The aim of this project is to obtain
linear and nonlinear models of Brushed DC motors, Brushless DC motors(BLDC), Permanent Magnet Synchronous
motors (PMSM) and AC Induction motors.
Currently, a simple test stand have been implemented
to obtain the linear model of DC Brushed motors. This test stand consists
of a Pololu
MC33926 Motor Driver Carrier, a small protoboard, a quad 2-input NAND gate
IC 74LS00, a National Instrument Low-Cost M Series Multifunction Data
The DC motor shown in the figure has an Optical Quadrature Encoder
with 300 PPR (pulses per revolution) and a gear ratio of
30:1., 200RPM, 12 V.
A LabVIEW vi have been developed to record the speed response when the duty cycle of the H-Bridge connected to the motor is varied randomly. The PWM signal has a frequency of 20 KHz. The duty cycle was allowed to vary from about 10% to 100%. Next picture presents the Front Panel of the LabVIEW vi.
The corresponding Block Diagram is presented next
The random duty cycle signal generated and the output response (encoder's frequency) were saved to a file. After this, the data was imported to MATLAB and processed using the free available University of Newcastle Identification Toolbox (UNIT). The discrete-time DC Motor Speed model obtained with the UNIT is an ARX (Autoregressive Exogenous) with the following structure
Next, some of the analysis plots, displayed by UNIT during the identification process, are presented
The discrete-time model obtained is shown next:
The ultimate goal of this project is to develop a robot for "surveillance" capable of completely autonomous operation, capable of 24/7
service. GPS capabilities and a videlo link will be included in the robot. The main computer will be running Ubuntu and the guidance, navigation and control system is expected to be implemented
using the Robot Operating System (ROS).
Next, we were testing that the robot was capable of manuevering while supporting the weight of the 100w solar panel (15lbs). This solar panel, under full sun linght, is capable of providing all the power needed for operating the computer, camera, video transmitter, microcontroller board, motors, and at the same time recharge the battery.
The goal of this project is to build an hexacopter. The frame has been built and is presented in the next figure