APXS on Half Dome
(2nd Location)

Sequence 55510D:

• Received telemetry for all commands not received yesterday (i.e., starting at 5101) up through the "end of nominal sequence execution".
• First 4 fo 5 APXS spectra were successfully acquired. (Joy Crisp reports that they are exceptionally clean spectra).
• Batteries depleted during acquisition of 5-th APXS spectra (i.e., during Shutdown command 5150). This caused alarm clock circuit to shutdown and the rover stayed asleep until the morning when it woke up on solar power. During the wakeup we incurred a load shed due to initial inability to support the 12 V converter. The initialization sequence waited 5 minutes, tried again, and was then able to successfully sustain the 12 V converter. The health check data confirms that the vehicle was now on solar power only.
• The Mae command which was scheduled to occur at 03:00 LST actually occurred just after solar wakeup.
• At this point the alarm clock circuit was again being powered via solar engery.
• The rover then executed Shutdown command 5169 since it still thought it was around 03:00 LST .... the LMRE was not yet on and hence the rover had not yet performed a morning time sync. Upon waking up from this shutdown, which occurred after the LMRE was turned on, the rover got a time sync and realized it was much later that it thought.
• Since it was much later than expected, Shutdown command 5170 was skipped.
• The remaining portion of the sequence up to the "nominal end of sequence exeuction" was then executed.
• Ron attributes the earlier than predicted loss of the batteries to that fact that the only data we had on the shelf life (storage/retention capability) of these batteries was for significantly lower temperatures than we actually had during cruise ... AND ... on inaccurate load estimations. The "softness" of the battery voltage during the past several nights was a partial/potential indicator that the batteries were more depleted than we had been predicting.
• All (3) Accelerometers working fine.
• Vehicle remained healthy albiet its now only a solar vehicle.
• Sequence aborted by Sequence 55610B as planned.

• Sequence queued on schedule
• All commands up to 6097 executed without error.
• APXS successfully deployed onto Half Dome at desired location (per EOD image) making contact with both the upper right and bottom contact sensor. Final deployment angle was -102 degrees.
• Due to a lander sequencing error the Rover Movie imaging sequence was not run (The sequence was loaded after it was activated).
• Vehicle remains moderately tilted towards the East. Sol 57 operations should be planned to end by 16:00 LST to insure sufficient solar power.
• All (3) Accelerometers working fine.
• Vehicle remains in excellent health.
• We expect that the first APXS spectra on the afternoon of Sol 56 will be conducted using solar power. The remaining spectra will not be taken due to lack of battery power. When the vehicle executes Shutdown command 6127 it will not wakeup on the morning when the sun wakes it up. At this point the night-time operations commands will "blow" through very quickly because the Shutdown commands will all be skipped. We expect no other significant ill effects of running this sequence despite the loss of the batteries.

• Lander shutdown at night - No retransmits possible
• Standing Request to retransmit most critical data (APID's 7, 12) 30 minutes into planned downlinks EVERY Sol due to loss of retransmit capability in Lander

Modify nominal sequence for Sol 57.

WE ARE ON A SOLAR MISSION FROM HERE ON OUT! Operational Constraints (for Sol 57 Sequence):

1. New or changed recommendations:
   
   • When shutting down for the night command the vehicle to wakeup at 07:30 LST the next morning. This is important from a telemetry standpoint in that it will limit the degree to which our telemetry plots are scrambled.
   • The ONLY time the vehicle should be "shutdown" is at the end of the day.
   • Given our current tilt, plan on shutting down for the night by 16:00 LST.
   • Disable battery usage for all devices.

1. Perform gyro/encoder turn-in-place test when feasible
2. HAVE S0050 IMAGES TAKEN DURING WAYPOINT COMMANDS ... ESPECIALLY WHEN DRIVING OVER ROUGH TERRAIN!
3. S0050 images at Low-Compression (3:1).
4. (DESIRE) Take rover images as early in the morning as possible to reduce dark noise current.
5. (DESIRE) Leave rover on until 15:45 LST to collect late afternoon thermal data, perform health check just before shutdown.
6. (DESIRE) Perform Wheelie before start of Traverse and Soil Experiment at end of Sol's traverse when practical

