本論文主旨在於實現可攜式身體活動量感測系統，本系統由配戴於人體之
活動量感測器所組成，分別為主感測器與為副感測器。主、副感測器皆具備微
控制器模組、電源管理模組、感測器模組、無線通訊模組。其中感測器模組由
加速度感測器所組成，負責感測使用者身體活動量所產生之加速度訊號。無線
感測模組方面，主感測器具備藍芽通訊模組及無線射頻模組、副感測器則具備
無線射頻模組；無線射頻模組負責於主、副感測器之間同步時序及傳輸資料，
副感測器將感測資料傳輸至主感測器並匯集於主感測器之記憶單元模組中，再
由主感測器之藍芽通訊模組將資料傳輸到外部分析裝置進行分析。為了增升本
系統之效率，本論文實現了1)高時間解析度之同步取樣及2) 低功率策略，兩
種優化策略於可攜式身體活動量感測系統。其中高時間解析度之同步取樣可將
主、副感測器之間的取樣時間誤差降低於5 毫秒之內，低功率策略可使耗電減
少為未做低功率策略之感測器50%以上。

This thesis presents a portable physical activity recording system consisting of a host sensor and a client sensor. Both host and client sensors are composed of a microcontroller module, a power management module, a sensing module and a wireless communication module. The main component of the sensing module is a triaxial accelerometer which is charge of generating acceleration signal based on user’s physical activity. For the wireless communication module, the host sensor contains a Bluetooth communication module and a radio frequency (RF) module while the client sensor has a RF module only. The RF modules in the host and client sensors are responsible for synchronization and data transmission. The recorded data in the client are transmitted to the memory module of the host sensor, and send to a PC for further analysis by the Bluetooth module of the host sensor. To increase the efficiency of the system, the system implements the following two tasks: 1) high-resolution synchronization and 2) low-power strategy. Experimental results show that the proposed high-resolution synchronization can keep the sampling time error within 5 ms between the host and client sensors; the low power strategy can save 50% power consumption.

[1]http://www.mmh.org.tw/taitam/famme/health_promotion.htm
[2]M. P. Rothney, M. Neumann, and A. Béziat, “An artificial neural network model of energy expenditure using nonintegrated acceleration signals,” Eur. Journal of Applied Physiology, vol. 103, no. 4, pp. 1419-1427, 2007.
[3]S. E. Crouter, J. R. Churilla, and D. R. Bassett Jr, “Estimating energy expenditure using accelerometers,” Eur. Journal of Applied Physiology, vol. 98, no. 6, pp. 601-612, 2006.
[4]D. R. Bassett Jr, B. E. Ainsworth, A. M. Swartz, S. J. Strath, W. L. O’brien, and G. A. King, “Validity of four motion sensors in measuring moderate intensity physical activity,” Medicine & Science in Sports & Exercise, vol. 32, no. 9, pp. S471-480, 2000.
[5]A. G. Brooks, S. M. Gunn, R. T. Withers, C. J. Gore, and J. L. Plummer, “Predicting walking METs and energy expenditure from speed or accelerometry,” Medicine & Science in Sports & Exercise, vol. 37, no. 7, pp. 1216-1223, 2005.
[6]K. Y. Chen and D. R. Bassett, “The technology of accelerometry-based activity monitors: current and future,” Medicine & Science in Sports & Exercise, vol. 37, no. 11, pp. S490-S500, 2005.
[7]R. J. Cole, D. F. Kripke, W. Gruen, D. J. Mullaney and J. C. Gillin, “Technical note automatic sleep/wake identification from wrist activity,” Sleep, vol. 15, no. 5, pp. 461-469, 1992.
[8]A. Sadeh, “Evaluating night wakings in sleep-disturbed infants: a methodological study of parental reports and actigraphy,” SLEEP-NEW YORK-, vol. 19, pp. 757-762, 1996.
[9]J. Brooks 3rd, L. Friedman, D. Bliwise, and J. Yesavage, “Use of the wrist actigraph to study insomnia in older adults,” Sleep, vol. 16, no. 2, p. 151, 1993.
