INDI Arduino Cap

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Summary

INDI Arduino Cap is a dust cap 'driver' compatible with INDI and EKOS, that uses the python library pyfirmata. Arduino Cap uses an Arduino with the StandardFirmata firmware. This will work with a 'rc style' servo on any of the digital PWM outputs. Most servos is 4.8v-7.4v and a old phone charger or similar would work as a powersupply. If you use a servo that is not 4.8v then change powersupply accordingly.

You can also (optionally) install USBRelay2 Roof, and use a relay channel as a (fixed/undimmable) lightsource.

Attributions

• This project could not be done without the existing INDIlib project or the pyFirmata interface and standard firmata arduino firmware.
• This project is 3rd party and dependent on the mentioned projects, and licensed accordingly. See LICENSE and COPYING.BSD.
• Some files have additional lisence information, see file headers.

Installing dependencies

1. INDILib, and it's dependencies

   • To build libindi from source see instructions on indilib.org

2. PyFirmata, and it's dependencies

   • To install pyFirmata see this page on pypi.org

3. (Optional) INDI USBRelay2 Roof, and it's dependencies

   • To build USBRelay2 Roof from source see instructions on github

Install INDI Arduino Cap

• Install

  $ cd ~/Projects
  $ git clone https://github.com/magnue/indi_arduino_cap.git
  $ mkdir -p build/indi_arduino_cap
  $ cd build/indi_arduino_cap
  $ cmake -DCMAKE_INSTALL_PREFIX=/usr . ../../indi_arduino_cap/
  $ sudo make install
  

• Update

  $ cd ~/Projects/indi_arduino_cap/
  $ git pull
  $ cd ../build/indi_arduino_cap
  $ sudo make install
  

Screenshots

Calibrate

• Configure Servo ID, Flat Light device, calibrate travel limits, prefered limits, and optionally reverse servo direction.
• To configure a USBRelay2 channel for light source, make sure atleast one Power device is added to the "Device Setup Tab" of USBRelay2 Roof. Take a note of the "dev x" number. In ServoBlaster Cap's "Calibrate tab", set "Flat light device" to "x", and make sure Light Device is set to "use USBRelay2" in ServoBlaster's "Options Tab".

Main Control

• Not much to it. Parked = closed, UnParked = open - ready to image.
• Parking Cap will turn off lightsource, and lightsource can only be operated when Cap is unparked.
• To find Max travel limits, use 'step to (degree)' starting at 40, then decreasing until servo does not move any more. This is your close limit. Then set a value of 120 and increase until the servo does not move any more. This is your open limit.
• If servo is moving the wrong direction for the cap to close on park, and open on unpark, then swap one max travellimit for the other, in calibration tab.
• When installing cap for the first time, then set close limit to ~70%, then park. If the cap is not fully closed on the scope, then increase the limit to ~75% and unpark - park. Continue incrementing this until the cap is fully closed on the scope, and you have your preffered close limit.
• If you want the cap only to open to 70% of the open limit, set Prefered limit open to 70%.