CHAPTER 3. CONCLUSION AND FUTURE WORKS
3.2 Future Works
The future works are summarized as follows:
A. Measurement of three-DOF orientation B. Magnetic field design
C. Torque estimation and control for spherical motor
The orientation measurement system presented in this thesis can measure two orientation angles.
Some application requires three orientation angle, not only and Euler angle but also spinning motion γ. Therefore, three-DOF orientation measurement system has to be developed to apply some
The magnetic source is important parts in magnetic tracing system. A cylindrical PM used in this system can measure only two orientaion angles due to the symmetry of the magnetization of PM along the z axis. Some researchers suggested to measure position/orienataion of magnetic source using multi- magnet [24]. Combination of magnets or another shape of PM can overcome this limitation and can make system more simple.
The dynamic model of spherical motor can be derived using Lagrange formulation [20]. The orientation can be used not only for orientation/position control of spherical motor but also for torque estimation because torque is derived by orientation defined as Euler angles (, , γ).
REFERENCES
[1] H. Z. Jin, H. Lu, S. K. Cho and J. M. Lee, "Nonlinear compensation of a new noncontact joystick using the universal joint mechanism," IEEE/ASME Trans on Mechatronics, vol. 12, pp. 549-556, 2007.
[2] C. Schott, R. Racz, and S. Huber, "CMOS three axis hall sensors and joystick application,”
IEEE Sensors. Conference., vol. 2, pp. 977-980, 2004.
[3] G. S. Chirikjian and D. Stein, "Kinematic design and commutation of a spherical stepper motor," IEEE/ASME Trans on Mechatronics, vol. 4, pp. 342-353, 1999.
[4] K.-M. Lee and H. Son, “Distributed multipole model for design of permanent-magnet-based actuators,” IEEE/ASME Trans on Magnetics, vol. 43, pp. 3904-3913, 2007.
[5] L. Zhang and W. Chen, "A robust adaptive iterative learning control for trajectory tracking of permanent-magnet spherical actuator" IEEE Trans on Industrial Electronics, vol. 63, pp. 291- 301, 2016.
[6] G. Seyfarth, A. Bhatia, O. Sassnick, M. Shomin, M. Kumnagi and R. Hollis, “Initial results for a ballbot driven with a spherical induction motor,” IEEE International Conference on Robotics and Automation (ICRA), Stockholm, Sweden, pp. 3771-3776, 2016.
[7] H. Son and K.-M. Lee, "Open-loop controller design and dynamic characteristics of a spherical wheel motor," IEEE Trans on Industrial Electronics, vol.57, no.10, pp. 3475-3482, 2010.
[8] S. M. Lee and H. Son, "Multi-degree of freedom motion platform based on spherical wheels,"
IEEE/ASME Trans on Mechatronics, vol. 22, pp. 2121-2129, 2017.
[9] H. Arioui, L. Nehaoua, S. Hima, N. S’eguy, and S. Espi’e, "Mechatronics, design, and modeling of a motorcycle riding simulator," IEEE/ASME Trans on Mechatronics, vol. 15, pp.
805-818, 2010.
[10] K. L. Cappel and N. Marlton, "Motion simulator," U.S patent 32 95 224, Jan.3, 1967.
[11] M. Wapler, V. Urban, T. Weisener, J. Stallkamp, M. Durr, and A. Hiller, "A stewart platform
[12] K.-M. Lee, R. Roth, and Z. Zhou, "Dynamic modeling and control of a ball joint-like variable- reluctance spherical motor," Journal of Dynamic Systems Measurement and Control, vol. 118, pp. 29-40, 1996.
[13] K.-M. Lee and D. Zhou, "A real-time optical sensor for simultaneous measurement of three- DOF motions," IEEE/ASME Trans on Mechatronics, vol. 9, pp. 499-507, 2004.
[14] H. Garner, M. Klement, and K.-M. Lee, "Design and analysis of an absolute non-contact orientation sensor for wrist motion control," IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), pp. 69-74, 2001.
[15] C. Hu, M. Q.-H Meng, T. Mei, J. Pu, c. Hu, X. Wang and Y. Chan, "A linear algorithm for tracing magnet’s position and orientation by using 3-axis magnetic sensors," IEEE Trans on Magnetics, vol 43, no. 12, pp. 4096-4101, 2007.
[16] K.-M. Lee and H. Son, “Two-DOF magnetic orientation sensor using distributed multipole model for spherical wheel motor,” Mechatronics, pp. 156-165, 2011.
[17] G. Jinjun, C. Bak and H. Son, "Design of a sensing system for a spherical motor based on hall effect sensors and neural networks," IEEE International Conference on Advanced Intelligent Mechatronics (AIM), Busan, Korea, pp. 1410-1414, 2015.
[18] S. Foong, K.-M. Lee, and K. Bai, "Magnetic field-based sensing method for spherical joint,"
IEEE International Conference on Robotics and Automation (ICRA), Anchorage, AK, pp.
5447-5452, 2010.
[19] S. Foong, K.-M. Lee, and K. Bai, "Harnessing embedded magnetic fields for angular sensing with nanodegree accuracy," IEEE/ASME Trans on Mechatronics, vol. 17, pp. 687-696, 2012.
[20] K.-M. Lee and K. Bai, “Direct field-feedback control of a ball-joint-like permanent-magnet spherical motor,” IEEE/ASME Trans on Mechatronics, vol. 19 pp. 975-986, 2014.
[21] E. Paperno, I. Sasada, and E. Leonovich, “A new method for magnetic position and orientation tracking,” IEEE/ASME Trans on Magnetics, pp. 1938-1940, 2001.
[22] H. Son and W. Fang, “Optimization of measuring magnetic fields for position and orientation tracking,” IEEE/ASME Trans on Mechatronics, vol. 16 pp. 440-448, 2011.
[23] Product information of Goniometer, [Online]. Available: https://www.owis.eu, 2011.
[24] X. Qiu, S. Song, M. Q.-H. Meng, “A novel 6-D pose detection method using opposing-magnet pair system”, IEEE Sensors Journal, vol. 17, pp. 2642-2643, 2017
ACKNOWLEDGEMENT
First of all, I would like to express my sincere gratitude to my advisor Assoc/Prof Hungsun Son for his academic guidance throughout this research. He is very knowledgeable and always coming up with new ideas. It inspired me and played an important role in the successful completion of this thesis. He also gave me a generous help when I started my graduate life and it was very helpful to me. It was an honor for me to work under Prof. Hungsun Son and I always respect him as my mentor.
I want to thank the research former members Wu Fang and Guo Jinjun. During this research, I was able to study research background with their previous research.
I also want to thank my companions in the Electromechanical Systems and Control Lab(ESCL) Jiyun Jeon, Myunggun Kim, Seongmin Lee, Chanbeom Bak, Minho Shin, Hoyoung Kim, Wonmo Chungm, Sangheon Lee and Soyoon Kim for their helpful support and advices. Especially, I have obtained numerous suggestions and feedback from group meeting members Jiyun Jeon, Chanbeom Bak and Wonmo Chung. Their assistances are greatly appreciated.
I would like to thank my family Yeonok Shin, Sugeun Kim and Jisun Kim for their long-time supports throughout my educational career. Without their support, it would have been impossible for me to complete this work.