Mark Adler

Pre-Sol Test Director Meeting:

• The test director brought together the IST from the previous Sol and expressed significant concern about our apparent aggressiveness with FIDO, as justified by FIDO team experience, that would not be realistic with respect to what our actual MER experience would be at this Sol. Up to this point in the test (as well as in previous tests), we have been operating on the assumption that we can judge operational risk on the basis of FIDO capabilities and FIDO experience. The test director believes that we should provide a somewhat more MER-like experience to the science team. In particular, we would probably not drive MER this early in the mission as far as we have driven FIDO with hazard avoidance off, no matter how good our Navcam images are. A new rule has been established to prohibit approach traverses (hazard avoidance off) for distances greater than three meters. This will impact our approach Sols, most likely adding a Sol to get within three meters before the final approach. The long-term theme group was informed.
• Another comment from the test director on his belief that our uncertainty with respect to absolute heading introduces risk to local operations is not correct. Our local operations are done with respect to images taken from our current position, and the direction of North is irrelevant to those activities. The direction of North is relevant to the images that the atmospheric group would like to take relative to the Sun and the Moon, and would be relevant to traverses with respect to orbital data, if that is ever requested. The reason for our drift of absolute heading is well understood, and is an artifact of FIDO's limited field of view on its Sun sensor. It was agreed by a previous test director that we do not need to maintain an accurate absolute heading in order to receive DTE, which is the only other operation that is potentially dependent on absolute heading. The spacecraft team has in fact recalibrated the absolute heading to support of atmosphere theme group activity requests and possible traverses with respect to orbital data.

State from Sol 17:

• The rover is in good health, and all functionality is available.
• The Sol 16 sequence completed successfully. The rover overshot by about 0.5 meters with respect to the target. The odometry was 12.26 meters. The rover is level. We did not receive any mini-TES--a diagnosis is in progress.
• This is a 34m antenna Sol. DTE this sol is 4.05 megabits, UHF is 41.7 megabits.
• Sol 18 is a Trench Sol (is that a Sol type?):
• Two mineralogy and four atmosphere mini-TES targets were requested at the start of the SOWG meeting.
• A Moon image has been requested. The atmosphere group believes that they have a good heading based on a Sun image to provide proper pointing for acquiring the Moon. The mission manager will need to check this with the spacecraft team to understand the errors in that determination.
• This Sol's main objective is to position the trenching wheel over the desired target, do a trench, and back up to look at the trench and attempt to position the rover to permit IDD operations in the trench on the next Sol.

Sequence Development:

• We sequenced a traverse to position the left front wheel for trenching. The trenching will be 200 cm which equals three revolutions. After considerable discussion, this was considered a safe number of revolutions for a complete range of surface types from loose sand to impenetrable crust. At most, we will dig in one wheel radius, which we can reliably drive back out of. The surface is almost certainly harder than that. For all surfaces, the motors will not overheat in only three revolutions. Overall, this was an adequately conservative approach for our first trenching operation during this test.
• After the trenching, the rover will roll back to a position to hopefully permit IDD operations in the trench. After considerable examination of FIDO design diagrams, arm reach calculations, and assessments of the traverse out of a trench, a drive distance was chosen to maximize the chances of the trench being accessible to the IDD instruments. However even with the best design we could muster, there is no assurance that the trench will be accessible. The uncertainty in the traverse out of the trench is of the same order of magnitude as the workspace of the arm.
• We actually had enough FIDO time to sequence imagery that exceeded the UHF allocation! We will backlog a Pancam panorama for transmission on UHF on Sol 19 (which would be received during Sol 20 planning).

