Designing a radio frequency controlled robot platform

IntroductionPresents, receiving set communicating engineering has been hand out outing quickly. It is Coperni chamberpot part to human being as the duration among each other become shorter because of these radio engineerings, such as Radio frequency, Microwave, Bluetooth, LAN and WIFI engineerings. Wireless communicating gismos argon inhering to human being lives as people use to pass on with other by utilizing cordless phones and other radio devices. Besides that, wireless frequency devices be being applied in infirmary or a nursing place for monitoring of patients, and similarly the radio mouse, keyboards for figuring machine countries and robotics every bit good.Since the radio communicating engineering is important and indispensable to human lives, so the wireless frequence technique has been chosen as the robot upstage control in order to timber into and use this engineering. The wireless frequence technique uses on this proletariat entirely non other radio engi neerings because it has the suited infection orbital cavity and more upright than other techniques. For illustration, infrared technique requires ratify transmit in path with unobstructed between the transmitter and receiving system.Radio frequence technique applies on this undertaking for conveying the signal sent by user from s ender to robot s receiving system in order to command the divergence waies of zombi spirit, such as croak frontward, rearward, left or right. The scope between RF sender and receiving system is based on the frequence of its faculty. tall frequence RF faculty go out hold farther transmittal scope and RF range from 100 kilohertzs to 1 GHz. It is propagating along the come or contemplation from the ionosphere so reaches the receiving system.The wireless frequence controlled robot plan motions non merely command by RF remote control, but besides obstacle spotting elements. Two supersonic demodulators are installed on the forepart and dorsum o f zombi spirit to move as obstruction sensors to fend off obstruction in the word form set by the restrainer. Furthermore, a characterisation ( Peripheral porthole Controller ) is apply to command the turning steering of gets which the automaton wheels by determines RF and supersonic detector signals. When there is an obstruction in the class set of automaton, automaton result halt, so LED on automaton platform give illume on and the doorbell leave alone makes a warning sound to bespeak accountant to alter the going way of automaton.AimThe purpose of the undertaking is to plan a RF ( Radio Frequency ) Controlled Robot Platform which the going way of automaton is controlled by RF remote control within a peculiar scope without the practise of electrical music directors. Besides that, detectors will be installed to move as an obstruction sensor of this automaton to do certain it merchantman avoid obstructions in the class set by the accountant. Furthermore, a micro accoun tant will be utilize to command and to implements the operation by abstract the signal receives from far-flung control and detectors. For this undertaking, it involves larning to utilize detectors, Peripheral Interface Controllers and larning its programing every bit good.BACKGROUND LITERATUREA PIC microcontroller is use to move as a control Centre of the automaton as it has computation, entrepot and I/O maps. By utilizing PIC, C scheduling or throng linguistic communications accomplishments are required as microcontroller operations are based on the package programming to implement the undertakings. The PIC16F76 1 has been chosen as the microcontroller of this undertaking as it has several particular pins and characteristics that suits for this undertaking demands such asO PIC16F76 has a entire simulacrum of 28 pins. It is make up of three I/O ports ( Port A, B and C ) which has a 22 I/O pins in sum.O In I/O port A, there are five enter channels of 8-bit Analog-to-Digital faculty which chuck up the sponges transition of an parallel arousal signal to a corresponding 8-bit digital figure that is helpful in analysis the signal transmits from RF receiving system.O Two PWM ( Pulse Width Modulation ) get under ones skin/Compare pins those are good in control the velocity and on/off of the DC motor by puting PWM responsibility rhythm.O SCL and SDA pins offer pass on with supersonic straight.An supersonic is a type of detector that uses to bring forth high frequence ( above 20 kilocycle per second ) sound wave pulsations and detects an object by construing the reverberations signal from its sound sorrowful ridge pulsation. The sound moving ridge pulsations are going in one way, when it detects an object, the echoed signal will be reflected back to the transducer of the supersonic detector. The scope from detector to object is able to find by ciphering the continuance of snippet between the comminuted the sound wave pulse detects the