Last updated: 10-22-99

Project: DEIMOS
Stage: Grating Rotator, Position #1, Side A
ID #: KDGC-001A
Engineer: J. Osborne

Mechanical Description of Stage: Rotates 8" X 12" (large) grating or 6" X 8" (small) grating. Tilt angle is maintained when other grating rotators move into position. (e.g. no "home" position.)

 

Electronic Description of Stage:

 

Required setting accuracy : Sub arc-second!

Accuracy and resolution requirements:

Performance requirements and design goals
Component Requirements 1
Motors: Galil 50-1000 3750 RPM / 205 in-oz peak stall torque
Limits 2: Microswitch BZ-2RW822-A2 "soft" + DT-2RV22-A7 "hard" -
Fiducials: Opto-interupter TRW #OPB-970-T55 (Optical) -
Encoders: Gurley 8335-11250-CB-S-A -
Air Cylinders: None -
Air Solenoids: None -
Lock/Clamp/Brake: None -
Interlocks: Lockout during manual installation of new grating (see lockout schedule) -
  1. Speed, temperature, accuracies, electrical power, pressurized air, lubricant, coolant, N2 purge, ...
  2. Primary (inner) and secondary (outer) limits. These can be magnetic, optical, or physical contact
NOTES: -20 degrees C needed. Galil BEI motor encoder only rated -10 degrees C, but we have tested them. They are OK.
Manufacturer's specifications and limitations
Component Maximum Operating Condition  Safe Ops Condition  Requirements 
Motors: - - -
Limits: - - -
Fiducials: - - -
Encoders: - - -
Air Cylinders: - - -
Air Solenoids: - - -
Lock/Clamp/Brake: - - -

Final Mechanical Assembly and Testing Results

Tests performed by:

 
Motor tuning parameters under different spacial orientations and environment
Parameter    Neutral Gravity  Uphill 1 Downhill  Cold  Cold Uphill 
Motor Type: - - - - - -
PID Filter: KD: - - - - -
KP: - - - - -
KI: - - - - -
Acceleration (pulses/sec^2): - - - - - -
Deceleration (pulses/sec^2): - - - - - -
Speed: - - - - - -
Other: - - - - - -
  1. Uphill defined as motor (or driven end of shaft) in lowest position

Motion Parameters

Rotary Stage (constrained)
Distance from "home"  Position Motor Counts  Physical Units Time to Reach
Primary (inner) Limits:  Forward - 22 degrees from center -
Reverse - 23 degrees from center -
Secondary (outer) Limits:  Forward - 23 degrees from center -
Reverse - 24 degrees from center -
Position # None (any posn available) 1 - - -
2 - - -
3 - - -
4 - - -
5 - - -
6 - - -
1 revolution CW - - -
CCW - - -
Resolution of Stage
Encoder Counts/Inch Counts/Millimeter Counts/Degree
On Motor (BEI) 4000 counts/motor rev - 5215 
On Stage (GURLEY *) - - 2500

NOTES:

Mechanical Drawing(s) # d45xx series

Electronic Drawing(s) #EL-3058 and EL-3059

Sign conventions are such that a positive motion of the motor turns the motor in a CW direction as viewed from the drive shaft looking back into the motor, and will drive the stage towards the forward limit.