Last updated: 2-5-02
Project: DEIMOS
Stage: Grating Tilt Stage #3
ID #: KDGC-003A
Engineer: J. Osborne
Mechanical Description of Stage:
6" X 8" grating rotator. Tilt angle is maintained even when out of position.
(e.g. no "Home"-ing is required.)
Electronic Description of Stage:
Driven by Galil Controller # 2, amplifier
2A - Axis B - requires EL-1272R #3 interconnect box.
This box has reversed wiring on JB5 so the Gurley counts in the same direction
as the motor encoder. This Gurley is mounted on the opposite side of the
grating. Slider translation position: -1,126,622
Required setting accuracy:
0.14 arc-seconds
Performance requirements and design goals
| Component |
Requirements 1 |
| Motors: Galil #50-1000 |
|
| Gearbox:- None |
|
| Limits 2: Microswitch BZ-RW822-A2 "primary" and DT-2RV22-A7
"secondary" |
|
| Fiducials: TRW #OPB-970-T55 (Optical) |
|
| Encoders: Gurley model 8335-11250-CBSA --- Serial # 960072 (900,000
Counts per Revolution) |
|
| Air Cylinders:- None |
|
| Air Solenoids:- None |
|
| Lock/Clamp/Brake:- Yes |
See KDGS-002A |
| Interlocks: See Lockout schedule |
|
-
Speed, temperature, accuracies, electrical power, pressurized air,
lubricant, coolant, N2 purge, ...
-
Primary (inner) and secondary (outer) limits. These can be magnetic,
optical, or physical contact
Manufacturer's specifications and limitations
| Component |
Maximum Operating Condition |
Safe Ops Condition |
Requirements |
| Motors: |
|
|
|
| Gearbox: |
|
|
|
| Limits: |
|
|
|
| Fiducials: |
|
|
|
| Encoders: |
|
|
|
| Air Cylinders: |
|
|
|
| Air Solenoids: |
|
|
|
| Lock/Clamp/Brake: |
|
|
|
Final Mechanical Assembly and Testing Results
Tests performed by: K. Dietsch 8-14-01, C. Harper 11-8-00
Motor tuning parameters under different spacial
orientations and environment
| Parameter |
|
Set |
| PID Filter: |
KD: |
289
|
| KP: |
58
|
| KI: |
33
|
| Acceleration (pulses/sec^2): |
|
256,000
|
| Deceleration (pulses/sec^2): |
|
256,000
|
| Speed (pulses/sec): |
|
25,000
|
| Set: CN 1,1 CB 2 |
|
|
Motion Parameters
Rotary Stage (constrained)
| Distance from "home" |
Position |
Motor Counts
|
Gurley Counts
|
Time to Reach
|
| Software Limits: |
Forward |
-
|
-
|
-
|
| Reverse |
-
|
-
|
-
|
| Total Rotation |
|
-
|
-
|
-
|
| Primary (inner) Limits: |
Forward |
+99,775
|
|
15 Seconds
|
| Reverse |
-847,588
|
|
35 Seconds
|
| Secondary (outer) Limits: |
Forward |
+101,844
|
|
17 Seconds
|
| Reverse |
-864,302
|
|
36 Seconds
|
| Defined Positions # |
1 |
-
|
-
|
-
|
| 2 |
-
|
-
|
-
|
| 3 |
-
|
-
|
-
|
| 4 |
-
|
-
|
-
|
| 5 |
-
|
-
|
-
|
| 6 |
-
|
-
|
-
|
| 1 revolution |
CW |
-
|
-
|
-
|
| CCW |
-
|
-
|
-
|
| Gurley Index Position |
|
+38,097
|
0
|
-
|
-
"Coarse" if from optical interrupter, "Fine" if from an encoder index
pulse. Home is defined as zero counts.
-
Primary limits signal the controller to stop motion. Secondary limits
cut motor power and require intervention to move out of them.
Resolution of Stage
| Encoder |
Counts/Inch |
Counts/Millimeter |
Counts/Degree |
| On Motor |
|
|
11.1
|
| On Gurley |
|
|
|
-
Gear reduction function: Two stages of friction drive plus timing belt
and sprocket: 923.9 X 60/24 = 2309.75
-
Gurley model 8335-11250-CBSA
-
Repeatability:
-
Fiducial:
-
Encoder:
-
Air Cylinders:
-
Air Solenoids:
NOTES:
Mechanical Drawing(s) #D4564
Electronic Drawing(s) #EL-3062 and EL-3063
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.