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Daily Update - 7/25/05
Rocks and Cobbles on the Way to 'Erebus'
Opportunity Status for sol 524-530
The Opportunity team's current strategy for driving alternates segments of using visual odometry to check for slippage with segments of blind driving for less than 5 meters (16 feet). The strategy and hard work designing and commanding drives through troughs between ripples contributed to the rover making 89 meters (292 feet) of progress over three drive plans.
Rocks and cobbles have begun appearing in images of Opportunity's new surroundings, for the first time in many weeks of traversing through rippled terrain.
The rover's power team reported a dust-cleaning event on Opportunity between sols 524 and 526. Daily power output from solar panels increased from about 500 watt hours to about 650 watt hours.
Sol-by-sol summaries:
Sol 524 (July 15, 2005): The uplink team planned and executed a successful 27-meter (89-foot) drive. This signified the first use of a combination of short segments of blind driving followed by small slip-check drive segments. One small rock was seen in imaging.
Sol 525: Opportunity performed remote sensing and repeated a right-front steering actuator diagnostic test from sol 435. The actuator moved slightly more than in the last test, but there was no significant change.
Sol 526: Rover planners used the drive technique established on sol 524 to complete a successful 32-meter (105-foot) drive. Small cobbles were seen in imaging.
Sol 527: Opportunity used the sol for remote sensing and battery recharging.
Sol 528: The uplink team planned a drive of 30 meters (98 feet), continuing in the troughs and crossing one ripple crest. The crest was estimated at 8.5 percent slope. However, the drive did not succeed because of a timeout on the first turn command. The duration was set to 15 seconds for a 15-degree turn. The rover made 14.9 degrees of progress before using up the allotted time.
Sol 529: On this second sol of a two-sol plan, the rover performed remote sensing.
Sol 530 (July 21, 2005): The uplink team repeated the planned drive from sol 528, with changes to the timeout durations of turn and waypoint commands. The drive succeeded in covering 30 meters (98 feet). It brought Opportunity's total odometry to 5,555 meters (3.45 miles).
Daily Update - 7/25/05
Spirit in Target-Rich Environment
Spirit Status for sol 546-551
Spirit had an excellent week, driving every planning cycle. The rover drove more than 70 meters (230 feet) closer to the summit of Husband Hill.
The science team has identified an outcrop suitable for inspecting with instruments on the robotic arm. On Sol 550 (July 20, 2005), Spirit approached that target. The following sol the rover "bumped" forward to get into good position for extending the arm to the target.
Sol-by-sol summaries:
Sols 546 and 547 (July 16 and 17, 2005):
Spirit drove about 12.5 meters (41 feet) on sol 547.
Sol 548:
Spirit drove about 20 meters (66 feet).
Sols 549:
Spirit drove about 30 meters (98 feet).
Sols 550:
Spirit drove about 10 meters (33 feet).
Sols 551 (July 21, 2005):
Spirit drove about 1 meter (three feet) to get into position for using the robotic arm's tools on an outcrop target. As of sol 551, Spirit has an odometer total of 4,685 meters (2.91 miles).
Daily Update - 7/15/05
Spirit Investigating 'Independence'
Spirit Status for sol 538-545
Spirit is healthy. On sol 538 (July 8, 2005), Spirit attempted its rock abrasion tool to brush the rock called "Independence." The tool's contact switches did not engage the rock face, and the brushing did not occur. A safety check precluded further use of the robotic arm. The prescribed operation should have been:
- brush with rock abrasion tool;
- place the alpha particle X-ray spectrometer;
- observe with the microscopic imager;
- place the Moessbauer spectrometer.
From this particular down position for the rock abrasion tool (and the fact that use of the arm was precluded), the rover would not have been able to switch to the Moessbauer spectrometer. The entire weekend's worth data collection by the Moessbauer spectrometer would have been lost. However, the arm preclusion was discovered Friday evening and the team had enough time to modify the robotic arm sequence and recover the weekend's Moessbauer integration time. The sequence of events became:
- enable robotic arm activity
- move the joint angles to avoid an arm position that would prompt collision-avoidance software to halt to arm movements;
- observe with the microscopic imager;
- place the Moessbauer spectrometer.
The recovery plan ran well. The Moessbauer spectrometer was placed and it collected data all weekend.
On later sols the tool turret on the arm was rotated to the alpha particle X-ray spectrometer. That instrument examined the same target for about 17 hours, recovering the alpha particle X-ray spectrometer integration time lost on July 8 (sol 538). Spirit also found time during the weekend to fill in the remaining panoramic camera images for an "Independence" color panorama.