object and hab ilitate for the echoed signal to return back to detector. When detector detects an object, it will trip a signal and sends it to PIC.Supersonic detector is good in observing liquids, panoptical objects and irregularly molded objects. Therefore, it has been chosen to move as an obstruction sensor of this undertaking instead than other detectors. Besides that, supersonic detector has a higher sensing scope and the reflected signal does non affected by the issue and colour of objects. The supersonic detector SRF08 2 is a high macrocosm presentation supersonic scope finder with a scope from 3cm to 6m. The communicating between SRF08 with microcontroller is via I2C coach. The I2C coach consists of 2 busy wires and a land. Bi-directional SDA and SCL are the active coachs. SDA is Serial Data agate line and SCL is Consecutive Clock line, both of them hold up a pull-up resistance to +5v someplace on I2C coach. SRF08 is ever a slave neer a coach maestro.For the wireless frequence remo te control, the wireless wave signal can go through rough or through the object, such as wood, glass, walls and other stuffs. The advantages of utilizing wireless frequence remote control are, signal transmits range farther than infrared distant control and signal does non necessitate to be transmitted in line to receiver. The disadvantage of utilizing wireless moving ridges to convey signal is, signal will be affected by the presence electromagnetic intervention in the environment. A RF faculty 3 ( TWS-434 and RWS-434 ) has transmitter frequence 433.92 megacycle when it end crop is 8mW with a scope of about 200 understructure for indoors and 400 pes for out-of-doorss. It is ability to accept both digital and analogue inputs. Operating electromotive force is 1.5 to 12 volts-DC. For the RWS-434 receiving system, it is besides operates at the equivalent frequence which is 433.92 MHz and a sensitiveness of 3uV. The receiving system has both additive and digital end products and trial set outing electromotive force from 4.5 to 5.5 volts-DC supply.Two DC gear motors are installed on the automaton platform as the motor thrusts ( wheels of automaton ) . The EMG30 4 motor is a DC motor with encoder. Encoder is used to tracking the figure of revolutions and the place of motor. The rated electromotive force of this motor is 12v. These are the characteristics of EMG30 DC motorO No burden velocity 216 revolutions per minuteO No fill current 150 maO Rated torsion 1.5 kg/cmO Rated current 530 maO Rated velocity 170 revolutions per minuteO Rated end product 4.22 WThe motor shaft can be rotated in ii waies that clockwise or counter-clockwise way. Therefore, the automaton moves frontward or rearward merely inversing the mutual opposition of the situation supply of the DC motor. The turning operation makes by holding two wheels turning in different waies at the very(prenominal) time. This motor has anteroom detectors 5 every bit good. A hall detector varies i ts end product electromotive force in response to alterations in magnetic field, it used for placement and velocity sensing applications of this undertaking.An H-bridge is a cardinal shift elements device which enables a electromotive force to be applied across the motor or burden in merely one way. It is utilizing to move as a motor control band that allow DC motor to run forwards and backwards by providing the electromotive force to different switches. An H-bridge is built with four switches. When the switches S1 and S4 are closed, S2 and S3 are unfastened a positive electromotive force will be applied across the motor. The electromotive force will be in the reversed way by opening S1 and S4 switches, shuting S2 and S3 switches. The H-bridge is by and large used to change by reversal the mutual opposition of the motor, but it can be besides used to halt the motor or to allow the motor run freely. Switches S1 and S2 or S3 and S4 should non be closed at the analogous clip as it w ill do a short turn on the input electromotive force. L298 6 is a high electromotive force and high current double full-bridge driver. The chief intent of L298 is to move as a motor accountant to command the rotate way of DC motor harmonizing to the end product electromotive force from PIC.It is taken from mention of H-bridges Theory and approach pattern , available from hypertext transportationence protocol //www.mcmanis.com/chuck/robotics/tutorial/h-bridge/S1S2S3S4Motions of the motor1001Motor moves right0110Motor moves left0000Motor free tallies0101Motor brakes1010Motor brakesWORK doIn the past few hebdomads, a batch of consideration and enquiry undertakings have been done. For illustration, the extension incur of wireless frequence, and besides the working rule of H-bridge motor control and PWM. Some tutorials that helpful and related to the PIC scheduling have been read as good. On the other manus, all the constituents of this undertaking have been decided after