ABSTRACT
Wireless sensor networks have been very popular research field for the last couple of years. ZigBee is a new technology now being deployed for wireless sensor networks. ZigBee is a low data rate wireless network standard defined by the ZigBee Alliance and based on the IEEE 802.15.4.The ZigBee wireless network has some advantages compared with other wireless networks, it has the characteristics of low power, low price, highly secured and reliable, so implementing a remote motor control and monitoring system proves to have a good cost performance ratio.
This paper presents the implementation of a wireless sensor actor network (point to point) to control the speed of a DC motor from a remote location. Pulse Width Modulation technique provides the actual control. A feedback to measure the current speed is setup using Infra Red Sensor and fed to PIC16F877 Microcontroller directly. The conventional setup uses a frequency to voltage converter to find the speed whereas a new technique is used to calculate the speed from the IR sensor output without using frequency to voltage converter. The motor is controlled remotely with a ±5 rpm tolerance.
Keywords: Wireless Sensor Networks, ZigBee, Xbee, motor control HOST UNIT CIRCUIT DIAGRAM:
NODE UNIT CIRCUIT DIAGRAM:
OBSERVED GRAPH:
Xbee Configuration using X-CTU Software :
ORIGINAL PICTURES:
HOST UNIT:
NODE UNIT:
CONCLUSION:
Different speeds are maintained at the given set speed by varying the duty cycle of PWM using PIC16F877A MICROCONTROLLER and a wireless sensor ZIGBEE with a resolution of ±5 rpm tolerance .The measured speed values are transferred by serial interface to the PC and are logged into a text file and are visualized with the aid of XCTU front.
The radius of the location under observation can be increased by 150 meters using an Xbee-Pro instead of ordinary Xbee. Alternatively, using a mesh network with Xbee the distance between the host and sensor node is not a crucial parameter. The acquired data can be further analyzed or used for control of the remote process.
REFERENCES:
[1] H. Taub and DL Schilling. Principles of communication systems. McGraw Hill, New York, Second edition, 1986
[2] Low-Rate Wireless Personal Area Networks: Enabling Wireless Sensors with IEEE 802.15.4 by Jose A. Gutierrez ,Edgar H. Callaway, Jr, Raymond L Barrett, Jr. Published by Standards Information Network IEEE Press November 2003
[3] Wireless Communications: Principles & Practice, T.S. Rappaport. PH 1996
[4] ZigBee Wireless Networking Drew Gislason Newnes Press 2007
[5] http://www.zigbee.org/en/index.asp: Zigbee Official website
[6]http://www.maxstream.net/products/xbee/datasheet_XBee_OEM_RF-Modules.pdf:Maxtream’s Transceiver Xbee
[7]Tanenbaum, A.S., Computer Networks, 3rd ed., Prentice-Hall International 1996.
Posted by:
SANTHOSH BHARADWAJ REDDY
email: bharadwaj874@gmail.com
