| 摘要 |
A method of determining drive roller scrubbing in a cargo power drive unit (PDU) comprises calculating the length of time a container is present at the PDU and determining if the PDU motor is running. The roller can be assumed to be scrubbing if the container is present for longer than a predetermined time, based on the size of a container, the speed the PDU moves a container and some allowance for slippage. Calculating the time a container is present at the PDU may comprise measuring ambient light at a light receiver, emitting lights from a light transmitter, measuring an amount of total light after the light transmitter emits light, calculating reflected light and then determining the presence of a cargo container based on the calculated reflected light. If it is determined that the roller is scrubbing power may be removed from the rive motor to prevent scrubbing, wear and overheating. |
