Digital position readouts (DROs) are almost a necessity for milling machines. The numerical display shows you the position of the machine elements, such as the X and Y position of the mill table and the Z-axis position of the cutting tool. Unfortunately, commercial DROs are expensive and bulky. Luckily, StudioBelow has a streamlined option with its new DRO for milling machines.
The three-axis DRO has all the essential features of commercial variants but is compact, measuring only 90mm x 150mm. Its polar coordinates mode offers a wide variety of tasks that are normally done by non-intuitive features on commercial devices. It also has selectable reference origins, which are more efficient than the standard ABS/INC feature of most DROs.
System configuration – axis sensors PPI, axis direction inversion, decimal points per unit – can be sent via serial using a GUI made for Windows or using a serial terminal. The data is stored in non-volatile memory.
- Eight 0.56" digits display per axis
- Quadrature optical encoders interface (RJ11 sockets)
- Two independent reference origins
- Axis zeroing per origin
- mm/inch units
- Cartesian/Polar coordinate system representation
- 50 points memory
- Encoders input filtering
- Recalculation of display values at 25Hz rate
- Built as a shield for the Arduino Uno
- Adjustable display brightness
- Hardware encoder signals XORing for more accurate interrupts utilization
- Powerful MAX7219 display drivers
- Fast, optimized arithmetic manipulations for real-time polar coordinates conversion
For $160, you'll get the compact DRO, which comes with an assembled board including a pre-programmed MCU board. Seems alright to me. You'll have to supply your own 5V power supply though. Get all the details here.