Robot States

The SER-CAT sample mounting robots are based on the ALS style automounter. The systems are comprised of 2 independent motions: gripper and dewar. The gripper motions are pneumatic and move samples back and forth between the dewar and goniometer. The dewar motions are motor driven and place the dewar in the correct sample position for mounting/dismounting both samples and pucks. A user will not normally need to know anything about the dewar positioning system (except for loading/unloading pucks), but the gripper motions are easily identified and it is useful for a user to understand where the gripper should be.

Gripper

The gripper is the working end of the robot that moves your samples between the dewar and goniometer and is shown in its idle state below.

The gripper motions are pneumatically driven, so each motion can be in 1 of 3 conditions: extended, retracted or moving. For the purpose of this discussion, we will only be concerned with a motions extended or retracted conditions or states. During normal operations, the gripper will be in 1 4 defined states: idle, dewar, goni and defrost. The state of the gripper can be viewed by the hutch camera display (video 3 for remote users).

Idle

The idle position is when all of the pneumatics are retracted and the gripper is in its ready position. The idle position is where the gripper is placed when not in use or after a defrost cycle.

22BM gripper in idle position indicated by circle.

Dewar

During normal operation, the gripper will spend a lot of time in the dewar waiting cold to mount the next sample.

22ID gripper in dewar position

22BM gripper in dewar position

Goni

The gnoi state a transient state used to mount/dismount samples from the goniometer. The gripper only spends about 1 second in the goni state during each mount/dismount.

22ID gripper in goni position

Defrost

The defrost state is used to warm up the gripper. During normal use, the gripper will accumulate ice and must be periodically warmed up to remove this ice. The control system will automatically defrost the gripper after 12 mounts/dismount or when a data set has been initiated from the sergui collect_runs page.

22ID gripper in defrost

22BM gripper in defrost

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