The Interface communicate to DC motor control

Abstract

Mälardalens University makes internationally recognized research in the field of Robotics. This technological work shows an electrical engine control developed at Mälardalens University. The target of this project is to make an interface able to communicate with a platform/robot to move the platform/robot using an electric engine control in ADA language. There are different kinds of electric engines, AC, DC, stepper motor, etc. This control focuses on DC electric motors because they are typically used in robots. The control works with a PWM system (Pulse Width Modulation). As its name says, this system consists in sending pulses (high-low), obtaining this way a periodic square wave. This signal can modify the duty cycle, i.e. to change the duration of the high level or the low level as well as varying the frequency of the signal. There is a huge variety of types of Integrated Microcontrollers that can deliver PWM signals according to their characteristics. One of them is the ATmega128, which has incorporated an H-Bridges to turn forward or reverse trough the PWM signal output. The control of the DC motors consist in sending a signal through the H-Bridge devices, that makes the motors works either together, or only the left or the right one or stop both of them. This signal is of the type PWM (Pulse Width Modulation), which can control the output, the length of the wave, the frequency, etc.