Parallel Coupled Micro-Macro Actuators
This thesis presents a new actuator system consisting of a micro-actuator and a macro-actuator coupled in parallel via a compliant transmission. The system is called the Parallel Coupled Micro-Macro Actuator, or PaCMMA. In this system, the micro-actuator is capable of high bandwidth force contr...
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| Language: | en_US |
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2004
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| Online Access: | http://hdl.handle.net/1721.1/7066 |
| _version_ | 1826213636288282624 |
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| author | Morrell, John Bryant |
| author_facet | Morrell, John Bryant |
| author_sort | Morrell, John Bryant |
| collection | MIT |
| description | This thesis presents a new actuator system consisting of a micro-actuator and a macro-actuator coupled in parallel via a compliant transmission. The system is called the Parallel Coupled Micro-Macro Actuator, or PaCMMA. In this system, the micro-actuator is capable of high bandwidth force control due to its low mass and direct-drive connection to the output shaft. The compliant transmission of the macro-actuator reduces the impedance (stiffness) at the output shaft and increases the dynamic range of force. Performance improvement over single actuator systems was expected in force control, impedance control, force distortion and reduction of transient impact forces. A set of quantitative measures is proposed and the actuator system is evaluated against them: Force Control Bandwidth, Position Bandwidth, Dynamic Range, Impact Force, Impedance ("Backdriveability'"), Force Distortion and Force Performance Space. Several theoretical performance limits are derived from the saturation limits of the system. A control law is proposed and control system performance is compared to the theoretical limits. A prototype testbed was built using permanenent magnet motors and an experimental comparison was performed between this actuator concept and two single actuator systems. The following performance was observed: Force bandwidth of 56Hz, Torque Dynamic Range of 800:1, Peak Torque of 1040mNm, Minimum Torque of 1.3mNm. Peak Impact Force was reduced by an order of magnitude. Distortion at small amplitudes was reduced substantially. Backdriven impedance was reduced by 2-3 orders of magnitude. This actuator system shows promise for manipulator design as well as psychophysical tests of human performance. |
| first_indexed | 2024-09-23T15:52:24Z |
| id | mit-1721.1/7066 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:52:24Z |
| publishDate | 2004 |
| record_format | dspace |
| spelling | mit-1721.1/70662019-04-10T11:52:30Z Parallel Coupled Micro-Macro Actuators Morrell, John Bryant This thesis presents a new actuator system consisting of a micro-actuator and a macro-actuator coupled in parallel via a compliant transmission. The system is called the Parallel Coupled Micro-Macro Actuator, or PaCMMA. In this system, the micro-actuator is capable of high bandwidth force control due to its low mass and direct-drive connection to the output shaft. The compliant transmission of the macro-actuator reduces the impedance (stiffness) at the output shaft and increases the dynamic range of force. Performance improvement over single actuator systems was expected in force control, impedance control, force distortion and reduction of transient impact forces. A set of quantitative measures is proposed and the actuator system is evaluated against them: Force Control Bandwidth, Position Bandwidth, Dynamic Range, Impact Force, Impedance ("Backdriveability'"), Force Distortion and Force Performance Space. Several theoretical performance limits are derived from the saturation limits of the system. A control law is proposed and control system performance is compared to the theoretical limits. A prototype testbed was built using permanenent magnet motors and an experimental comparison was performed between this actuator concept and two single actuator systems. The following performance was observed: Force bandwidth of 56Hz, Torque Dynamic Range of 800:1, Peak Torque of 1040mNm, Minimum Torque of 1.3mNm. Peak Impact Force was reduced by an order of magnitude. Distortion at small amplitudes was reduced substantially. Backdriven impedance was reduced by 2-3 orders of magnitude. This actuator system shows promise for manipulator design as well as psychophysical tests of human performance. 2004-10-20T20:27:59Z 2004-10-20T20:27:59Z 1996-01-01 AITR-1563 http://hdl.handle.net/1721.1/7066 en_US AITR-1563 2941861 bytes 2363711 bytes application/postscript application/pdf application/postscript application/pdf |
| spellingShingle | Morrell, John Bryant Parallel Coupled Micro-Macro Actuators |
| title | Parallel Coupled Micro-Macro Actuators |
| title_full | Parallel Coupled Micro-Macro Actuators |
| title_fullStr | Parallel Coupled Micro-Macro Actuators |
| title_full_unstemmed | Parallel Coupled Micro-Macro Actuators |
| title_short | Parallel Coupled Micro-Macro Actuators |
| title_sort | parallel coupled micro macro actuators |
| url | http://hdl.handle.net/1721.1/7066 |
| work_keys_str_mv | AT morrelljohnbryant parallelcoupledmicromacroactuators |