AUVSI and ISU Presentations

Presentations were recently made to two local groups that featured the exploration rovers that were recently acquired by the Northern California chapter of the Mars Society.

Dr. Chris McKay, Geoff Chu and Andrew Klofas discussed the rovers and their purpose with an enthusiastic crowd at the August 4th meeting of the Association for Unmanned Vehicle Systems International Silicon Valley chapter (AUVSI-SV), held at the Flight Operations Center at Moffett Field. Attendees enjoyed the opportunity to control one of the rovers on the lawn in front of the Flight Operations Building.

One of the attendees of the meeting requested a rover demonstration for an educational outreach project he is affiliated with, and another expressed interest in helping prepare the rovers for their intended uses. One rover will be stationed at the Mars Desert Research Station (MDRS), a Mars analog research facility in Utah sponsored by the Mars Society. The other rover is earmarked for the Mars Society's education outreach program in the Bay area.

On August 7th, David Bushman, President of the AUVSI-SV, assisted by Geoff Chu and Andrew Klofas, spoke to a group of approximately 25 systems engineering students and staff at the International Space University (ISU) at the ISU campus near NASA Ames in Mountain View. Geoff and Andrew demonstrated the rovers' capabilities while David Bushman talked about the rovers' abilities and potential uses, including the ability to operate in fragile environments such as the cryptobiotic soil crusts in the Mojave Desert without damaging them, making them an important tool in investigating similar fragile life forms. He also discussed the Mars Society's rover programs for educational outreach intentions and for the Mars Desert Research Station. David, Geoff and Andrew answered many questions about the rovers and their use in research.

Thanks to David Bushman and Shirley Brim for this report. Below, attendees of the ISU presentation.

September - Outreach Month

We end September logging two rover related outreach events. Chris McKay (the Principal Investigator on the rover project) and Michael Sims, both researchers from NASA Ames, and Khalid Al-Ali from Carnegie Mellon University held a talk titled "Rovers in the exploration of extreme environments on Earth, the Moon, and Mars". The talk was held at the NASA Exploration Center and was specifically open to school children. The audience was taken through a range of topics. From motivation and reports on science done in the Antarctic and Mojave desert and the relation of those environments to the search for life in the Solar system. Through the motives at CMU to develop a rover which is accessible, flexible and easy to operate in science missions, without impact on fragile desert crusts on which we may look for the presence of self organizing patterns left by primitive life. Finally Dr. Sims concluded the talk with a retrospective of Lunar and Martian robotic exploration and the most significant results it yielded. The talk ended with the children taking center stage and blasting the lecturers with questions on all angles of space exploration.


The second event was the Sally Ride Science Festival held at Moffett Field across NASA Ames. The Festival is geared towards girls and its aim is to let them engage in science related activities and workshop for a better part of the day. Discovery workshops and tables were set up by NASA Ames groups and local Bay Area groups. A talk was given by Astronaut Wendy B. Lawrence. The Mars Society Northern California chapter has traditionally been present at the Festival and it did so this year too, with an exhibit showcasing the exploration of Mars, its importance and major results results. Girls were invited to step into some of the problems of performing work in space with our simulation kit. Our presenters also displayed a simple rover autonomy demo with a look under the hood of the control software and a simple teleoperation demo with a laptop monitoring setup. We have also used the opportunity to present the NorCal Rover project and make contact with educators who are interested in future rover science classroom presentations. Here are some pictures from the event.

NorCal Rover Group Outreach Event at NASA Ames

A unique two-week program, under way at the NASA Ames Research Center in Mountain View, is providing specialized training in mathematics and science for California State University, Fresno students eying careers in teaching at schools with a high percentage of minority students.

The Pre-Service Teacher Institute is funded by NASA Ames' Education Office at Moffett Field through a grant to the Teaching Fellows Program at Fresno State and Integrated Space Technologies (IST), Inc. of Huntsville, Alabama. The two-week workshop is designed to increase knowledge, skills and competence in teaching mathematics and science using technology.

The future teachers from Fresno State will be exposed to problem-based learning, mathematics and science enrichment activities at the workshop, which is one of eight such institutes funded by NASA at its centers across the nation and the first one at its California center.

The NorCal Rover team took part in a two hour session with the teachers to present the rover project and it's science and engineering objectives at Mars analog environments on Earth. The latter part of the session was a hands on demonstration of the rover and it's features by Senseta and NorCal staff.

