Development of a new suction gripper for gripping under-constrained workpiece with minimized contact
When gripping delicate workpieces such as a silicon wafer, contact should be minimized to protect the workpiece. Some existing suction grippers can grip a workpiece with only three contact points on its upper surface, which is minimal to fully constrain the workpiece. Further reducing the contact po...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2024
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| Online Access: | https://hdl.handle.net/10356/179083 |
| _version_ | 1826116542267392000 |
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| author | Shi, Kaige Li, Xin |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Shi, Kaige Li, Xin |
| author_sort | Shi, Kaige |
| collection | NTU |
| description | When gripping delicate workpieces such as a silicon wafer, contact should be minimized to protect the workpiece. Some existing suction grippers can grip a workpiece with only three contact points on its upper surface, which is minimal to fully constrain the workpiece. Further reducing the contact points will make the workpiece under-constrained and thus difficult to grip. This paper develops a new suction gripper that can grip an under-constrained workpiece with only two contact points at the edge of its upper surface. The uniqueness of the new gripper lies in that it uses feedback control to stabilize the unstable motion of the under-constrained workpiece. First, to overcome the negative-stiffness effect that makes the under-constrained gripping unstable, a zero-stiffness suction unit based on closed-loop pressure feedback is developed via optimal design. Next, a cooperative actuating mechanism based on four suction units is designed to actuate the workpiece in four different DOFs individually, so that the workpiece can be levitated stably with the contact forces being controlled. Finally, the dynamics of the gripping system is modeled, and an adaptive robust controller is designed based on the dynamics model. With the proposed controller, the gripper can handle workpieces with unknown inertial parameters and irregular upper surfaces. Experiments were conducted to verify the new suction gripper with the proposed controller. |
| first_indexed | 2024-10-01T04:13:25Z |
| format | Journal Article |
| id | ntu-10356/179083 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:13:25Z |
| publishDate | 2024 |
| record_format | dspace |
| spelling | ntu-10356/1790832024-07-17T04:36:08Z Development of a new suction gripper for gripping under-constrained workpiece with minimized contact Shi, Kaige Li, Xin School of Electrical and Electronic Engineering Engineering Adaptive robust control Cooperative actuating mechanism When gripping delicate workpieces such as a silicon wafer, contact should be minimized to protect the workpiece. Some existing suction grippers can grip a workpiece with only three contact points on its upper surface, which is minimal to fully constrain the workpiece. Further reducing the contact points will make the workpiece under-constrained and thus difficult to grip. This paper develops a new suction gripper that can grip an under-constrained workpiece with only two contact points at the edge of its upper surface. The uniqueness of the new gripper lies in that it uses feedback control to stabilize the unstable motion of the under-constrained workpiece. First, to overcome the negative-stiffness effect that makes the under-constrained gripping unstable, a zero-stiffness suction unit based on closed-loop pressure feedback is developed via optimal design. Next, a cooperative actuating mechanism based on four suction units is designed to actuate the workpiece in four different DOFs individually, so that the workpiece can be levitated stably with the contact forces being controlled. Finally, the dynamics of the gripping system is modeled, and an adaptive robust controller is designed based on the dynamics model. With the proposed controller, the gripper can handle workpieces with unknown inertial parameters and irregular upper surfaces. Experiments were conducted to verify the new suction gripper with the proposed controller. National Research Foundation (NRF) This work is supported by the National Research Foundation, Singapore, under the NRF Medium Sized Centre scheme (CARTIN) and the National Key Research and Development Program of China (No. 2023YFC3806800). 2024-07-17T04:36:08Z 2024-07-17T04:36:08Z 2024 Journal Article Shi, K. & Li, X. (2024). Development of a new suction gripper for gripping under-constrained workpiece with minimized contact. Robotics and Computer-Integrated Manufacturing, 90, 102794-. https://dx.doi.org/10.1016/j.rcim.2024.102794 0736-5845 https://hdl.handle.net/10356/179083 10.1016/j.rcim.2024.102794 2-s2.0-85196020753 90 102794 en CARTIN Robotics and Computer-Integrated Manufacturing © 2024 Published by Elsevier Ltd. All rights reserved. |
| spellingShingle | Engineering Adaptive robust control Cooperative actuating mechanism Shi, Kaige Li, Xin Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title | Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title_full | Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title_fullStr | Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title_full_unstemmed | Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title_short | Development of a new suction gripper for gripping under-constrained workpiece with minimized contact |
| title_sort | development of a new suction gripper for gripping under constrained workpiece with minimized contact |
| topic | Engineering Adaptive robust control Cooperative actuating mechanism |
| url | https://hdl.handle.net/10356/179083 |
| work_keys_str_mv | AT shikaige developmentofanewsuctiongripperforgrippingunderconstrainedworkpiecewithminimizedcontact AT lixin developmentofanewsuctiongripperforgrippingunderconstrainedworkpiecewithminimizedcontact |