The DomeControl hardware was designed to provide a Mac-friendly solution to the automation of a Sirius Home Dome, assuming that the Sirius manually-controlled motorisation option is already fitted. Sirius do offer computer-control of the dome rotation as an option, but this is based on a third-party electronics board with software for Windows only. This option also requires a small amount of hardware adaptation too, to provide for a means of counting revolutions of th motor drive shaft and for determining a known rotation position, normally called the home position.
The DomeControl hardware (also called MacDome Controller) is based on the following principles:
• use of a commercial proportional motor controller;
• use of a high-resolution optical encoder for position feedback;
• use of a magnet and Hall efect snesor for determining the home position;
• provision of a hand control box;
• provision of a height sensor, to adjust to the height of variable-height telescope piers.
These have been realised by using a powerful, intelligent motor control board originally intended for robotics. The prototype controller was based on an AX3500 board, and subsequent controllers are based on the smaller and cheaper SDC2130 board.
The Sirius Observatories website used to provide information on automation options, but unfortunately it has been downgraded and now provides little substantive content.
More technical information is available on the sites of some Sirius dealers:
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