1. It is recommended that prior to executing a Deploy APXS command when the APXS may already be in contact the APXS should first be retracted by about 10 degrees to make up for the inherent 8-10 degrees of motion that will always occur during the beginning of the APXS Deploy command.
2. Make sure sequence has as many days of runout as possible (analogous to the design of the 54910B sequence.
3. Perform EOD Sync Clock AFTER Clear Errors so it is not skipped.
4. When shutting down for the night command the vehicle to wakeup at 07:30 LST the next morning. This is important from a telemetry standpoint in that it will limit the degree to which our telemetry plots are scrambled.
5. The ONLY time the vehicle should be "shutdown" is at the end of the day.
6. Accelerometers
   • DISABLE the Y accelerometer during moves and waypoints at risk level 1
   • CAN DISABLE the Y accelerometer during moves at risk level 2 ONLY IF planned path appears 'safe'; otherwise ENABLE Y accelerometer.
   • ALWAYS ENABLE Y accel for waypoints at risk level 2
   • Leave X accelerometer ENABLED
   • Leave Z accelerometer DISABLED
7. Heating
   • Set modem Heat and Reheat parameters both to "0" prior to shutting down for the night if LMRE is NOT going to be turned on prior to expected rover solar wakeup of ~7:15 LST. Reset them back to normal values on the morning of "runout" Sols. Disable battery usage for modem heating on runout mornings.
   • Set Modem Heat to 15 minutes normally; 10 minutes if following a night-time APXS, 0 minutes if sequence to be queued after 12:00 LST
   • Set Modem Reheat to 5 minutes and maximum modem reheat temperature 30 deg
   • Enable Modem Heat and Reheat only when LMRE is ON.
   • Perform WEB heating on days of low activity (i.e. no traverses) with no night-time APXS operations and Runouts.
   • Use Web_Heat_B parameter with Max temp of +30C from 13:00 to 15:00 when WEB heating.
   • Set Web_Heat_B parameter to -30C (-273) when not heating.
   • Always leave Web_Heat_A parameter at +40C (1197).
   • Limit image transfer after 1:00 LST (to prevent overheating)
8. Traverses
   • Do NOT move with Bogie potentiometers disabled.
     
   • Enable hazard avoidance using sensors, contacts, and laser proximity, and perform each waypoint command only once.
   • Limit each "Move Command" distance to 0.5 meter or less to enable gyro to be recalibrated and thereby reduce the amount of drift.
   • Before beginning traverses, should back up a little (~ 10 cm) to enable lasers to detect hazards which may be very close to the front of the rover. UNMASK contact sensors for this move. May want to then move forward ~ 1 cm, with contact sensors MASKED to remove any contact that may have been made during the previous backward move. Then UNMASK all contact sensors and plan subsequent waypoints.
   • When performing long waypoint traverses with "thread-the-needle" enabled like that performed on Sol 35, break the waypoints up such that the last segment is performed with "thread-the-needle" disabled. This way the vehicle will make sure (most likely) that it ends up in a location in which it can safely turn in place without climbing on nearby obstacles. If the vehicle stops because it can not find a path as wide as the turn circle, subsequent turn commands will be skipped ... and we may be able to avoid the situation we ran into on Sol 36.
9. Health Checks
   • If need to perform Level 3 health checks between Sol n, 20:00 LST and Sol n+1,8:00 LST, disable lasers (i.e., never power) to prevent them from being turned on. Re-enable afterwards.
   • Always command a Level 2 Health Check before shutdown.
   • Perform level 2 health check at the end of every traverse command
   • If possible, health checks should not be skipped as a result of traversable hazards.
10. Mask all errors (except INVALID CMD) immediately prior to "Read Mem" of persistent state table. Unmask accordingly immediately afterwards.
11. Perform Read Memory just before last downlink session
12. Perform Sync Clock just prior to EOD shudown (or LMRE off) after Clear Errors.
13. Disable auto shutdown
14. DISABLE RF Wheel Temperature Sensor
15. Insert longer wait (10 seconds) between APXS cycle start command and APXS turn-off command (turn off devices) .
16. Future soil mechanics experiments in suspected hard material should have 6 spins of 500 counts rather than 4.

