Retransmit Status:

Received no new retransmitted packets.

• Received commands 26135 - 26167
• Woke up via Solar at 7:32 LST, Sol 27
• Aborted by 52710D at command 26167 just at the intended "end of nominal sequence execution".

• Attempt to dislodge 'rock' stuck in wheel successful as initial soil mechanics and moves executed without motor stall
• All subsequent moves and turns executed successfully (no errors)
• Waypoint #1 and #2 executed successfully (no errors)
• EOD image indicates that vehicle is currently on the edge of the mermaid sand dune
• Overall vehicle is VERY healthy.

Images:
• Command 23073
  • APID 8
  • Missing packets 23 through 35
  • SCET ~1997-07-27T16:16:06
• Command 23074
  • APID 8
  • Missing packets 27 through 53
  • SCET ~1997-07-27T16:27:08
APXS:
• Command 22645
  • APID 12
  • Missing all packets (2)
  • SCET ~1997-07-26T19:25:25.325

1. REMOVE explicit heating of modem prior to morning image transfer (superseded by maximum reheat temperature setting in "general constraints")
2. Continue to DISABLE hazard avoidance for stall conditions/hazards during Sol 27.
3. Leave X accelerometer ENABLED
4. Leave the Z accel DISABLED
5. DISABLE the Y accelerometer during waypoints and moves at risk level 1. ENABLE Y accel for waypoints and moves at risk level 2
6. Enable hazard avoidance using sensors, contacts, and laser proximity, and perform each waypoint command only once
7. If possible, health checks should not be skipped as a result of traversable hazards
8. 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.

1. Wakeup every 2 hours during the night Sol 27. Data from auto health checks will be used to generate overnight thermal profiles.
2. Waypoint Navigation:
   • Continue to perform waypoint commands.
   • Take seperate S0055 images after each individual waypoint command.
   • Take S0050 (Rover Movie) of each individual waypoint command.
3. Take pre and post 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.

1. Mask all errors (except INVALID CMD) immediately prior to "Read Mem" of persistent state table. Unmask accordingly immediately afterwards.
2. Set Modem Reheat to 5 minutes and maximum modem reheat temperature 30 deg.
3. 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.
4. Terminate heating at 15:00
5. Disable auto shutdown
6. Set Modem Heat to 15 minutes; 10 minutes if following a night-time APXS)
7. Set alarm based wakeup to 08:00 LST
8. Perform Read Memory just before last downlink session
9. DISABLE RF Wheel Temperature Sensor
10. DISABLE Z accelerometer.
11. Perform Time Sync just prior to EOD shudown.
12. Always command a Level 2 Health Check before shutdown.
13. Perform level 2 health check at the end of every traverse command
14. Limit image transfer after 1:00 LST (to prevent overheating)
15. Limit each "Move Command" distance to 1 meter or less to enable gyro to be recalibrated and thereby reduce the amount of drift.
16. Insert longer wait (10 seconds) between APXS cycle start command and APXS turn-off command (turn off devices)
17. Perform WEB heating on days of low activity (i.e. no traverses) with no night-time APXS operations, and Runouts from 13:00 (noon) to 15:00 MLST.
18. Use Web_Heat_B parameter with Max temp of 30C.
19. Future soil mechanics experiments in suspected hard material should have 6 spins of 500 counts rather than 4.

SEQUENCE EXECUTION STATUS:

Execution:	Nominal
State:	Idle
Wakeup:	Solar, 1997 212 SOL 25 07:32 LTST
Crit Errors:	None
Executing sequence 52710D

VEHICLE STATE: (AS OF COMMAND: 27113, Commanded Health Check SCET: 7/31/97 21:24:56 )

Mission Phase:	Primary
Mode:	Executing
Config:	Nominal
	At edge of mermaid dune
Power:	Nominal
Device Status:	Z Accelerometer Forced bad
	RFW Temp. sensor Forced Bad
	LF Wheel Motor unjammed
Temp (Internal):	Nominal
Temp (External):	Nominal
Temp:(Modem):	Nominal

---

   Parameter    Initial      Final     Imp EOD    Parameter       Initial  Final
---------------------------------------------------------------------------------
X Position (     -2.349     -5.256         ?       LBogey (deg)   -2.72    -3.60
Y Position (m)   +3.938     +2.907         ?       RBogey (deg)   -8.48    -0.80
Heading  (deg)   +214.7     +16.6          ?       Diff   (deg)   -3.68    -3.36

Pitch    (deg)    +1.2     +1.2  (+ Pitch -> Front down)
Roll     (deg)    -5.9     +2.4  (+ Roll  -> Roll to Starboard)

