Vex Robotics Design System's Inventor's Guide

MOTION

TABLE OF CONTENTS:
SQUAREBOOT ASSEMBLY
CONCEPTS TO UNDERSTAND
SUBSYSTEM INTERFACES
MOTION SUBSYSTEM INVENTORY

SQUAREBOOT ASSEMBLY

In the Squarebot design, the Motion Subsystem is tightly integrated with the Structure Subsystem. The two systems are built together to form the “Chassis” of the Squarebot.

Refer to the Squarebot Chassis Parts and Assembly section in the Structure chapter to see how the Motion and Structure subsystems are built in tandem.

CONCEPTS TO UNDERSTAND

Motors and Servomotors
Motors are devices that can transform electrical energy into mechanical energy. That is, they take electrical power, and create physical motion. In the VEX system, they are further divided into two main types: standard mo-tors and servomotors.

The main difference is very clear and straightforward. Standard motors spin the attached axle around and around, while servomotors turn the axle to face a specifi c direction within their range of motion (120 degrees for the Vex servo module).

Note also that the Vex motor modules and Vex servo modules rotate their shafts in opposite directions, given the same transmitter command. This minor difference is due to the internal motor designs of the two different modules. For more information on radio control operation, see the Control Subsystem section of the Inventor’s Guide.

Using Motors and Servos
While similar in appearance, motors and servomotors are suited to distinctly different types of tasks.

Regular motors should be used whenever continuous rotation is needed, such as in a robot’s main drive system.

Servomotors can only be used in cases where the boundaries of motion are well-defi ned, but have the invaluable ability to self-correct to maintain any specifi c position within those boundaries.