An INDI (http://indilib.org/) driver and arduino firmware to control a roll off roof of an astronomical observatory.
The roof is powered by a 550W electric hoist purchased from Aldi. The arduino controls 4 relays connected to the hoist's hand controller which override the manual switch. The indi driver comminicates with the arduino using the frimata protocol.
Hardware Parts List
- Electric hoist reworked to open and close the roof.
- Arduino Micro (to install firmware on)
- 4 X 30A relays http://www.dx.com/p/30a-250v-relay-module-red-blue-216873#.Vgg9-xNViko
- Project box (to contain arduino and relays)
- Linux machine running indi server (install the driver on).
Building / Installing Software
- Flash the firmware to your arduino using the arduino ide.
- Build and install the driver on the machine running indi server.
Wiring relays to the hoist switch
Relays were wired into the hoist's hand controller switch to allow both manual operation via the switch and operation from the arduino. WARNING: Never operate the switch using both the relays and manual switch at the same time as it may result in a 220v short circuit.
The photo below shows the hoist's hand controller switch with 6 numbered pins. The centre 2 pins (3 and 4) provide supply to either 1 and 2 or 5 and 6 depending on what way the switch is pressed. 4 relays were wired into this switch to override it.
The wiring diagram below shows the same switch on the right hand side. The centre shows the 4 relays and the left shows the arduino micro. The 2 limit switches are also shown attached to pins 8 and 9. See the arduino firmware sketch code for more details.
The photo below shows the finished enclosure containing the arduino and 4 relays.
- TODO: Photos of hoist in roof