SEQUENCE EXECUTION STATUS (EOD Sol 56):

Execution:	Off Nominal, LOST BATTERIES
State:	Running
Wakeup:	Solar Power, SOL 56 08:04 LTST per Rover but actually 07:54:09
Crit Errors:	Load Sheds (associatedwith battery loss)
Executing sequence 55610B

VEHICLE STATE: (AS OF COMMAND: 0 Health Check (just after Command 6094)
SCET: 8/30/97 16:22, MLST: Sol 56 14:55 )

Mission Phase:	Primary
Mode:	Executing
Config:	Moderate roll and pitch
	APXS Deployed onto Half Dome
Power:	Off Nominal (BATTERIES DEPLETED)
Device Status:	Gyro force failed
	Z accel force failed
	RFW temp. force failed
Temp (Internal):	Nominal
Temp (External):	Nominal
Temp:(Modem):	Nominal

   Parameter     Initial      Final    IMP EOD    Parameter    Initial     Final
---------------------------------------------------------------------------------
X Position (m)   -4.934      -4.934       ?      LBogie (deg)  +35.76     +17.04
Y Position (m)   -3.718      -3.860       ?      Rbogie (deg)  -22.24     -16.16
Heading   (deg)   +73.0     +89.2         ?      Diff   (deg)  +17.20     +13.44

Pitch    (deg)    +15.5      +15.5     (+ Pitch -> Front down)
Roll     (deg)    + 7.1      +15.5     (+ Roll  -> Roll to Starboard)

ADM Pos  (deg)    -92.16    -102.40     (deployed)

LFS      (deg)    -43.5       +1.9              RFS    (deg)   +42.2     -1.3
LRS      (deg)    +46.7        0.0              RRS    (deg)   -48.6     -1.3
--------------------------------------------------------------------------------

BATTERY STATE/USAGE(AS OF EOD SOL 56)

              Total         Battery   Remaining (Amp*hrs)
Category    Allocation      Initial    Final    *Predicted
--------------------------------------------------------------
Operations      10           TBD         0         0
Science         10           TBD         0         0
Technology      10           TBD         0         0
--------------------------------------------------------------
Total           30           TBD         0         0

*   at completion of sequence 55610B.

	ADM			Bumper		Solar
	UL	UR	B	RB	LB	LR	RR	RF	LF
Mask	1	1	1	1	1	1	1	1	1
State	0	1	1	0	0	0	0	0	0

	ERROR FLAGS
	Skip	GenFail	InvalidCmd	WEB_Hot	NoPwr	NonTrav	DevNA	DevFail	Timeout
Mask	1	1	1	1	1	1	1	1	1
State	0	0	0	0	0	0	0	0	0

SUBSYSTEM STATUS (AS OF EOD SOL 56):

S/S	Status	Comments
C&N	Nominal	None
MTM	Nominal	None
Thermal	Nominal	None
Power	Nominal	None
Telecom	Nominal	None

 6045 turn_by    (-4934,-3718) 34B2: LB1 RB0 DIFF2 ART2 AX0 AZ2
 6045 turn_by    (-4934,-3718) 3796: LB0 RB0 DIFF2 ART2 AX0 AZ1
 6045 turn_by    (-4934,-3718) 3A6C: LB0 RB0 DIFF2 ART2 AX0
 6045 turn_by    (-4934,-3718) 3CF3: LB0 RB0 DIFF1 ART2 AX1 AY0 AZ1
 6045 turn_by    (-4934,-3718) 3F6C: RB0 DIFF1 ART1 AX2 AY0
 6047 move       (-4934,-3712) 3F6C: RB0 DIFF1 ART1 AX0 AZ1
 6051 move       (-4934,-3712) 3F6C: RB0 DIFF1 ART1 AX0 AY0 AZ1
 6051 move       (-4934,-3729) 3F6C: RB0 DIFF1 ART1 AX0 AZ1
 6051 move       (-4934,-3751) 3F6C: RB0 DIFF1 ART1 AX0 AY1 AZ1
 6051 move       (-4934,-3774) 3F6C: RB0 DIFF1 ART1 AX0 AY0 AZ1
 6051 move       (-4934,-3789) 3F6C: DIFF1 ART1 AX0 AY0 AZ1
 6051 move       (-4934,-3812) 3F6C: DIFF1 ART1 AX0 AY1 AZ1
 6051 move       (-4934,-3835) 3F6C: DIFF1 ART2 AX0 AY1 AZ1
 6051 move       (-4934,-3860) 3F6C: DIFF1 ART2 AX0 AY1 AZ1
 6058 deploy_apxs (-4934,-3860) 3F6C: DIFF1 ART2 AX0 AY1 AZ2
 6058 deploy_apxs (-4934,-3860) 3F6C: DIFF1 ART2 AX0 AY1 AZ2

