The objective when designing a 4 axis stepper driver for a metal cutting machine manufacturer were to reduce the overall cost of the machine control, improve the reliability and serviceability of the control, provide advanced connectivity for communications, and improve the operating speed and performance of the machine.

The situation:
Tracker CNC manufactures fully automated computer controlled metal cutting machines. The control unit consists of a standard PC and a custom built stepper motor control and machine interface.

The problem: 
Tracker was using a control device with a combination of off-the-shelf and custom built components, including 4 individual stepper motor drives, a custom made interface board, various switches, relays and indicators, connected together with a complex wiring harness that had to be manually assembled and terminated as each machine was built.

Since the units are intended for use in harsh industrial environments, problems occasionally arose due to the presence of metal chips or dust, and vibration. When a problem occurred, Tracker and their customer had to troubleshoot to identify the specific component failure (stepper drive, control board, terminal connection), then disconnect and remove the failed device and install the appropriate replacement.

The initial characteristics that Tracker sought to improve upon:
• High cost of individual components and parts
• Complex and time consuming (costly) wiring harness
• Multiple voltage DC power supply requirement
• Requirement that the HMI be equipped with a parallel port
• Reliability problems
• Difficult to service

The solution:
OES developed a 4 axis stepper motor driver and controller for this specific application. All of the individual components (switches, LEDs, relays, etc.) were designed on a single board, completely eliminating the interconnection wiring harness – which removed most points of failure. The design also eliminated the need for multiple DC voltages, and increased the working voltage to the stepper motors. Quick-connect terminal blocks were used for all connections, simplifying installation and removal (if necessary). OES also chose to use .093” circuit board material (instead of the standard .060”), and conformal coated the final assembly in order to prevent contamination problems associated with the working environment. Because the power supply could now be optimized for the stepper motor control, the torque and speed of the motors also improved.

The result:
• Reduced component cost.
• Eliminated complex wiring harness (saving cost and assembly time).
• Improved power supply (at lower cost).
• Improved communications and connectivity through USB.
• Significantly improved reliability.
• Significantly improved serviceability.
• And, improved machine performance!

Summary:
The 4 axis stepper driver and controller solution from OES Technologies significantly reduces the over all cost of the machine control, greatly improves the reliability and serviceability, and improves the operating speed and performance of the machine.

To view videos of Tracker CNC Cutting Systems driven by the stepper drive control system from OES, Click Here.