We requested and received several test director rulings:

• There are no special rules for trenching to get a more MER-like experience. We are basing the trenching risk assessments entirely on FIDO experience.
• We are permitted to compress the rear Hazcam pair a bit more at 17:1 in order to make up for the 0.05 megabit oversubscription of the DTE.
• We are permitted to oversubscribe the UHF and build a backlog for later return. However we cannot control the order of return (no DPT), so we will simply get the data on UHF in the order of the observations. Furthermore, our choices on later transmission of the backlog are simply: transmit on the next Sol's UHF, or delete it. We cannot retain it for transmission on some later Sol.
• We can apply 17:1 compression to the rear Hazcam in the approach contingency, which includes front and rear Hazcams. This assures that the DTE parts of the contingency will in fact be received on the DTE.
• The uplink was approved with two minutes to go.

Sol 19 Considerations:

• See if we trenched, and if so, if we got out. See if the in situ instruments can reach the trench.
• Why wasn't there any mini-TES from Sol 17?
• Request the backlogged Pancam panorama from Sol 18 on the Sol 19 UHF (which would be received during the Sol 20 planning). If it is not requested, it will be deleted.
• Determine how well the recalibration of the front Hazcam range maps has been done. Determine what the proper approach would be for a successful IDD operation based on our current trust or lack of trust in the front Hazcam range maps.
• Get a ruling from the test director on whether the available data is adequate to perform IDD operations, with respect to Hazcam or Navcam of the area under the current rover location. (On MER we would require a Hazcam a meter or so back from the rover location of the IDD operation, we well as a Hazcam from the rover location.)

Cumulative Comments:

• It is important for the theme groups to sequence their requested observations, and in particular they should sequence their highest priority observations first. On Sol 15, the highest priority Pancam was not sequenced by the theme group, but the second and third were.
• Given extra time during sequence development, it is worthwhile to review the science priorities as well as to review, in sequence order, the visualizations of the image and remote spectroscopy requests.
• The modeling for IPS points needs to be updated. Ground testing should be performed to determine the duration of IPS measurements as a function of coadds. In addition, the modeling for Navcam images needs to be updated, since they appear to take up twice as much space in the resource modeling as they should at 16:1 image compression after a 12:8 pixel compression.
• The tools do not provide a means to determine the actual length of planned traverse segments. Furthermore, there are no good estimates with uncertainty of the meters per minute that the rover (with hazard avoidance on) can traverse as a function of the terrain type. Finally, there is limited information on the dead reckoning capability of the rover on gyros with respect to heading errors. Overall, there was no way to estimate the traverse duration or error based on the traverse design and terrain expectations, other than the experience of spacecraft team eyeballing the situation. This would not be acceptable in a real mission.
• We need to request a change control board to adjust the Hazcam data volume in the command dictionary from 2.1 to 1.05 Mbits.
• Clarification from PI: we have a mission success location if a) use two out of three in situ instruments, and b) the PI is willing to advocate that the science is new and different enough to make it a location.
• We need a ruling from the test director on whether we need Hazcam from one meter back and Hazcam at the current location in order to perform an arm operation. This may be affected by FIDO's ability to implement a stop one meter short after a long traverse. If not, we may not ever be able to do targets of opportunity after a long traverse.
• Before this Sol, we are at 2 out of 3 locations, zero trenches, and approximately 142 meters. After this Sol, we should have a trench (and another few meters). On Sol 19, we should be able to IDD the trench, which would provide the third mission success location. If that all works out, then all we need to do for mission success is drive another 60 meters. That could easily be done in two Sols, and more than that has been done in one Sol. There are eight Sols left.
• This was this mission manager's last Sol in this test. It has been a pleasure to work with the team. Good luck for the remainder of the test.

Special Notes:

• Starting on Sol 16 and on all subsequent sols, the afternoon sol will begin at 12:15 PM with all subsequent events shifting later by 15 minutes.

Updated sequence development schedule starting at 0900 and 1415:

• 70 minute Sequence Design
• 10 minute Sequence Validation
• 10 minute Sequence Approval

We have a test director flight rule to not use approach moves (hazard avoidance off) for total moves of more than three meters.

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