Atmospheric Emitted Radiance Interferometer AERI

Symptoms

AERI Ingest isn’t able to run. FTSW logs return messages (see Fig. 1):

Mirror controller Error, Impossible to set pointing mirror on position 1344 Actual position = 446
Mirror controller Error, Error SerialConnectionException : com.bomem.aries.console.acquisiton.PointingMirrorController$SerialConnectionException: No response on Request

Warning

Always power OFF the AERI before disconnecting any of the mirror/motor subsystem wiring. Otherwise the components can get damaged.

Troubleshooting

Look for any fault lights on the motor controller

Test for physical obstructions in the rotation of the mirror drum:

• Power OFF the AERI. Remove the circular nadir port cover at the bottom of the ‘hex’ using the 4x thumb screws. Rotate the drum in both directions and check if it rotates freely.
• Remove the mirror/motor assembly (held on by 4x #10 socket head cap screws, see Fig. 2). Look for foreign objects around drum and inside the hex; look for deformation or scratches on the mirror drum. Make sure the drum turns easily
• Try running Ingest with the mirror/motor assembly removed, to determine whether the issue is with the hex or the mirror drum (for the M-AERI).

Swap out components

1. Mirror/motor assembly (Fig. 3):
   • Power OFF AERI
   • Disconnect the four cables going to the assembly (MOTOR, ENCODER, MO TEMP / PE TEMP, S MIRROR)
   • Remove the assembly using the 4x #10 socket head cap screws (Fig. 2)
   • Swap in a new assembly
   • Replace the 4x #10 socket head cap screws. Be sure to push the assembly upwards prior to tightening, so that the surfaces get registered upwards for optical alignment.
   • Reconnect the four cables
   • Power ON the AERI and test for functionality
2. Controller (Fig. 4):
   • Take a photo of the connectors on the back of the motor controller
   • Power OFF the AERI
   • Remove all the cables going to the motor controller (power cable, motor encoder, motor power, there’s also thermistor usually mounted to the top surface)
   • Remove the motor controller: loosen the two screws holding it to the wall on the bottom; remove the single screw holding it to the wall on the top, then remove the controller
   • Swap in a new controller
   • Replace/tighten the 3 screws holding it to the wall.
   • Replace all the cables going to the motor controller in the identical configuration as before
   • Power ON the AERI and test for functionality
3. Cables. It’s unlikely that these got damaged, but they can be swapped out as well:
   • Take a photo of the connector on the back of the motor controller
   • Power OFF the AERI
   • Remove the cables going between the mirror/motor assembly and the motor controller (motor power and motor encoder). Disconnect the MOTOR and ENCODER cables on the mirror/motor assembly on the front-end side. Disconnect the other ends of those cables attached to the motor controller on the back-end side. Remove the cables from the tube.
   • Swap in the new cables, feeding them through the tube, and connecting the respective sides
   • Power ON the AERI and test for functionality