This low cost distributed motion controller system consists of two units: a USB-CAN converter and a dual axis controller. The USB-CAN converter uses the PIC18F258 and a FTDI FT245BM USB interface chip to translate messages between the USB and CAN buses. While PIC18F458-based dual axis controller is kept busy implementing servo/stepper trajectory and PID calculations every 500 usec to control 2.5A/phase stepper and a 2.5A DC servo.
Main features of the system:
- Easy wiring and setup – USB interface to PC, CAN (Controller Area Network) interface between nodes, single power supply, cage clamp connections, a Windows application for setup and motor tuning, boot loader for USB or CAN in-application updates of firmware. On-board 5V switching supply for +24V single supply operation. The USB-CANtastic board is bus powered. Standard 6-pin modular ICD2 jack for development and debug of custom software.
- Fully featured closed loop servo and open loop stepper motor control – high speed quadrature encoder interface, programmable PID control, trapezoidal motion profiles, 2KHz servo update, 1/8 microstepping, 50KHz step rate, built-in homing routines using opto-isolated limit/home inputs, programmable current limiting, position tracking error, settling window, real-time trace using CAN or 8K FRAM.
- Small size and cost – “PIC2UP”, a credit card sized dual axis controller with driver and “USB-CANtastic” and a very small USB-CAN converter (USD$20/100 for USB-CAN and USD$60/100 for PIC2UP). So USD$500 buys 16 axis controller and USB-CAN converter.