This project aims to replace the manual tracking system which is part of the design of a home-built 2” x 72” industrial-grade belt grinder. This machine uses a 2-hp, 3-phase TEFC 220V motor, in combination with a VFD (variable frequency drive) to control speed, making this grinder suitable for bladesmithing and other blacksmithing operations which require metal removal. Each belt for this grinder is 2 inches wide by 72 inches long and has different tracking characteristics. Belts change in firmness and flexibility over time, stretching throughout use. This equates to tracking needing to be adjusted differently for each belt, and as a belt becomes worn that belt will track differently over time. This electronic tracking system will auto-adjust the tracking of a single axis, reducing the need for manual adjustments.

This electronic auto-tracking system seeks to solve this issue by self-adjusting 1 axis of the grinders tracking system. The project makes use of analog sensor input in the form of infrared beams reflected off the back of each belt (IR sensor). This analog value(0-5V) is then sent to an analog to digital converter (A/D) in the form of an Arduino micro-controller. The Arduino board (UNO Rev 3) utilizes a 10-bit A/D converter, taking the IR sensor voltage and converting that to a number between 0-1023. With this data in digital form, the Arduino has been programmed to make a decision on which direction the tracking axis needs to move. To accomplish this movement the Arduino is outputting digital control signals to a DM542T digital stepper driver. The DM542T takes input in the form of a pulse and direction inputs. These inputs control the speed of the stepper with a PWM signal at the pulse input and a high/low signal at the direction input. The digital stepper driver is powered by a DC power source (24-50V) and drives a NEMA 17 non-captive stepper motor. The motor in this case drives a screw and accomplishes linear movement of the tracking axis. With continuous feedback from the IR sensors, the belt position can be tracked automatically by the electronic tracking system as we have just described.