[10]M. L. FRUIN and J. W. RANKIN, “Validity of a multi-sensor armband in estimating rest and exercise energy expenditure,” Medicine & Science in Sports & Exercise, vol. 36, no. 6, p. 1063, 2004.
[11]E. J. W. Van Someren, B. F. M. Vonk, W. A. Thijssen, J. D. Speelman, P. R. Schuurman, M. Mirmiran, and D. F. Swaab, “A new actigraph for long-term registration of the duration and intensity of tremor and movement,” IEEE Transactions on Biomedical Engineering, vol. 45, no. 3, pp. 386-395, 1998.
[12]T. Tanaka, S. Yamashita, K. Aiki, H. Kuriyama, and K. Yano, “Life Microscope: continuous daily-activity recording system with tiny wireless sensor,” in Proc. of 5th International Conference on Networked Sensing Systems, Kanazawa pp. 162-165,2008.
[13]G. Mathur, P. Desnoyers, P. Chukiu, D. Ganesan, and P. Shenoy, “Ultra-low power data storage for sensor networks,” ACM Transactions on Sensor Networks (TOSN), vol. 5, no. 4, p. 33, 2009.
[14]D. Lymberopoulos and A. Savvides, “XYZ: a motion-enabled, power aware sensor node platform for distributed sensor network applications,” in Proc. of the 4th international symposium on Information pp. 63-es,2005.
[15]A. Kansal, J. Hsu, S. Zahedi, and M. B. Srivastava, “Power management in energy harvesting sensor networks,” ACM Transactions on Embedded Computing Systems (TECS), vol. 6, no. 4, pp. 32-es, 2007.
[16]T. Voigt, H. Ritter, and J. Schiller, “Utilizing solar power in wireless sensor networks,” in Proc. of 28th Annual IEEE International Conference on Local Computer Networks, pp. 416-422,2003.
[17]Chen Min, Peng Chenglin, Guo Xingming, and Lei Jianmei, “A novel MAC protocol for wireless physiological information sensor,” in Proc. of the 4th IEEE/EMBS International Summer School and Symposium on Medical Devices and Biosensors, 2007.
[18]F. Forouzandeh, A. Mohamed, M. Sawan, and F. Awwad, “TBCD-TDM: novel ultra-low energy protocol for implantable wireless body sensor networks,” in Proc. Global Telecommunications Conference, Honolulu, HI pp. 1-6,2009.
[19]J. Plomp, M. Heiskanen, M. Hillukkala, T. Heikkila, J. Rehu, N. Lambert, V. van Acht, and T. Ahola, “Considerations for synchronization in body area networks for human activity monitoring,” International Journal of Wireless Information Networks, pp. 1-15.
[20]Y. Ohta, Y. Sugaya, H. Igarashi, T. Ohtsuki, and K. Taguchi, “Share-Z: Client/server depth sensing for see-through head-mounted displays,” Presence: Teleoperators & Virtual Environments, vol. 11, no. 2, pp. 176-188, 2002.
[21]Microchip Technology Inc., Microchip PIC24FJ64GA002 Data Sheet, http://ww1.microchip.com/downloads/en/DeviceDoc/39881b.pdf
[22]C. V. C. Bouten, K. T. M. Koekkoek, M. Verduin, R. Kodde, and J. D. Janssen, “A triaxial accelerometer and portable data processing unit for assessment the assessment of daily physical activity,” IEEE Trans. Biomedical Engineering, vol. 44, no. 3, pp. 136-147, 1997.
[23]http://www.freescale.com/files/sensors/doc/data_sheet/MMA7455L.pdf
[24]CSR, http://www.csr.com/home.php
[25]Nordic, http://www.nordicsemi.com
[26]MXIC, http://www.mxic.com.tw/QuickPlace/hq/Main.nsf/h_Toc/5c179475fbb1-
d010482574440028bdf4/?OpenDocument