ADM Pos  (deg)    -1.28    -1.28  (Fully Retracted)

LFS      (deg)     -9.6      0.0     RFS    (deg)   -16.6   -1.3
LRS      (deg)    +11.5      0.0     RRS    (deg)   +15.4   -1.9
--------------------------------------------------------------------------------

BATTERY STATE/USAGE**

              Total         Battery   Remaining (Amp*hrs)
Category    Allocation      Initial    Final    *Predicted
--------------------------------------------------------------
Operations      10           4.437***  4.388     4.288
Science         10           5.620     5.620     5.620
Technology      10           7.534     7.534     7.534
--------------------------------------------------------------
Total           30          17.591    17.542    17.442

*** This is believed to be lower than real by about 0.4 Ahrs
     due to some change in the battery state of charge registers.
**  reflects transfer of two hours from technology to science
*   at completion of sequence 52610B.

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

S/S	Status	Comments
C&N	Nominal	None
MTM	Nominal	RF Wheel Temp Sensor H/W failure
Thermal	Nominal	None
Power	Nominal	None
Telecom	Nominal	None

27050 turn_to    (-2199, 4419) 930C: AZ1
27057 move       (-2632, 4121) 97B3: AX2 AZ1
27057 move       (-2704, 4072) 983C: AZ1
27062 goto       (-3116, 3779) A49C: AZ1
27062 goto       (-3283, 3526) A8B3: AZ1
27062 goto       (-3324, 3464) A960: AZ1
27062 goto       (-3409, 3332) A9A1: AZ1
27062 goto       (-3563, 3095) A8AC: AZ1
27062 goto       (-3588, 3057) A979: AZ1
27062 goto       (-3718, 2844) A981: AZ1
27062 goto       (-3863, 2616) A82B: AZ1
27062 goto       (-3980, 2439) A91E: AZ1
27064 turn_at    (-4063, 2289) 713C: AZ1
27068 goto       (-4052, 2281) 6BF7: AZ1
27068 goto       (-5127, 2822) 6AA2: AY0
27068 goto       (-5143, 2831) 6A4C: AZ1
27068 goto       (-5190, 2862) 6827: AZ1
27068 goto       (-5243, 2897) 678C: AY1 AZ2
27070 turn_to    (-5256, 2907) 1D25: AZ2

DATA VOLUME SUMMARY (BY APID)*

APID   #PKTS     #BYTES    #Mbits
----------------------------------
  4       30      8817     0.07054
  5       88     10906     0.08725
  6        2       120     0.00096
  7        1        40     0.00032
  8      102    188348     1.50678
  9        0         0     0.00000
 10        0         0     0.00000
 12        0         0     0.00000
 23        0         0     0.00000
 24        0         0     0.00000
 25      423    828292     6.62634
 29       15     18010     0.14408
----------------------------------
         661   1054533     8.43626

*All data downlinked on this Sol INCLUDING retransmitted data.

NAVIGATION PERFORMANCE:

ACTIVITIES:

The rover is heading to Mermaid Dune, tries to finish up what have left off in yesterday traversal.

• Vehicle initial position:
  • Rover thinks: (-2349, 3938, 214.7)
  • Driver thinks: (-2334, 4386, 197.0)

• Cmd #27041: Soil mechanics (motor=0, counts=-1200, cycle=1); completed, no errors.
• Cmd #27043: Move -140mm, completed, no errors. readings.
• Cmd #27050: Turn to heading 215degs; completed, no errors.
• Cmd #27052: Move 350mm; completed, no errors.
• Cmd #27054: Soil mechanics (motor=5, counts=500, cycle=6); completed, no errors.
• Cmd #27057: Move 500mm; completed, no errors. The X accel showed an anomalous reading (Xmin=-0.234g, Xmax=0.094g).
• Cmd #27059: Soil mechanics (motor=5, counts=500, cycle=6); completed, no errors.
• Cmd #27062: Goto waypoint (-4089, 2222); completed, no errors.The vehicle traversed through a benigned terrain, only one laser spot dropped off during the entire traversal.
• Cmd #27064: Turn toward target (-5298, 2973); completed, no errors.
• Cmd #27066: Move -70mm; completed, no errors.
• Cmd #27068: Goto waypoint (-5298, 2973); completed, no errors. No laser spot dropped out during this traversal. The Y accel showed anomalous reading (Ymin=-0.141g, Ymax=0.016g).
• Cmd #27070: Turn to heading 17 degs; completed, no errors.
• Cmd #27071: Move 0mm, straighten the steerings; completed, no errors.
• The rover completed all the traversals and reached its destination at the Mermaid Dune. The total traversal distance for the day is 4.658m, and the total traversal distance to date is 50.900m. The X and Y accels showed anomalous readings at least once during these traversals. The Z accel continuously showed anomalous readings in every traversal command.
• Y and Z accel analysis:
• During sol25 the Y and Z accel test was performed by reading Y and Z accel alternately using call_function_cmd() to call an_read() to read each Y and Z accel channel without filtering for 25 times.
• The rover current position:
  • Rover thinks: (-5256, 2907, 16.6)
  • Driver thinks: (???)

