Abstract
Base vibrations are detrimental to the precision of high-speed robots. When a robot accelerates it induces opposing reaction forces and moments on the supporting base frame. The frame will deflect, vibrate and transmit these vibrations to the robot’s end-effector, the floor and the equipment in the surroundings.
Dynamic balancing targets these disruptive vibrations by a specific design of the moving links, such that the reaction forces and moments become constant. As a consequence, the robot will induce no, or limited, vibrations in the base frame, improving the performance of both the robot and the systems in the vicinity. Parallel mechanisms are especially suited for dynamic balance, in comparison to their serial counterparts, as they permit more simple, light-weight and economically viable solutions. However, their kinematic and dynamic models are also more complex, which impedes a straightforward solution. Moreover, current systematic approaches are either not applicable to spatial mechanisms with multiple degrees of freedom or do not yield all possible solutions.
This thesis presents three screw theory based methods to systematically determine the complete dynamic balance solution for arbitrary, nonsingular mechanisms with lower kinematic pairs. Based on these methods three novel robot designs are presented, demonstrating that the dynamic balance of spatially moving parallel robots is within reach.
Dynamic balancing targets these disruptive vibrations by a specific design of the moving links, such that the reaction forces and moments become constant. As a consequence, the robot will induce no, or limited, vibrations in the base frame, improving the performance of both the robot and the systems in the vicinity. Parallel mechanisms are especially suited for dynamic balance, in comparison to their serial counterparts, as they permit more simple, light-weight and economically viable solutions. However, their kinematic and dynamic models are also more complex, which impedes a straightforward solution. Moreover, current systematic approaches are either not applicable to spatial mechanisms with multiple degrees of freedom or do not yield all possible solutions.
This thesis presents three screw theory based methods to systematically determine the complete dynamic balance solution for arbitrary, nonsingular mechanisms with lower kinematic pairs. Based on these methods three novel robot designs are presented, demonstrating that the dynamic balance of spatially moving parallel robots is within reach.
Original language | English |
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Qualification | Doctor of Philosophy |
Awarding Institution |
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Supervisors/Advisors |
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Award date | 7 Feb 2020 |
Place of Publication | Enschede |
Publisher | |
Print ISBNs | 978-90-365-4937-0 |
DOIs | |
Publication status | Published - 7 Feb 2020 |