Sol-by-sol summaries:
Sols 538 and 539 (July 8 and 9):
The rover team recovered a long reading with Spirit's Moessbauer spectrometer after a planned brushing with the rock abrasion tool did not occur. The rover also took images of the target rock, "Independence" with the microscopic imager and continued taking component images for a large color panorama of the "Independence" scene.
Sols 540 and 541 (July 10 and 11):
Spirit continued collecting data with the Moessbauer spectrometer and taking images for the "Independence" panorama.
Sols 542 and 543 (July 12 and 13):
Spirit continued the Moessbauer spectrometer integration, then changed the tool to the alpha particle X-ray spectrometer late in the afternoon and collected data with that instrument overnight. In the morning of sol 543, Spirit changed back to the Moessbauer spectrometer for its final few hours of integration. Spirit stowed the robotic arm and bumped back about 80 centimeters (2.6 feet) to a good position for observing "Independence" with the miniature thermal emission spectrometer, now back in use.
Sols 544 and 545 (July 14 and 15):
The plans for these sols are for a 25-meter (82-foot) drive followed by a sol of remote-sensing observations from the new location.
Daily Update - 7/15/05
Edging Toward 'Erebus'
Opportunity Status for sol 518-524
Opportunity made impressive progress toward "Erebus Crater" during the week. Four sols of driving totaled 57 meters (187 feet), while slipping less than 10 percent on each drive. A longer drive was plotted for the fifth day.
The rover has continued to drive down ripple troughs. We have a series of checks in place to prevent excessive bogging down, including, tilt, roll, pitch limit checks, current checks and slip checks (set at 40 percent slip).
We look forward to more progress south over the coming week.
Sol-by-sol summaries:
Sol 518 and 519 (July 9 and July 10, 2005):
In light of extensive driving and data collection the previous week, these sols were designed to conduct light remote sensing, recharge batteries, and downlink data to free up memory space on the rover.
Sol 520:
The uplink team designed a 16-meter (52-foot) drive. Opportunity completed 10.34 meters (33.92 feet) of the drive before tripping a mobility-goal error. There was a bad position estimate given to the onboard slip-checking software, so it incorrectly thought the rover was 0.5 to 1 meters (1.6 to 3.3 feet) back from its actual position, thus making insufficient progress because it thought it was slipping excessively. However, analysis by the mobility team on the ground determined the true slip, and we were "go" to drive the following sol.
Sol 521:
Opportunity completed a successful drive of 15.2 meters (about 50 feet) without any faults.
Sol 522:
The rover completed another successful drive of 15 meters (49 feet), with only 6.4 percent reported slip.
Sol 523:
We drove 16.2 meters (53 feet) of a planned 20-meter (66-foot) drive. The drive stopped short because onboard slip-checking software was having difficulty tracking the rover's rear wheel tracks, which are used as a reference point to monitor the slip. Opportunity does not want to keep trying to drive if it is unsure of how much it is slipping, so the team sets a limit to this failure count. This prevents bogging down in the terrain.
Sol 524 (July 15):
The uplink team planned a drive of 27 meters (89 feet). The drive plan is the first in Opportunity's current terrain using a combination of short segments of blind driving followed by shorter segments (40 centimeters, or 16 inches) of slip-check driving. This drive strategy is designed to allow us to drive farther by using a less time-consuming drive option while still verifying every 5 meters that we are not bogging down.
Odometry total after sol 523 drive: 5464.09 meters (3.39 miles).
Daily Update - 7/12/05
Done with this Dune
Opportunity Status for sol 503-509
Opportunity spent the week positioning itself for robotic-arm work and studying the area at the base of "Purgatory Ripple." The rover has examined its tracks (which contain material carried out of Purgatory Dune by the wheels) and undisturbed dune material.
Sol-by-sol summaries:
Sols 503 and 504 (June 23 and 24, 2005): Opportunity drove partway to the position for robotic-arm work on Purgatory Dune. Remote sensing over these two sols included a panoramic camera image of the robotic-arm work volume, a navigation camera panorama, and a miniature thermal emission spectrometer raster.
Sol 505 and 506: Opportunity acquired two microscopic imager mosaics and an alpha particle X-ray spectrometer integration on soil before a short drive to the position for examining the tracks.
Sol 507: This was the first of three days using the robotic arm at Purgatory Dune. The rover completed two microscopic imager mosaics and an alpha particle X-ray spectrometer integration. Opportunity also fired up the miniature thermal emission spectrometer for an afternoon raster.
Sol 508: The rover completed a 24-hour Moessbauer integration and collected more data with the miniature thermal emission spectrometer.
Sol 509 (June 29, 2005): Opportunity collected data with the alpha particle X-ray spectrometer and made a late-night observation of the dune with the miniature thermal emission spectrometer.
