Force control of a spiral motor and its application to musculoskeletal biped robot

2013 IEEE International Conference on Mechatronics (ICM)

2013

In this paper, we proposed a control method for a spiral motor equipped with a surface-mounted permanent magnet. The zero-power controller discussed in this paper compensates for roughness of gap length, and realizes longstroke continuous-path position control. The simulations and experiment result of magnetic levitation control and position control using a zero-power controller show that the controls function successfully.

Section: Introductionmentioning

confidence: 99%

Long-stroke continuous-path position control of an SPM spiral motor

Suzuki

2013 IEEE International Conference on Mechatronics (ICM)

2013

“…A method to expand gap area without increasing volume is to design a motor of a special 3-D structure. Authors have proposed a new helical structure of a direct-drive system that meets the requirements of safety, performance, and compactness [37]- [41]. The motor has a helical-shape mover, which moves in a helical-shape stator without contact.…”

Section: Introductionmentioning

confidence: 99%

Control of an Interior Permanent-Magnet Screw Motor With Power-Saving Axial-Gap Displacement Adjustment

IEEE Trans. Ind. Electron.

Suenaga

Koyama

2014

Self Cite

This paper proposes position and force control of a screw motor with power-saving axial-gap displacement adjustment. The motor has a helical-shape mover, which moves in a helical-shape stator without contact. Due to the fabrication process, the actual helical shapes of the mover and the stator are not completely uniform and the air-gap length between the mover and the stator slightly changes depending on the mover rotation angle. The d-axis current remains a finite value and copper loss arises even when the mover is located at the center between the stator cores. A power-saving axial-gap displacement adjustment method is proposed to solve this problem. The proposed control is experimentally verified.

“…Besides, we have designed gap, position, and force controllers for the motor. By using these controllers, the magnetic levitation and the desired thrust motion are achieved (7) . To reduce electric power for magnetic levitation, it is necessary for the axial-gap to be at a neutral point.…”

Section: Introductionmentioning

confidence: 99%

Zero Power Control Based on External Force Feedback for Helical Motor

Koyama

2016

IEEJ Journal IA

Self Cite

For an assist device, a safe and compact high output actuator is desired. The authors have proposed a helical motor that consists of a helical mover and stator. In the gap control of this motor, zero power control is applied to save power for magnetic levitation. However, when a disturbance force is imposed upon the motor, the gap response with the zero power controller has an inverse response. To solve this problem, a new zero power control based on external force feedback is proposed, which is used to generate both the gap displacement and gap velocity references. Experimental results and a mathematical analysis show that the proposed method suppresses the inverse response well in position control and force control.