Abstract
Rotary encoders, which are mainly used to feedback the angle of the robot arm to the robot controller system, are widely used in industrial and robotic applications. While optical and magnetic rotary encoders are dominant in the market, capacitive rotary encoders are also gaining interest for their simple design, ability to miniaturize and being absolute encoders insensitive to magnetic field variations. In this study, a new economical capacitive rotary encoder based on analog synchronous demodulation is developed. Analog synchronous demodulation technique is used for the first time in the literature as far as known to the authors for capacitive rotary encoders. It is chosen as it is quite robust, simple and economical. A compact mechanical body is developed by 3D printing. After packaging, the sensor is fixed to a motor for testing. The developed encoder shows 2880 pulse/rotation resolution and repeatable output under different temperature environments.
Similar content being viewed by others
References
Brasseur G (1996) A robust capacitive angular-position sensor. In: Proceedings of instrumentation and measurement technology conference, pp 1081–1086
Baxter LK (1977) Capacitive sensors, design and applications. IEEE Press, New York
Falkner AH (1994) The use of capacitance in the measurement of angular and linear displacement. IEEE Trans Instrum Meas 43:939–942
Erismis MA (2013) Design and modelling of a new robust multi-mass coupled-resonator family with dynamic motion amplification. Microsyst Technol 19:1105–1110
Brasseur G (1998) A capacitive finger-type angular-position and angular-speed. In: IEEE instrumentation and measurement technology conference, pp 967–972
Ferrari V, Ghisla A, Marioli D, Taroni A (2006) Capacitive angular-position sensor with electrically floating conductive rotor and measurement redundancy. IEEE Trans Instrum Meas 55:514–520
Gassula M, Li X, Meijer GCM, Van der Ham L, Spronck JW (2003) A contactless capacitive angular-position sensor. IEEE Sens J 35:607–614
Kennel RM, Basler St (2008) New developments in capacitive encoders for servo drives. SPEEDAM 2008:190–195
Cermak SP, Brasseur G (2001) A planar capacitive sensor for angular measurement. In: IEEE instrumentation and measurement technology conference, pp 1393–1396
Zheng D, Zhang S, Wang S, Hu C, Zhao X (2015) A capacitive rotary encoder based on quadrature modulation and demodulation. IEEE Trans Instrum Meas 64:143–153
Hou B, Zhou B, Song M, Lin Z, Zhang R (2016) A novel single-excitation capacitive angular position sensor design. Sensors 16:1196–1211
Netzer Y (2002) Capacitive displacement encoder. US Patent, US 6,492,911 B1
Kimura F, Gondo M, Yamamoto A, Higuchi T (2009) Resolver compatible capacitive rotary position sensor. In: Industrial electronics, pp 1923–1928
Ukil A, Shah VH, Deck B (2011) Fast computation of arctangent functions for embedded applications, a comparative analysis. In: IEEE international symposium on industrial electronics (ISIE), pp 1206–1211
Acknowledgements
This work is sponsored by TUBITAK, Project No. 114E567.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Karali, M., Karasahin, A.T., Keles, O. et al. A new capacitive rotary encoder based on analog synchronous demodulation. Electr Eng 100, 1975–1983 (2018). https://doi.org/10.1007/s00202-018-0677-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00202-018-0677-9