Self aligning robotic arm calibration apparatus

A calibration apparatus for use with a storage system for storing a plurality of objects in an array of object storage locations, comprising:

• an object retrieval mechanism for retrieving objects from said object storage locations;
• a calibration block configured to receive a portion of said object retrieval mechanism;
• a target imprinted on said calibration block;
• an imaging system attached to said object retrieval mechanism for capturing the image of said target for determining the relative position of a portion of the object retrieval mechanism with respect to said imaging system, wherein a line of sight of said imaging system to said calibration block is substantially parallel to the direction of retrieval motion of said object retrieval mechanism;
• a first sensor on said calibration block for determining a first position in a first direction of said object retrieval mechanism with respect to said calibration block;
• and
• a second sensor on said calibration block for determining a second position of said object retrieval in a second direction of said object retrieval mechanism with respect to said calibration block, wherein said first and second directions are substantially orthogonal to each other.