A Laser-Based Direct Cable Length Measurement Sensor for CDPRs
Accuracy improvement is an important research topic in the field of cable-driven parallel robots (CDPRs). One reason for inaccuracies of CDPRs are deviations in the cable lengths. Such deviations can be caused by the elongation of the cable due to its elasticity or creep behavior. For most common CD...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-04-01
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| Series: | Robotics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2218-6581/10/2/60 |
| _version_ | 1797536837856657408 |
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| author | Christoph Martin Marc Fabritius Johannes T. Stoll Andreas Pott |
| author_facet | Christoph Martin Marc Fabritius Johannes T. Stoll Andreas Pott |
| author_sort | Christoph Martin |
| collection | DOAJ |
| description | Accuracy improvement is an important research topic in the field of cable-driven parallel robots (CDPRs). One reason for inaccuracies of CDPRs are deviations in the cable lengths. Such deviations can be caused by the elongation of the cable due to its elasticity or creep behavior. For most common CDPRs, the cable lengths are controlled using motor encoders of the winches, without feedback about the actual elongation of the cables. To address this problem, this paper proposes a direct cable length measurement sensor based on a laser distance sensor. We present the mechanical design, the first prototype and an experimental evaluation. As a result, the measurement principle works well and the accuracy of the measured cable lengths is within −2.32 mm to +1.86 mm compared to a range from −5.19 mm to +6.02 mm of the cable length set with the motor encoders. The standard deviation of the cable length error of the direct cable length measurement sensor is 58% lower compared to the one set with the motor encoders. Equipping all cables of the cable robot with direct cable length measurement sensors results in the possibility to correct cable length deviations and thus increase the accuracy of CDPRs. Furthermore, it enables new possibilities like the automatic recalibration of the home pose. |
| first_indexed | 2024-03-10T12:06:29Z |
| format | Article |
| id | doaj.art-31b7dc1a096f4eb49736bc2093eb48e5 |
| institution | Directory Open Access Journal |
| issn | 2218-6581 |
| language | English |
| last_indexed | 2024-03-10T12:06:29Z |
| publishDate | 2021-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Robotics |
| spelling | doaj.art-31b7dc1a096f4eb49736bc2093eb48e52023-11-21T16:30:23ZengMDPI AGRobotics2218-65812021-04-011026010.3390/robotics10020060A Laser-Based Direct Cable Length Measurement Sensor for CDPRsChristoph Martin0Marc Fabritius1Johannes T. Stoll2Andreas Pott3Robot and Assistive Systems Department, Fraunhofer Institute for Manufacturing Engineering and Automation IPA, Nobelstrasse 12, D-70569 Stuttgart, GermanyRobot and Assistive Systems Department, Fraunhofer Institute for Manufacturing Engineering and Automation IPA, Nobelstrasse 12, D-70569 Stuttgart, GermanyRobot and Assistive Systems Department, Fraunhofer Institute for Manufacturing Engineering and Automation IPA, Nobelstrasse 12, D-70569 Stuttgart, GermanyInstitute for Control Engineering of Machine Tools and Manufacturing Units (ISW), University of Stuttgart, Seidenstrasse 36, D-70174 Stuttgart, GermanyAccuracy improvement is an important research topic in the field of cable-driven parallel robots (CDPRs). One reason for inaccuracies of CDPRs are deviations in the cable lengths. Such deviations can be caused by the elongation of the cable due to its elasticity or creep behavior. For most common CDPRs, the cable lengths are controlled using motor encoders of the winches, without feedback about the actual elongation of the cables. To address this problem, this paper proposes a direct cable length measurement sensor based on a laser distance sensor. We present the mechanical design, the first prototype and an experimental evaluation. As a result, the measurement principle works well and the accuracy of the measured cable lengths is within −2.32 mm to +1.86 mm compared to a range from −5.19 mm to +6.02 mm of the cable length set with the motor encoders. The standard deviation of the cable length error of the direct cable length measurement sensor is 58% lower compared to the one set with the motor encoders. Equipping all cables of the cable robot with direct cable length measurement sensors results in the possibility to correct cable length deviations and thus increase the accuracy of CDPRs. Furthermore, it enables new possibilities like the automatic recalibration of the home pose.https://www.mdpi.com/2218-6581/10/2/60cable-driven parallel robotsCDPRdirect cable length measurementDCLM-Sensorlaser distance sensorcable elongation |
| spellingShingle | Christoph Martin Marc Fabritius Johannes T. Stoll Andreas Pott A Laser-Based Direct Cable Length Measurement Sensor for CDPRs Robotics cable-driven parallel robots CDPR direct cable length measurement DCLM-Sensor laser distance sensor cable elongation |
| title | A Laser-Based Direct Cable Length Measurement Sensor for CDPRs |
| title_full | A Laser-Based Direct Cable Length Measurement Sensor for CDPRs |
| title_fullStr | A Laser-Based Direct Cable Length Measurement Sensor for CDPRs |
| title_full_unstemmed | A Laser-Based Direct Cable Length Measurement Sensor for CDPRs |
| title_short | A Laser-Based Direct Cable Length Measurement Sensor for CDPRs |
| title_sort | laser based direct cable length measurement sensor for cdprs |
| topic | cable-driven parallel robots CDPR direct cable length measurement DCLM-Sensor laser distance sensor cable elongation |
| url | https://www.mdpi.com/2218-6581/10/2/60 |
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