  CONSTRAINTS:

  • 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 risk level=1 movements.
  • Set Y accel to OK for risk level=2 movements.

THERMAL PERFORMANCE:

• The CPU and PWR boards are approaching a high of 35 C and will not exceed FA's.
• Sol 26 pm Max recorded: 39.9 PWR, 39.3 CPU, 2.0 MAE
• Sol 27 am Min recorded: -25.7 WEB, -20.2 CPU, -50.6 MAE
• The RF temperature sensor is still bad and remains forced failed.

  Recommendations:

  Perform wakeup every 2 hours for overnight thermal data on Sol 27 evening/Sol 28 morning. Tests 9.1 and 9.9 will be requested for Sol 28 morning

TELECOM PERFORMANCE

Telecom system performance was particularly good this sol, and the revised rover mdem heating strategy recommended for this sol was effective. A review of the data plots for this sol aain shows correlation between good rover-to-lander communication throughput and rover modem temperaturesabove roughly +30 C. There are indications that three, and perhaps four, modem reheating cycleswere initiated automatically by the rover after experiencing excessive retries on the rover-to-lader link.

STATISTICS

• The rover's circumnavigation of the lander, now in it's third day, brought the rover out along a main lobe of the LMRE antenna, where the gain is within about 5 dB of maximum. Two sets of rover images, 1 near Mini- Matterhorn, and 1 near Squash, were successfully transmitted over the link.

Rov Radio Temp Low =    -18.6
Rov Radio Temp High =   33.3
Rov Radio Temp Avg =    15.1
LMRE Radio Temp Low =   2.0
LMRE Radio Temp High =  21.8
LMRE Radio Temp Avg =   15.7
Rx Current Low =        43.5
Rx Current High =       49.3
Rx Current Avg =        46.0
Tx Current Low =        142.1
Tx Current High =       162.4
Tx Current Avg =        151.8
LMRE Good Frames =      3088
LMRE Garbled Frames =   2413
Avg LMRE Link Quality%= 56.1
TX_CH_FRAMES =  6396
RX_CH_FRAMES =  6385
Total Frame Resends =   11
Avg Rover Link Quality%=        99.8
COM:Bad CRC Errors =    8
COM:Timeout Errors =    16556
COM:Rx Abort Errors =   615
COM:No Sync Errors =    0
COM:RX Com Errors =     27194

RECOMMENDATIONS

In planning the sequence for Sol 28 and beyond, the revised modem heating strategyfirst used today (Sol
27) should be followed:

The rover modem should be commanded in the next-day runout sequence to perform a 600 second modem
heating at wakeup.  If no overnight APXS operations are to be conducted, the wakeup rover modem
heating should be extended to 900 seconds.  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.  The sequence planners should consider the uncertainty in event completion
times introduced by any required modem reheating cycles.

We are continuing our suspension of the previous recommendation to operate on LMRE-A for ten minutes
prior to the expected rover wakeup time.

MOBILITY PERFORMANCE:

• The activities today included 2 Waypoints as well as several moves and turns. The two waypoints and all moves/turns executed nominally.
• The wheel reversal and subsequent backup left the LFWheel clear of any obstruction. This was verified by an image (27047).The currents reported were in the 20-30mA range.
• The mobility system is healthy.
• Daily Odometry: 4.658 m
• Total Odometry: 050.900 m
• Average Wheel Odom: 71.895 m

  Recommendations:

  • Consider enabling avoidance of stall hazards.

POWER PERFORMANCE:

Based upon the data returned in the health checks returned in SOL 27, the Power Subsystem is in good health with no operational problems noted. The output of the short circuit current cell in the MAE is used with the MAE temperature measurment to predict the solar panel power available to the rover at that time. By comparing this derived channel for the same time for sequential days one should be able to determine any changes in the capability of the solar panel. There are some factors that make it impossible to do a quantitative assessment of the solar panel such as the change of tilt from day to day and the fact that we don't have data for the same time each day. However the general trend of the available power can be seen and for the rover on Mars, it is decreasing. This is in spite of the fact that Mars continues to decrease its distance from the sun. The decrease in solar panel power availableis, however in agreement with the data taken by the MAE dust experiment.

• None

TBD