DATA VOLUME SUMMARY (BY APID)*

APID   #PKTS     #BYTES    #Mbits
----------------------------------
  4       77     22902     0.18322
  5      301     12518     0.10014
  6       14       840     0.00672
  7       16       820     0.00656
  8        0         0     0.00000
  9        0         0     0.00000
 10        0         0     0.00000
 12       16     17082     0.13666
 23        0         0     0.00000
 24        0         0     0.00000
 25      217    371552     2.97242
 29        3       739     0.00591
----------------------------------
         644    426453     3.41162

*All data downlinked on this Sol INCLUDING retransmitted data.

NAVIGATION PERFORMANCE:

ACTIVITIES:

Finish APXS overnight, move to the second site on Half Dome and deploy the APXS for the second APXS read on rock.

• Vehicle initial position:
  • Rover thinks: (-4934, -3718, 73.0)
  • Driver thinks: (-4934, -3718, 73.0)

• Cmd #6039: Run motor to 0; completed, no errors. Retract the APXS.
• Cmd #6045: Turn right 16 degs; completed, no errors.
• Cmd #6047: Move 0mm; completed, no errors. Straighten the wheels.
• Cmd #6049: Deploy APXS to -500; completed, no errors.
• Cmd #6051: Move back -150mm; completed, no errors.
• Cmd #6058: Deploy APXS -1900cnts; completed, no errors. The upper right and bottom contacts were triggered indicating that the APXS contacted with rock.

  The APXS successfully contacted with the Half Dome rock at a different location . The vehicle was still pitching down (the rear was up) at 15degs angle and the steerings were in straight position. Overall the X, Y and Z accels showed no anomalous readings today.

  Note: The rover batteries reached the end of their life time last night at around 3:00 MLST during performing an APXS command.

• The rover current position:
  • Rover thinks: (-4934, -3860, 89.2)
  • Driver thinks: (????)

  CONSTRAINTS:

  • If risk level 2 is set, then the articulation hazard is disable (i.e. driving at your all risk!!!).
  • Plan the Move command with distance 0.500m or less to avoid gyro drift.
  • Do health check level 2 after every vehicle movement.
  • Set Z accel to FORCED_BAD for all vehicle movements.
  • Set Y accel to FORCED_BAD for short vehicle movements.
  • Set Y accel to OK for RISK LEVEL = 2 vehicle movements.
  • IF navigation sensor outside limit bit is set to ENABLE in HAZ_AVOIDANCE parameter (to avoid navigation command errored out because of Y accel exceeds navigation limit), the following considerations should be taken in to account:
    • Set command TIME OUT longer to allow the vehicle finishes up the command.
    • Check for clearance behind the vehicle at starting position, the vehicle might back up half of the vehicle length (300mm).

THERMAL PERFORMANCE:

Pending

TELECOM PERFORMANCE

Pending

MOBILITY PERFORMANCE:

Pending

POWER PERFORMANCE:

Based upon the data in the health checks returned for SOL 56, it was determined that the battery had been depleted during the APXS night time operation on SOL 56. With this exception the remainder of the Power Subsystem is in good health. The power subsystem will now have only solar power available. Therefore the rover will need to be operated only during the day. There were no other operational problems noted in this SOLs telemetry. The battery had been expected to provide power for several more days of operation based upon the estimated usage. However the actual loads that the APXS and its associated power converter, regulator, and inverter place on the battery during night operations is not well quantified. This led to the poor estimation. In addition The temperature environment of the batteries during the preparation for launch and the cruise to Mars was higher than would have been desired for minimum self discharge of the battery. It has been 56 SOLs however, and that is believed to be a reaasonable time to support this mission with the primary battery.

• Bad spooler file caused problems when quering data. Had to manually build tds.out in two parts, concatenate, and then process to generate other data products.

TBD