specMech consists of the following hardware:
This wiring diagram shows how it is connected together.
The system is controlled by a Z-World Little Giant BL1100UM single-board programmable controller running Dynamic C32. Z-World's documentation:
The shutter and Hartmann screens are controlled by 6 air cylinders on a Clippard EMC-08 valve card. Each of the three devices is controlled by two air cylinders: one to open it, one to close it. The valves are driven by 12VDC and are rated at 0.67W (thus 0.056A holding current).
One valve for each device must be open at all times.
The collimator actuators are driven by a pair of Physik Instrumente C-808 motor controllers (each of which can control two axes). These are connected in parallel to one RS-232 port on the Little Giant. Documentation:
C-808 Operating Manual (scanned).
The PI C-808 is, unfortunately, a primitive controller. Limitations include:
DIP Switch S2 settings for SP2 are presumably identical to SP1, but they are hard to access so we are not sure. Certainly the limit switches are enabled and the baud rate ought to be the same.
The collimator mirror position is controlled by three M-222.20 actuators. The M-222.20 actuator is a compact, high resolution linear actuator consisting of a micrometer drive with non-rotating tip driven by a closed loop DC motor/gearhead combination with motor shaft mounted encoder. Documentation:
The allowed range of motion for our collimator mirrors is approximately 50,000 encoder counts, which is approximately 3 mm. Note that the actuator's full range of motion is 10 mm
Each spectrograph has two humidity sensors: Honeywell HIH-3605 or HIH-3610 (they are very similar and are read the same way) driven by 5VDC. See the source code for the assignment of which sensor goes to which input.
Each spectrograph has 5 temperature sensors: National Instruments LM35 driven by 5VDC (?). See the source code for the assignment of which sensor goes where.
The shutter and Hartmann screens each have two switch sensors: open and closed. Details unknown.
In addition, each collimator actuator has forward and reverse limit switches. Details unknown. However, as noted above, these are normally open (which is dangerous for limit switches) because the PI C-808 motor controller requires this.
