FLIGHT
SOL 65 END-OF-DAY DOWNLINK STATUS REPORT

Last updated: 8 Sep 1997, 16:00 PDT, Data Controller: Howard J. Eisen

Summary Report
Retransmit Requests
Sequence Planning Recommendations & Constraints
Sequence Execution Status
Telemetry Volume
Traverse Hazards (Detected)
Subsystem Reports
Telemetry Processing Anomalies
Press Release


The Little Rover amongst Stimpy,
Moe and Pumpkin



APXS Sensor Head on Moe!



SUMMARY REPORT

Sequence 56410C:



RETRANSMIT REQUESTS




SEQUENCE PLANNING RECOMMENDATIONS
Proceed with NOMINAL planning. Be aware no Persistent State Table or Level 3 HC available today.

Operational Constraints (for Sol 66 Sequence):

  1. New or changed recommendations:
    • Start Rover WEB heating earlier (12:30).
    • Do not heat and run APXS at the same time.
    • Implement new power level patch as soon as possible.
    • Investigate RCW time issue.

Engineering Requests:
  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

Operational Constraints (General):

  1. No Battery Mission
    • Do not perform APXS (and 'hold_comm') beyond 14:30 LST
    • Do not turn on APXS when heating expected as limiter reaction time may not be fast enough to prevent loadshed.
    • Limit Imaging to 09:30 to 14:30.
    • Limit Driving to 10:00 to 14:30.
    • Do not use relative waits while in hold_comm
    • Try to complete major operations by 14:30 MLST
    • 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.
    • DO NOT perform Level 3 Health Checks prior to 9:00 or after 15:00.
    • Disable battery usage for all devices.
  2. 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.
  3. Make sure sequence has as many days of runout as possible (analogous to the design of the 54910B sequence.
  4. 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
  5. 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.
    • Set Modem Heat to 15 minutes normall, 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) and Runouts.
    • Use Web_Heat_B parameter with Max temp of +30C from 12:30 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)
  6. 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.
  7. Health Checks
    • Change HC after LoadShed Reset to Level 2 instead of Level 3.
    • DO NOT perform Level 3 Health Checks prior to 9:00 or after 15:00.
    • 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.
  8. Mask all errors (except INVALID CMD) immediately prior to "Read Mem" of persistent state table. Unmask accordingly immediately afterwards.
  9. Perform Read Memory just before last downlink session
  10. Perform Sync Clock just prior to EOD shudown (or LMRE off) after Clear Errors.
  11. Disable auto shutdown
  12. DISABLE RF Wheel Temperature Sensor
  13. Insert longer wait (10 seconds) between APXS cycle start command and APXS turn-off command (turn off devices) .
  14. Future soil mechanics experiments in suspected hard material should have 6 spins of 500 counts rather than 4.


SEQUENCE EXECUTION STATUS & VEHICLE STATE

SEQUENCE EXECUTION STATUS (EOD Sol 65):

VEHICLE STATE: (AS OF COMMAND: 0, Auto Level 2 Health Check during Wait 14186
SCET: 9/8/97 19:57, MLST: Sol 65 11:36 )

BATTERY STATE/USAGE(AS OF EOD SOL 65)

SUBSYSTEM STATUS (AS OF EOD SOL 65):



TRAVERSE HAZARDS (DETECTED)



TELEMETRY VOLUME



SUBSYSTEM REPORTS

NAVIGATION PERFORMANCE:

THERMAL PERFORMANCE:

TELECOM PERFORMANCE

Telecom system performance was poorer than expected for such a small data volume, there are no telecom operational constraints for future rover operations.
The end-of-sol communication system performance for the downlink was as follows: 

SOL 65 DOWNLINK TELECOM STATISTICS	
Rov Radio Temp Low =	-4.1
Rov Radio Temp High =	40.2
Rov Radio Temp Avg =	14.8
LMRE Radio Temp Low =	15.2
LMRE Radio Temp High =	19.6
LMRE Radio Temp Avg =	17.3
Rx Current Low =	46.4
Rx Current High =	46.4
Rx Current Avg =	46.4
Tx Current Low =	
Tx Current High =	
Tx Current Avg =	0.0
LMRE Good Frames =	96
LMRE Garbled Frames =	374
Avg LMRE Link Quality%=	20.4
TX_CH_FRAMES =	33
RX_CH_FRAMES =	33
Total Frame Resends =	0
Avg Rover Link Quality%=	100.0
COM:Bad CRC Errors =	18
COM:Timeout Errors =	52786
COM:Rx Abort Errors =	742
COM:No Sync Errors =	4
COM:RX Com Errors =	38715
In planning the sequence for Sol 66 and beyond, the revised modem heating strategy used should be followed:
For rover wakeups on solar power, modem heating is only needed if communications is needed in the morning. In this situation set modem heating to 0 and reheat to 300 seconds. Also, if there are afternoon only downlink sessions, then no modem heating is required after wakeup on solar. The rover modem should be commanded in the next-day runout sequence to perform a 300 second modem reheat at wakeup. Later in the day, modem reheating should be triggered by an excessive number of frame retries on the rover-to-lander link, and the reheating should continue for five minutes or until the rover modem reaches +30 C. However, if the LMRE radio is off, then the reheat to get to +30C is not needed. This requires some coordination of timing between the LMRE ON times and the rover transmissions. The sequence planners should consider the uncertainty in event completion times introduced by any required modem reheating cycles.

MOBILITY PERFORMANCE:

POWER PERFORMANCE: 

With the exception of the battery, which was depleted on SOL 56, the remainder
of the Power Subsystem is in good health.  The power subsystem continues to
operate only on solar power.  There were no new operational problems noted in
the SOL 65 telemetry.


TELEMETRY PROCESSING ANOMALIES


PRESS RELEASE

TBD

Web Page Authors: Henry W. Stone and Allen.R.Sirota

All information on this site, including text and images describing the Rover is copyright © 1997, Jet Propulsion Laboratory, California Institute of Technology and the National Aeronautics and Space Administration.