rea ding the datasheets of each constituent. At the same clip, automaton platform has been intentional and sent to the mechanical s workshop in order to cut metal home base into the designed form. Furthermore, the pin connexions between the PIC, detectors and motors have been decided after reading datasheets of constituents and PIC. So far, the advancement of this undertaking is on the measure of circuit conventional conniving and larning the package scheduling of PIC undertakings. crepuscule 1 Seriess connected with a 10kI resistance to +5v DC supply.Pins 2 &038 A 3 block up product ports for LEDs.Pins 5 &038 A 7 to move as inputs from shaft encodes of motor.Pin 8 marry to land.Pin 9 &038 A 10 Connect to a parallel crystal 4 MHz and two serial publication 33 pF capacitances with land.Pins 12 &038 A 13 PWM outputs connect to the H-bridge.Pins 14 &038 A 15 I/O ports of I2C lines connect to the supersonic detectors.Pin 18 End product port for doorbell.Pins 25 &038 A 26 End prod uct signals connect to H-bridge.Pins 21, 22, 23 and 24 Act as input ports from RF receiving system.Advancement AND PlanNow, it is on the measure of larning package scheduling and circuit conventional designing undertakings, but it is a small spot hold up due to the clip disbursement on the undertaking less than undertaking program for past few hebdomads, since I was busy in fashioning other faculty s assignments and could non make up ones mind the constituents on clip.On the following semester, the clip disbursement on this undertaking will be more than the novice program in order to gimp up the advancement that has been planned as undertaking program. These are the major(ip) undertakings that will transport out consequently on the undermentioned semester1. RF faculty proving.2. Supersonic faculty testing.3. DC motor testing.4. PCB circuit design.5. PCB etching and soldering of constituents.6. Prototype theoretical account building.7. Trial and seek run the automaton system to m odify the scheduling of PIC.8. Troubleshooting and debugging.9. Test overall functionality.On the undermentioned semester, the clip disbursement on making this undertaking will be 18 hours per hebdomad.The item agenda of this undertaking has been shown on the Gantt chart.List OF rootageBookDEVENDRA K. MISRA, Radio-Frequency and Microwave Communication Circuits , Printed in the unify States of America, By fundament Wiley &038 A Sons, Inc, 2001.Newton C. Braga, Roboticss, Mechatronics, and Artificial Intelligence, Experimental Circuit Blocks for Designers , Printed in the United States of America, By Newnes Boston Oxford Auckland Johannesburg Melbourne New Delhi, 2002.InternetRichard J. Valentine, Motor Control Electronics Handbook , Printed in the United States of America, The McGraw-Hill Companies, Inc. , accessed by 30th October 2009, E-book, available fromhypertext transfer protocol //books.google.com/books? id=kLZL5hTsVIYC &038 A printsec=frontcover &038 A source=gbs_ navlinks_s v=onepage &038 A q= &038 A f= imitationJim Brown, Brief H-BRIDGE THEORY OF OPERATION , Written at April 1998, accessed by inaugural November 2009, available from hypertext transfer protocol //www.dprg.org/tutorials/1998-04a/Chuck McManis, H-bridges Theory and Practice , accessed by 1st November 2009, available from hypertext transfer protocol //www.mcmanis.com/chuck/robotics/tutorial/h-bridge/Milan Verle, PIC Microcontrollers , mikroElektronika 1st edition, Written at 2008, accessed by 25th November 2009, available from hypertext transfer protocol //www.mikroe.com/en/books/picmcubook/ch5/Nebojsa Matic, Programing PIC Microcontroller in BASIC , mikroElektronika, Chapter 6 PWM Module, accessed by 1st December 2009, available from hypertext transfer protocol //www.mikroe.com/en/books/picbasicbook/06.htm 6.5Chuck McManis, H-bridges Theory and Practice , accessed by 1st November 2009, available from hypertext transfer protocol //www.mcmanis.com/chuck/robotics/t utorial/h-bridge/Bibliography 1 PIC16F7X Data Sheet28/40-Pin, 8-bit CMOS FLASH Microcontroller, By Microchip Technology, Inc. , 2002.hypertext transfer protocol //ww1.microchip.com/downloads/en/DeviceDoc/30325b.pdf 2 SRF08 High Performance Ultrasonic Range Finder, By Acroname, Inc. , 1994-2009.hypertext transfer protocol //www.acroname.com/robotics/parts/R145-SRF08.htmlhypertext transfer protocol //www.robot-electronics.co.uk/htm/srf08tech.shtml 3 Radio Frequency Module ( TWS-434 and RWS-434 ) Data Sheet, By Rentron Electronic.hypertext transfer protocol //www.rentron.com/Files/rf.pdf 4 DC Gear motor ( EMG 30 ) Data Sheet, By technonots.co.uk.hypertext transfer protocol //www.technobots.co.uk/acatalog/info_1453_005.html 5 Hall Sensor Principles, By Honeywell.com.hypertext transfer protocol //content.honeywell.com/sensing/prodinfo/solidstate/technical/chapter2.pdf 6 L298 H-Bridge Data Sheet, By STMicroelectronics.hypertext transfer protocol //www.st.com/stonline/products/ liter ature/ds/1773.pdf