Field Testing Report - Mojave Desert Studies Center

Dr. Christopher McKay, Planetary Scientist from NASA Ames Research Center. and the Northern California Chapter of the Mars Society (NorCal) Rover Team conducted a rover field testing trip to the Mojave desert from 21-23 March 2008. The purpose of the trip was to test the MAX 5 rover, a product of Senseta Incorporated, in field conditions planned for future Spaceward Bound activities and to introduce NorCal Rover team members to rover operations.

The aim of the field testing trip was to perform rover operations and gain insight into further planning of future operation at the Mars Desert Research Station (MDRS) in Utah and in outreach in the greater San Francisco Bay Area. It was also an opportunity for the NorCal Rover Team and Dr. McKay to evaluate the steps related to configuring and options for final purchase of the rovers as well as provide some time for NorCal Rover team members to gain insight into the obstacles which need to be resolved in order to meet the goals in the Spaceward Bound project proposal. Field testing was conducted at the Mojave Desert Studies Center (DSC) at Zzyzx.

The assembly operations and first part of testing took place in the hall of the DSC. First on a plain course later changed into one with artificial obstacles. The outdoors testing took place on several locations close to the DSC. The outdoors testing provided good ground for evaluating rover performance and rover impact on its environment. While the Mojave provides similar ground surface features to the target environment in the Utah desert it must be noted that ground coverage with desert plants is different and more challenging then the one for which the science rover is targeted.

Testing was subdivided into several categories:

Evaluate rover assembly and maintenance procedures in field conditions.

It takes some time to setup the rover and in a noisy wifi environment. Connections can drop between rover and laptop. This could use improvements in wifi robustness (software) and setup time (documentation). The communications issue could be a problem in a school but less so at MDRS. Once the rover is up and running it's fairly stable. Battery change has to be foolproof and simpler. We tested a rover with one camera, we need both of them operational as it will help in driving the rover. There's frame lag and this could use some research into compression and the practical limits of wifi. Battery lifetime could be improved by LiIon in future models.

Test rover maneuverability; in a controlled environment; in the field and by team members with different skill levels.

Driving the rover in the room was not that easy. Using the joystick as a controller is not intuitive at first. When driving there is a number of parameters on the screen which need to be tracked for a successful drive. Moreover in the room watching the rover interfered with the actual testing, training should probably conducted in adjacent rooms or with the operator turned with his back towards the rover. Certain basic rover moves should be introduced right at the start of training. Some of them could also be part of a standard library of moves, i.e. various turns and patterns. This would greatly aid the operator. Also keyboard support should be a high priority. We should come up with a standard rover course beginners should try to navigate.

Test rover capabilities in a desert environment resembling the MDRS Utah location.

During the afternoon we went to the desert and drove the rover in desert terrain. It was easier on that field than in the DSC room. Open ground is much easier for rover control. If both cameras where on it would help. A hammer was placed on the ground with the rover driving over it, not a problem for it at all. The impression is that stones half the size of the rover wheels or plants are not an obstacle. I would help to know the relative direction between the aim of the camera and the axial position of the rover, either by compass or an encoded mount which could be read by software.

Test the control software, laptops and communications operations with the rover.

The software runs smoothly on the laptop no issues there. However at times, perhaps due to wifi latency, the software does not respond in real-time anymore. In the desert it was not observed as a problem, but in a school or a surrounding with a lot of wifi traffic this could be a problem. A wifi sniffer and possibility a change of communication channels may be a solution. Also a wider angle on the camera field of view would be easier for rover control. Screen layout is important too, controls critical for driving the rover should be close to the camera view.

Field test the rover with a simulated science instrument load and evaluate its environmental impact on the desert surface.

Physical impact of the rover on desert terrain was studied. The goal was to find out how much load the rover can carry before disturbance of the ground is registered. The rover, weighing about 5 kg, was loaded first with 3 kg of weight and later with 6 kg without leaving signs on the ground. The loaded rover did also not leave signs on the terrain when going over obstacles. There is ample latitude in loading the rover with instrumentation without causing damage to protected environments. It's impact is less than that of a person walking the same terrain.

Evaluate practical communication range and power autonomy.

