Hydro-Québec's research institute uses portable robots to carry out maintenance operations for hydroelectric turbines. One of the most commonly used processes is robotic grinding to repair damaged surfaces. The grinding wheels used for grinding are cup wheel. Grinding with a constant angle, in forward and backward direction, generates a random profile of the grinding wheel. The uncut chip changes and control of material removal rate becomes difficult, hence the idea of creating a spherical profile of the grinding wheel. With this profile, the cutting surface becomes constant and independent of the grinding angle. The project's main objective is to develop a new method to create and maintain a spherical profile of the cup wheel.
Mathematical equations are developed to calculate the grinding angles as a function of the grinding wheel wear. An oscillating function is used to control the profile of the grinding wheel. The control of the material removal and the grinder wear is respectively insured with the models of the material removal rate and the wear rate of the cup wheel.
Several grinding tests are made to validate the models of the material removal rate, the wear rate and the oscillation. For the models of material removal rate and wear rate, the correlation coefficient is of the order of 0.73. The grinding with the oscillation model gave good results. Indeed, the spherical shape of the profile of the grinding wheel is maintained and the radius of the profile varies with an error of 4%.
| Date | 11 Sept 2017 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Zhaoheng Liu (Supervisor) & Bruce Hazel (Co-supervisor) |
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Ben Tanfous, O. (Author),
Liu (Supervisor) & Hazel (Co-supervisor),
11 Sept 2017Student thesis: Master's thesis › Master in Engineering: Mechanical Engineering