BENTHIC LABORATORY 



399 



(Fig. 160). The card was extracted part way and released from the manipulator, leaving it 

 disengaged from the connector but still in its slot. The operation took approximately 45 min- 

 utes. A second check of the voltages on the analog -to -digital converter-card socket showed 

 that the anomalous voltage readings still existed on channels 7 and 8. Following this test, 

 Sealab was requested to disconnect the plug at the rear of the electronics rack so as to permit 

 measurements to be made on the cable itself. At this point the operations were interrupted by 

 preparation for a dive by the aquanaut assisting in the test, Art Flechsig. 



Fig. 160. Benthic labora- 

 tory location of faulty card 

 (bottom of module 3) 



Anticipating that the diode matrix card could be faulty, the manipulator was once again 

 engaged in this card, and the card was removed from the slot. The card was brought up close 

 to the TV camera and inspected visually for physical damage, particularly any damage to the 

 card pins. No evidence of physical damage was observed. The card was then moved to a 

 vacant slot in module 4 and partially inserted. Fortunately, before the card was plugged in 

 completely, an operator recalled that the particular vacant slot was not a storage slot, but was 

 a spare SCR driver card slot, completely wired, with 110 v ac appearing on the pins. The card 

 was immediately removed from this slot, and a storage slot was located at the top of module 

 11. This slot was in a very good vantage point from the TV camera, and no difficulty was ex- 

 perienced in storing the card in this position. 



During this interruption an attempt was made to use the manipulator to move camera 1 to 

 a new location. The engagement slot for the manipulator fingers is located half way down on 

 the lift bracket, in a position which is completely blind from either camera. In order to pre- 

 pare the camera for lifting it was first necessary to rotate the lift bracket from its stored 

 position at the side of the camera to the forward position. This was accomplished by wedging 

 the fingers between the bolt heads at the top of the bracket and the camera body (visible in 

 Fig. 154) and rotating both the wrist pivot and the manipulator rotate function to swing the 

 bracket out into position. The wide range of focus provided in the cameras permits the oper- 

 ator to focus on this operation, which takes place only a few inches from the camera lens. 

 Once the lift bracket was rotated into the forward position, the manipulator was retracted into 

 the field of vision of the camera and the arm realigned with the wrist pivot axis vertical, the 

 fingers rotated to the horizontal position, and the wrist pointed directly outward in the radial 

 direction. The fingers were then brought up to the top of the lift bracket to obtain a reference 

 measurement on the vertical scale provided on the manipulator. While observing the vertical 

 scale, the arm was dropped 10-3/16 in. and brought into contact with the lift bracket. The 

 manipulator was positioned so as to maintain a slight pressure on the bracket, and the hand 

 was then moved up and down until the lifting slot was located by "feel." After locating the slot, 

 the manipulator was extended to fully engage the slot, the jaws opened, and the manipulator 

 rotate jogged to center the fingers in the slot to permit full engagement. With the jaws locked 

 in the slot, the TV camera mirror was tilted through the axis of the camera to observe the 

 rear attachment to the module, and an attempt was made to lift the camera from its support 

 hook. The attempt was unsuccessful. Although it was possible to raise the camera, it was not 

 possible to clear the hook or fully support the camera by the manipulator hand. Apparently 

 either the clamp action was not strong enough or else the grip-function hydraulic leakage was 



