Cart Safety Review

Cart Safety Review

Hazards and mitigating efforts

• Rotational Motion

1. Possibility that someone could be hit by system while it is under remote control
   1. There are drive power kill switches located next to the two access points for the alcove. If the buttons are pressed the AC power is cut to the drive system. This power can only be restored by resetting the switch and pressing a safety restore button on the cart.
   2. The system moves slowly so you can easily walk out of the way.
   3. Under normal operation the cart would only move when the hall is locked up.
   4. During calibration of the drive system someone will be standing next to the cart.
   5. During remote operation of the cart someone must watch the system on camera.

• Moving the carriage

1. The carriage is manually positioned and requires more than one person to move it. One can push it, but by SOP a second person must be there to watch for problems.
   1. The system has stops built in so that it cannot fall off of the rollers.
   2. You might be able to push the carriage past center and the cart might tip over.
      1. To mitigate this possibility the outrigger wheels are mounted in their second position on the right. This mechanically constrains the carriage so that it cannot be put in an unstable configuration.
      2. If another configuration is needed all constraints can be moved to their mirror position on the opposite side.

• Moving the cart

1. Moving from the platform position to the alcove position could cause strain.
   1. Two people are necessary to maneuver the cart.
   2. The cart does not transition floor levels.
      1. Steel has been added to make the two positions all on the same level
2. Moving the cart could tip the cart over.
   1. The carriage must be in the rolling position and locked before motion starts. This places some of the load on the outrigger making it more stable.
   2. During testing the cart was found to be very stable while moving it with 125% load.

• Drive System Hazards

1. By its nature the drive system can pinch or crush fingers if they are stuck into the system while it is energized.
   1. There is a safety cage surrounding the open or pinching portions of the chain drive.
   2. All work performed on the drive system while the cover is removed must be in a power off condition.
2. The drive can start and stop with no visible operator.
   1. Drive power kill switches are provided.
   2. If the CAMAC crate is powdered down the computer also cannot move the system.
   3. The computer is password protected to prevent unauthorized use.
3. People that are working on the system will be made aware of pinch point areas through an orientation.

• Shock Hazards

1. Care has been taken to shield all electrical connections
2. Systems built at IU are sealed shut with screws requiring tools to open to keep unauthorized people out.
3. All other systems are assembled as the manufacturer recommends or with the equipment they supplied. In one case additional shielding was added to a transformer to prevent accidental access.
4. Everything plugs into 1 power strip. If there is ever a concern, the entire electrical system on the cart can be rendered dead by unplugging this one cord.