstom and Hydro-Quebec (HQ) in the development of robotic polishing to improve turbine efficiency by reducing surface roughness. Modern, large hydraulic turbines are profiled by a 5-axis milling machine and are polished manually. By robotizing the polishing, it becomes possible to obtain a better surface finish at(More)
Robot manipulators play an important role in industrial automation. Various aspects of robotic systems were subject of intensive investigations in the past, but the vibration problems in robotic machining processes have been rarely treated in the available literature. In this paper we present dynamic modeling of an ongoing research to study chatter(More)
This paper presents the development and implementation of a robotic technology designed to perform in-situ interventions in hydroelectric turbines. A new manipulator was designed with a unique, track-based kinematics well suited to access turbine blades in a confined space. As most work is done on curved surfaces, the robot relies on a curvilinear space(More)
This paper presents the results of a partnership between Alstom and Hydro-Québec for the development of a new factory robotic polishing process. The goal is to improve turbine efficiency by reducing surface roughness to a level that is unattainable with conventional methods. Three entire axial-flow turbines for Hydro-Québec's Sarcelle power(More)
The dynamics of a 6 DOF lightweight and compact manipulator is modeled and simulated in this work. Both joint and link flexibilities are considered in order to determine modal properties of the robotic system. The numerical results are then compared with experimental measurements of predefined trajectories through a laser tracker. It is demonstrated that(More)
This paper presents a new robotic heat treatment process designed to performed in situ interventions in hydroelectric turbine runners. Considering the down-time required to dismantle a turbine unit, most utilities perform in-situ inspections and interventions to address issues such as cavitation and cracking. Repairs are primarily done by welding. Lacking a(More)
This paper presents a robotic application for in situ repair of the seal surfaces of a large hydropower spherical valve. The repair involves laser scanning, machining, welding and polishing using the portable track-based Scompi robot. To perform the machining, the robot uses a tool guide mechanism that locates accurately the machining tool and holds it(More)
In the hydraulic business, the steel penstock liner sections involved in construction projects are typically welded manually on site. Confronted with a scheduling conflict with a critical project, Hydro-Quebec (HQ) teamed up with LAR Machinerie (LAR) to robotize the penstock welding. HQ's SCOMPI<sup>&#x00AE;</sup> portable robots were put to the task. The(More)