Pololu Jrk 21v3 USB Motor Controller with Feedback
#1392
The jrk 21v3 motor controller is a highly configurable brushed DC motor controller that supports four interface modes: USB, logic-level serial, analog voltage, and hobby radio control (RC). The controller can be used as an open-loop speed control or for closed-loop speed or position control. The continuous output current is approximately 3 A in the recommended operating range of 8-28 V, with derated performance down to 5 V and transient protection to 40 V.
Overview
The jrk 21v3 is a versatile, general-purpose motor controller that supports a variety of interfaces, including USB. The broad operating range from 5 V to 28 V and continuous output current of 3 A (5 A peak) allow this board to control most small DC brushed motors. Analog voltage and tachometer (frequency) feedback options allow quick implementation of closed-loop servo systems, and a free configuration utility (for Windows XP or Vista) allows easy calibration and configuration through the USB port.
Key improvements over competing products and earlier Pololu motor controllers with feedback include:
- USB connectivity with emulated serial (COM) port allows direct motor control from a PC.
- Ultrasonic PWM to eliminate switching-induced motor shaft hum or whine.
- Robust, high-speed communication protocol with user-configurable error condition response.
- High internal resolution (12 bits) for smooth and flexible calibration to various input and feedback devices.
- Current sensing and limiting.
- Reversed power protection.
- Field-upgradeable firmware.
Main Features of the Jrk 21v3
- Simple bidirectional control of one DC brush motor.
- 5 V to 28 V operating supply range.
- 3 A maximum continuous current output (5 A peak).
- Four communication or control options:
- USB interface for direct connection to a PC.
- Full-duplex, TTL-level asynchronous serial interface for direct connection to microcontrollers or other embedded controllers.
- Hobby radio control (RC) pulse width (PWM) interface for direct connection to an RC receiver or RC servo controller.
- 0-5 V analog voltage interface for direct connection to potentiometers and analog joysticks.
- Two closed-loop feedback options:
- 0-5 V analog voltage.
Frequency/tachometer digital input up to 2 MHz with 1 ms PID period.
(Open-loop control with no feedback also available.) - Simple configuration and calibration over USB with free configuration program (Windows XP and Vista compatible).
- Configurable parameters include:
- PID period and PID constants (feedback tuning parameters).
- Maximum current.
- Maximum duty cycle.
- Maximum acceleration.
- Error response.
- Input calibration (learning) for analog and RC control.
- Optional CRC error detection eliminates communication errors caused by noise or software faults.
- Reversed power protection.
- Field-upgradeable firmware.
- Optional feedback potentiometer disconnect detection.