Daily Update - 7/12/05
Pushing Away from Purgatory
Opportunity Status for sol 510-517
This week Opportunity finished examining "Purgatory Dune" and started driving again. The first few drives were to the north so that possible paths to the south could be imaged and evaluated. The next few steps took the rover east, then southward down a wide trough. A new set of "rules of the road" have been developed and implemented to prevent the rover from getting bogged down again.
The miniature thermal emission spectrometer has also been cleared for regular use, and has returned some useful science products during the last week.
Sol-by-sol summaries:
Sol 510 (June 30, 2005): Opportunity finished characterizing Purgatory ripple with microscopic imager pictures of soil (tracks and undisturbed), and took a first step back. The rover collected several images to document the 2.1-meter (6.9-foot) drive. Visual odometry confirmed that slip was less than 10 percent during the short traverse. After the drive, the rover took pictures of the surroundings to evaluate possible safe pathways to the south.
Sol 511: Opportunity backed up 8.5 meters (28 feet), and again imaged the terrain to the south. The drive used visual odometry and slip checks to stop the rover if it failed to make progress.
Sol 512: The long-term goal for Opportunity is to drive south and slightly east. Before continuing on this path the rover must either go east or west to sidestep Purgatory Dune. Extensive remote sensing with the panoramic camera and navigation camera was done this sol to assist in the decision.
Sol 513: With all imaging needed for driving already acquired, Opportunity spent the sol doing atmospheric observations, dust monitoring, and also imaging of the magnets with the panoramic camera.
Sol 514: The engineering and science team took an Independence Day break today, and the rover executed its planned runout science sequence, which included atmospheric observations with the panoramic camera.
Sol 515: Imaging acquired over the weekend showed that the path to the east contained very small ripples (less than 6 centimeters or 2.4 inches), and led to a wide trough to the south. This sol, rover planners sequenced a 5.5-meter (18-foot) backwards drive over old tracks, then turned in short segments (less than 20 degrees), and drove east 2.5 meters (8.2 feet) over one small ripple. Tilt limits, visual odometry failure limits, and cycle limits were employed to prevent the rover from bogging down. The drive succeeded as planned.
Sol 516: An 11-meter (36-foot) drive to the east crossed two small ripples and positioned the rover to enter the trough leading south. Limits and slip checks were used to ensure that Opportunity would not get stuck.
Sol 517 (July 8, 2005): A new safety check was added to this drive: The drive current limits were lowered from 1 ampere to 0.4 amperes. The standard safety checks were also used on this drive, designed to take Opportunity 4 meters (13 feet) east to the north end of the trough, then 11 meters (36 feet) south through the trough.
Opportunity's total odometry after sol 517 is 5,406.6 meters (3.36 miles).
Looking ahead:
Opportunity will continue the drive south, more slowly than before to ensure a safe path.
Daily Update - 7/12/05
Spirit Scuffs
Spirit Status for sol 532-537
Over the Fourth of July weekend, Spirit completed a robotic-arm campaign which had some surprising results. It turned out that targets at "Independence Rock" seem to have less iron than expected. This result prompted the science team to take a closer look. On sol 536 (July 6), because the grinding teeth on the rock abrasion tool are worn, the rover team decided to remove some of the surface area by scuffing it with the front left wheel.
The scuff worked as follows:
- Spirit moved into position with a turn in place.
- Rotated only the front left wheel -- reverse 1 radian.
- Rotated only the front left wheel -- forward 2 radians.
- Rover used onboard visual odometry.
- Repeated steps 2 through 4, two more times.
- Turned in place back to the starting position in order to present the "scuff" to the robotic-arm workspace.
Since the rover gets better alpha particle X-ray spectrometer and Moessbauer spectrometer spectral readings when we let them run long (more than 10 hours for the alpha particle X-ray spectrometer and more than 20 hours for the Moessbauer spectrometer). The rest of the weekend (sols 538 to 541) will be dedicated to work using the instruments on the robotic arm.
Sol-by-sol summaries:
Sol 532 to 535 (July 2 to July 5, 2005):
Over this period, Spirit took data with the alpha particle X-ray spectrometer and the Moessbauer spectrometer and made observations with the microscopic imager and remote-sensing instruments. The results motivated a decision to do more work with the robotic arm.
Sol 536:
The scuff today worked nicely, except that it did not seem to remove a whole lot of material from the place Spirit scuffed. Overall, the rover only scuffed 9 radians on the rock surface, which is less than 1.5 wheel revolutions. Engineers received no errors during the drive, and it looked like all drive-related telemetry was within acceptable parameters.
After the scuff and before Spirit moved back to its original position, the rover took a picture with the hazard avoidance camera in order to see the effect the scuff had on the wheel treads.
