wolfvierbergen
Focus-mechanism
A focus mechanism for a thermal camera.
The mechanism turns a lens of a thermal camera and keeps it’s absolute position.
Description
The focus mechanism consists of a belt drive that turns the lens of a thermal camera. The main component is a stepper motor, a Nema 14 with dual axis:
- the front axis is used to turn a belt mechanism connected to the lens.
- The back axis is connected to a multi turn potentiometer, this is necessary for the absolute position control.
Hardware
• Arduino Uno
• DRV8825 stepper driver
• Nema 14 (dual axis)
• Mosaic core 9.1mm lens core
Firmware
• FocusmechanismV2.ino
Executing program
• Open the serial monitor
• It will show the current position on a scale of 1-1000
• For a new position: write a new value between 1-1000
• The stepper motor will move until the potentiometer matches with the input
Version History
• V1 (11/2022): Gear mechanism
• V2 (12/2022): Belt drive