Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks
This paper presents a universal approach to shaping the mechanical properties of the interaction between a collaborative robot and its environment through an end-effector Cartesian compliance shaping. More specifically, the focus is on the class of kinematically redundant robots, for which a novel r...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-12-01
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| Series: | Machines |
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| Online Access: | https://www.mdpi.com/2075-1702/11/1/35 |
| _version_ | 1797439466057498624 |
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| author | Branko Lukić Kosta Jovanović Leon Žlajpah Tadej Petrič |
| author_facet | Branko Lukić Kosta Jovanović Leon Žlajpah Tadej Petrič |
| author_sort | Branko Lukić |
| collection | DOAJ |
| description | This paper presents a universal approach to shaping the mechanical properties of the interaction between a collaborative robot and its environment through an end-effector Cartesian compliance shaping. More specifically, the focus is on the class of kinematically redundant robots, for which a novel redundancy reconfiguration scheme for online optimization of the Cartesian compliance of the end-effector is presented. The null-space reconfiguration aims to enable the more efficient and versatile use of collaborative robots, including robots with passive compliant joints. The proposed approach is model-based and gradient-based to enable real-time computation and reconfiguration of the robot for Cartesian compliance while ensuring accurate position tracking. The optimization algorithm combines two coordinate frames: the global (world) coordinate frame commonly used for end-effector trajectory tracking; and the coordinate frame fixed to the end-effector in which optimization is computed. Another attractive feature of the approach is the bound on the magnitude of the interaction force in contact tasks. The results are validated on a torque-controlled 7-DOF KUKA LWR robot emulating joint compliance in a quasi-static experiment (the robot exerts a force on an external object) and a peg-in-hole experiment emulating an assembly task. |
| first_indexed | 2024-03-09T11:54:20Z |
| format | Article |
| id | doaj.art-3f3d2243f3554d76b1561f0b877156cc |
| institution | Directory Open Access Journal |
| issn | 2075-1702 |
| language | English |
| last_indexed | 2024-03-09T11:54:20Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Machines |
| spelling | doaj.art-3f3d2243f3554d76b1561f0b877156cc2023-11-30T23:10:59ZengMDPI AGMachines2075-17022022-12-011113510.3390/machines11010035Online Cartesian Compliance Shaping of Redundant Robots in Assembly TasksBranko Lukić0Kosta Jovanović1Leon Žlajpah2Tadej Petrič3School of Electric Engineering, University of Belgrade, 11120 Belgrade, SerbiaSchool of Electric Engineering, University of Belgrade, 11120 Belgrade, SerbiaJožef Stefan Institute, 1000 Ljubljana, SloveniaJožef Stefan Institute, 1000 Ljubljana, SloveniaThis paper presents a universal approach to shaping the mechanical properties of the interaction between a collaborative robot and its environment through an end-effector Cartesian compliance shaping. More specifically, the focus is on the class of kinematically redundant robots, for which a novel redundancy reconfiguration scheme for online optimization of the Cartesian compliance of the end-effector is presented. The null-space reconfiguration aims to enable the more efficient and versatile use of collaborative robots, including robots with passive compliant joints. The proposed approach is model-based and gradient-based to enable real-time computation and reconfiguration of the robot for Cartesian compliance while ensuring accurate position tracking. The optimization algorithm combines two coordinate frames: the global (world) coordinate frame commonly used for end-effector trajectory tracking; and the coordinate frame fixed to the end-effector in which optimization is computed. Another attractive feature of the approach is the bound on the magnitude of the interaction force in contact tasks. The results are validated on a torque-controlled 7-DOF KUKA LWR robot emulating joint compliance in a quasi-static experiment (the robot exerts a force on an external object) and a peg-in-hole experiment emulating an assembly task.https://www.mdpi.com/2075-1702/11/1/35Cartesian compliancecollaborative robotsnull spaceredundant robots |
| spellingShingle | Branko Lukić Kosta Jovanović Leon Žlajpah Tadej Petrič Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks Machines Cartesian compliance collaborative robots null space redundant robots |
| title | Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks |
| title_full | Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks |
| title_fullStr | Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks |
| title_full_unstemmed | Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks |
| title_short | Online Cartesian Compliance Shaping of Redundant Robots in Assembly Tasks |
| title_sort | online cartesian compliance shaping of redundant robots in assembly tasks |
| topic | Cartesian compliance collaborative robots null space redundant robots |
| url | https://www.mdpi.com/2075-1702/11/1/35 |
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