Motors_Servos_PWM - Sep-7-102:32 PM EEL-5666: Intelligent...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Sep-7-10—2:32 PM EEL-5666: Intelligent Machines Design Lab University of Florida, EEL 5666 © Drs. A. A. Arroyo & E. M. Schwartz 1 Today’s Menu • DC Motors • Servos • Stepper Motors • Pulse-Width Modulation • Solenoids EEL-5666: Intelligent Machines Design Lab University of Florida, EEL 5666 © Drs. A. A. Arroyo & E. M. Schwartz 2 Electric Motors • An electric motor converts electrical into mechanical energy. > Motors come in all manner of shapes and sizes. – There are electromagnetic direct current (DC) motors and electromagnetic alternating current (AC) motors and multiple variations of each. > AC motors are typically used for large machinery (such as washers, dryers, machine tools, A/C units and the like) and are powered from an AC power source. – AC motors have such titles as single-phase, split-phase, capacitor start, and three-phase motors, to name a few. – AC motors are seldom used in our robots because a mobile robot’s power supply is typically a DC battery or battery pack. > DC motors appear in a large variety of shapes and sizes: – Permanent magnet iron core, permanent magnet ironless rotor, permanent magnet brushless, permanent magnet stepper, and hybrid stepper
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sep-7-10—2:32 PM EEL-5666: Intelligent Machines Design Lab University of Florida, EEL 5666 © Drs. A. A. Arroyo & E. M. Schwartz 3 DC Motors • For robotic purposes, a DC motor usually runs at too high a speed and too low a torque. > In order to swap these characteristics, they must be geared down. > Connecting the shaft of a motor to a gear-train causes the output of the shaft from the gear-train to rotate much more slowly and to deliver significantly more torque than the input shaft. • DC motors can be purchased with the gear-train already prepackaged inside the motor housing. They are called DC gear-head motors and are normally based on permanent magnet ironless rotor motors in order to be as lightweight as possible. EEL-5666: Intelligent Machines Design Lab University of Florida, EEL 5666 © Drs. A. A. Arroyo & E. M. Schwartz 4 DC Motors • DC Motor Rotation > Most DC motors have two electrical terminals. Applying a voltage across these two terminals will cause the motor to spin in one direction, while a reverse polarity voltage will cause it to spin in the other direction. The amplitude of the voltage determines the motor speed. Polarity direction Amplitude speed > Stepper motors have six to eight terminals. Signals applied to these wires energize different coils inside the motor sequentially. The rotor is subsequently attracted to each portion and “stepped around” in a continuous fashion. The timing of these signals determines the motor speed, the phase between signals determines direction, and the number of wires determines the motor position.
Background image of page 2
Sep-7-10—2:32 PM EEL-5666: Intelligent Machines Design Lab University of Florida, EEL 5666 © Drs. A. A. Arroyo & E. M. Schwartz 5 Servo Motors • Servos > Servo motors, or servos for short,
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/11/2010 for the course EEE 5666 taught by Professor Scwartz during the Spring '10 term at University of Florida.

Page1 / 11

Motors_Servos_PWM - Sep-7-102:32 PM EEL-5666: Intelligent...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online