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Problem

--OR--

A motor or controller failure has been found, and operation must continue with less than the full number of motors.

Solution

1 Motor Controller Faults

Note: This masking is done automatically when the 3 Phase power to a failed motor is turned off. No software reconfiguration is necessary. (See next section concerning rate reduction.)

This confusion about all of this is that you will never have just one failed motor. Motors are paired by both torque-bias pairs, and by sum-tach pairs. So in some cases, a single tachometer failure will disable four motors. There should be messages for each of the disabled motors.

It is important to turn off 3 Phase power to all of the disabled motors to trigger the masking of the errors. (Also see section 2 below.)

Elevation requires at least three motor pairs to move with the CCU. If any motor controllers in elevation are faulted, the elevation axis will need to be configured to run at half-maximum rate. For reference, motors are paired in elevation as follows:

• Motors 1 & 7
• Motors 2 & 8
• Motors 3 & 5
• Motors 4 & 6

• Motors 1 & 3
• Motors 2 & 4
• Motors 5 & 7
• Motors 6 & 8
• Motors 9 & 11
• Motors 10 & 12
• Motors 13 & 15
• Motors 14 & 16

2 Masking Motor/Controller Faults

/*Message Text              F A E L L L L L L P P P T F D I  */
/*                          A Z L 1 2 3 4 5 6 F F F U E I N  */
/*                          U                 F F F R E S V  */
/*                          L                 X F P R D P E  */
/*                          T                   O O E A L R  */
/*                                              C L T R A T  */
/*                                              U     M Y E  */
/*                                              S         D  */
/* Status Byte 1 (az status 0, 000)
*/
{"AZ MOTOR CONTROL 1 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 2 FAULT ",E,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 3 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 4 FAULT ",E,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 5 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 6 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 7 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
{"AZ MOTOR CONTROL 8 FAULT ",E,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0},
                               ^
                               |
                               |

Note the arrow pointing to the second column above. This column should have 1's were motor controller status should be checked, and zero's where there are failed motor controllers. In the example above, motor controller errors are masked out on motors 2 & 4. This technique will work for motor controller faults on all azimuth and elevation motors. (On elevation motors, use the 3rd column.) Update the values if necessary, write out the file, then release control and cycle the antennaManager state off, then back to ready. Re-take control and the new values should be active.

3 Velocity Demand Reduction

The setting for the Route planner controls the demanded velocity and acceleration values:

# Max Acl and Vel for Trajectory Preprocessor
RoutePlanner.Az.MaxVel := 0.60;
RoutePlanner.Az.MaxAcl := 0.05;
# ...
RoutePlanner.El.MaxVel := 0.30;
RoutePlanner.El.MaxAcl := 0.05;

-- JoeBrandt - 19 Jan 2006