Drives and Controls Magazine
Motion controller works with brushed DC motors
Published:  15 August, 2013

The Californian controls company, Specialty Motions Inc (SMI), has developed a motion controller that provides variable speed control, direction control, and oscillating and jog-able motion, using standard 12V or 24V brushed DC motors. The D-Con controller is designed to be an low-cost and easy means of achieving such motion without needing to learn programming languages, or using expensive motors, complex drives, PLCs or computer controls.

DC motors are usually considered to be “dumb” machines that are not suitable for applications requiring sophisticated controls because they cannot accept commands and cannot provide reliable positional accuracy. However they are generally much cheaper than stepper or servo motors.

SMI’s controller works with almost any 12V or 24V brushed DC motor rated up to 10A. It can be used for single- or multi-axis applications, or for synchronous motion, and can be used with linear motion stages or slides fitted with suitable DC motors. No programming is needed.

The device uses PWM (pulse width modulation) to control the voltage output to the motor to provide variable speeds without adversely affecting the motor torque. The speed function is user accessible and adjustable.

The motion controller can be used to perform oscillating movements between home and limit sensors (contact or inductive), or can be operated by a joystick or other handheld controls.

SMI'c brushed DC motor controller

The device includes a two-stage variable speed function that is switchable on the fly. It can accept a joystick controller with a variable speed function via an RJ-45 port. It also accepts optional pushbutton controls for direction and speed.

An emergency-stop function is standard and a 5V output is available for optional outputs and sensors on both 12V and 24V versions. The DIN-rail-mounting controller includes LED indicators for power, fault and mode functions, as well as speed information.