CLOSED LOOP MOTOR CONTROL USINGAHRSBYESHAAN KUMARTEJAS SSHILPA SUnderthe Guidance ofINTERNAL GUIDE EXTERNAL GUIDEMrs. Padmaja Vijaykumar Mr. R. SrinivasanDepartment of ECE, AIeMS SC ‘F’, ADE, DRDO
AHRS Gyros are used world wide in UAV’s Gyros are nothing but devices which measuresrate of rotation of an Object in Space. Traditional Gyros are Huge and Bulk andRequires a large maintenance Cost as it ispurely Mechanical. AHRS can eventually replace these traditionalGyros.Typical MechanicalGyroscopes
Introduction of AHRS eventually lead to thereplacement of Traditional Gyros.AHRS is an IMU used for measuring the positionof an object in Space.AHRS Contains Accelerometer, Gyro meter andmagnetometers(17 bit)Typical AHRS
AHRS is an 32 bit high performance processorwhich measure parameter like Euler angles andEuler rate.AHRS Provides Digital data and o/p are based on type of CommandAHRS Configurations: (Serial portconfiguration, baud rate, start bit ,stop bit, parity)Principle axis of Rotation of an Aircraft
Design an Closed Loop Motor Control systemwhich makes use of ADuC 7020 microcontroller along with AHRS for every ~5ms. Use the Roll data and Roll rate in order tocontrol the motor. Provide an appropriate Signal conditioningcircuit(hardware design) which is sufficient tocontrol the motor Also provide an user interface to change thecommand using 3-bit parallelport(8commands)
Function: The3DM-GX3™ will output a data record containing EulerAngles and Angular Rates.Command:Byte1 0xCFFunction: The3DM-GX3™ will output a data record containing EulerAnglesand AngularRates.Response:Byte1 0xCFBytes2-5 Roll (IEEE-754Floating Point)Bytes6-9 Pitch (IEEE-754Floating Point)Bytes10-13 Yaw (IEEE-754Floating Point)Bytes14-17 AngRateX (IEEE-754Floating Point)Bytes18-21 AngRateY (IEEE-754Floating Point)Bytes22-25 AngRateZ (IEEE-754Floating Point)Bytes26-29 TimerBytes30-31 Checksum
µC is required because1. One Serial RS 232 interface - For AHRS2. 3 – bit parallel port interface to set the rollcommand3. DAC
The roll output of the AHRS on DAC for a step command of +157 deg
The roll output of the AHRS on DAC for a step command of -45 deg
AHRS is proved to be a useful element to beused in UAVs. Designed system gives the update value fromAHRS for every ~5ms. System designed provides Steering andStabilization mechanism.
A successful attempt was made to design aclosed loop control system using availablemotor with AHRS. This project has also demonstrated itsperformance in using in any steering andstabilization system in space. The line of sight of motor remains the sameirrespective of the rotating motor .