The rover team favored the forward wheel rotation because this creates a torque that needs to work against gravity in order to rotate the rover body.
Sol 537 (July 7, 2005):
Spirit started an "Independence" 360-degree color panorama. This mosaic will be run all weekend.
Daily Update - 7/5/05
Back to 'Purgatory'
Opportunity Status for sol 497-502
Opportunity made its way back toward "Purgatory Dune" for a chance to explore its own tracks. During the drive the rover stopped along the way to study the soil at "North Dune."
Sol-by-sol summaries:
Sol 497 (June 16)
This was the second sol of a two-sol plan. Today was dedicated to remote sensing, including panoramic camera usage with 13 filters and stares with the miniature thermal emission spectrometer.
Sol 498
On sol 498, Opportunity deployed its robotic arm to get a "taste" of the North Dune. The rover did this using both the microscopic imager and the alpha particle X-ray spectrometer. The next sol, the rover moved slightly back (about 40 centimeters or 1.3 feet) and then slightly forward (the same distance) in a move designed to place it on an optimal approach, ready to drive to its destination on Purgatory Dune. The last sol of this three-sol plan was again spent as a remote-sensing sol.
Sols 501 and 502
Opportunity had been trying to line itself up with the science target by performing arcs. Due to nature of this terrain, it had not been yawing as much as expected so its approach was slightly off. The team decided to have the rover try a turn in place. Engineers had been staying away from turning in place because Opportunity has a bad steering actuator on one wheel, and this makes turning in place more cumbersome. This turn in place, however, had some advantages because it was in the right direction and it was a small turn. The rover performed it perfectly.
The turn in place churned up soil in front of Opportunity. This made the immediate area in front of the rover more prone to slippage. Opportunity detected excessive slippage (more than 30 percent) when it attempted to perform the first of two 25-centimeter (9.8-inch) arcs. The visual odometery system detected that the first arc went only 17.1 centimeters (6.7 inches). This constituted a 32 percent slip. The engineers had limited the acceptable amount of slippage to 30 percent, so the rover was not commanded to perform the second arc. The next sol was a remote-sensing day.
Sols 503 and 504 (June 22 and 23)
The team planned another drive consisting of three 25-centimeter (9.8-inch) arcs. This drive was calculated to bring the rover to its destination at Purgatory Dune.
Daily Update - 7/1/05
Spirit Observes 'Independence'
Spirit Status for sol 524-531
Spirit has had an extremely successful week. On June 24, 2005 (sol 524), the rover drove 26 meters (85 feet). The following two sols, Spirit performed remote sensing. On June 27 (sol 527), Spirit completed another tricky drive and progressed 22.5 meters (74 feet). At this new site, scientists found an intriguing rock target they informally named "Independence Rock." Spirit will observe this layered rock with instruments on the robotic arm over the long Fourth of July weekend. The rover team commanded a small move positioning Spirit in front of this target, and the rover has begun the science observations. The first attempt to brush Independence Rock with the rock abrasion tool was unsuccessful because contact switches didn't connect. However, the rover team picked a new target in the same general area for Spirit to brush with the rock abrasion tool and analyze with the alpha particle X-ray spectrometer and Moessbauer spectrometer over the weekend.
Sol-by-sol summaries:
Sol 524 (June 24, 2005): Spirit completed an extremely successful drive, advancing 26 meters (85 feet).
Sol 525: On this remote sensing sol, Spirit made observations with the panoramic camera and miniature thermal emission spectrometer.
Sol 526: Spirit checked for dust devils with the navigation camera, took readings with the miniature thermal emission spectrometer and observed the sunset with the panoramic camera.
Sol 527: Spirit drove 22.5 meters (74 feet), evidence of successful work by rover planners.
Sol 528: Spirit executed a small drive of 2.8 meters (9 feet) to position itself to have an interesting rock target, dubbed "Franklin," within the work volume of the robotic arm.
Sol 529: The team planned a sol of using the microscopic imager, rock abrasion tool brush, and alpha particle X-ray spectrometer in preparation for the long weekend plan. However, the rock abrasion tool's contact switches didn't trip, and software responded properly by precluded the robotic arm from doing the subsequent work with the alpha particle X-ray spectrometer.
Sol 530: This plan was difficult and long because it was part of a three-sol plan in preparation for the weekend. Engineers had to re-enable the robotic arm quickly. Spirit performed a 22.5-hour Moessbauer spectrometer integration on Franklin.
Sol 531 (July 1, 2005): This will be the second sol of a three-sol plan, with another long Moessbauer spectrometer integration (23 hours) on Franklin.
Total odometry as of the end of sol 528 (June 28, 2005) is 4,583.38 meters (2.85 miles).
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