Through the tests it became obvious that communication latency could be an issue in controlling the rover, especially if it is compounded by interference from other wifi transmitters. There are some easy workarounds to mitigate this by switching channels or using higher gain antennas in a wifi crowded environment. Fortunately for science studies at desert location this may be less of an issue up to practical limits. The power autonomy is sufficient for meaningful rover sorties once the rover is in the hand of properly trained crews. At MDRS it would be advisable to prep one team member in rover operations ahead of time, this is something where good documentation, solid procedures and intuitive design come to bear. While LiIon may provide more power, it will not substantially change the autonomy of the rover as it stands today. Possible scenarios at MDRS may require the use of ATVs to bring the rover to more remote research locations. This rover evaluation was conducted in dry weather and terrain.

Test potential sciences packages

A Raman spectrometer and GigaPan camera assembly were tested in the field. The GigaPan processing is work intensive and although the results look promising more processing work needs to be done. It is not an instrument that will be easy to use by untrained people. The stitching software is far from perfect but is showing some promising results, processing times are long and it needs a lot of computing resources. Raman spectrometer testing was not conducted using the rover but using samples from the area. Results were satisfactory, issues regardin power and sample contact were discussed.

NorCal Rover Team, April 2008.
Photography (c) by Cornelia Knoepfel.

Training the Next Generation of Space Explorers

Although continued space exploration certainly requires tax payers support - less than 1% of the federal budget is spent on space exploration, i.e. in 2007 this amounts to $1.09 per week per taxpayer - such a program would be impossible without the researchers and staff employed to run it. It takes dedication and consistency to recruit and train the people who make the space exploration program work. And it takes dedication to keep a steady interest among the students to forgo more lucrative technology opportunities and motivate them to take on challenges faced in a space program. While the NASA budget for such activities is often challenged and sometimes cut this rover project demonstrates a positive role businesses can play in keeping the expert pipeline flowing. Google is a company ran by visionaries who understand the importance of a space program. Not only by creating a space related challenge but also through supporting NASA's activities in encouraging students to take engineering and research careers and thus increasing their own opportunities for future hires from this group.

The NorCal rover project was conceived as part of NASA's Spaceward Bound program. Spaceward Bound is an educational program organized at NASA Ames in partnership with The Mars Society, and funded by the Exploration Systems Mission Directorate (ESMD) at NASA Headquarters. The focus of Spaceward Bound is to train the next generation of space explorers by having students and teachers participate in the exploration of scientifically interesting but remote and extreme environments on Earth as analogs for human exploration of the Moon and Mars. One program involves teachers in authentic fieldwork so that they can bring that experience back to their classrooms and assist in the development of curriculum related to human exploration of remote and extreme environments. The second program is to enable students at the upper undergraduate and graduate level (including teachers) to participate as crew members in two-week long immersive full-scale simulations of living and working on the Moon and Mars at the Mars Desert Research Station (MDRS), established and operated by The Mars Society.
The software and rover experiments this group is working on is targeted at both of these activities, one of the rovers will be entirely dedicated to classroom use as a vehicle to explore different engineering and software engineering topics and as a platform for science experiments and simulations.

Since I am writing about the people who care about the eduction of space explorers I should mention something I learned recently while visiting friends at the Naval Postgraduate School in Monterrey, California about an hour and a half drive from Silicon Valley. A total of 33 graduates of the Naval Postgraduate School have become astronauts; more than any other graduate school in the country. So, if you are looking into an astronaut career, the NPS may not be a bad bet. I've been lead through their labs and facilities and the people there are doing serious space science and engineering. And they have among themselves two astronauts who work with them, both veterans of space flight, Daniel Bursch and Jim Newman. Sadly, two NPS graduates perished in the two Space Shuttle accidents; Michael J. Smith aboard the Challenger, STS-51L, on January 28, 1986 and William C. McCool on Columbia, STS-107, on February 1, 2003.

The Space Systems Academic Group at the Naval Postgraduate School established an annual award to an outstanding graduate of the Space Systems curriculum in honor of the two astronauts. The group is looking to raise additional funds for a modest endowment to make the award permanent. If you have an interest in making a tax deductible donation please follow this link.

Why a Rover? Aren't They Already on Mars?

Indeed, NASA has so far successfully operated three rovers on the surface of Mars. The first one, Sojourner was part of the Pathfinder mission. Sojourner, the rover, operated on the surface of Mars for 83 Sols (Martian days) and returned 2.6 billion bits of information, including more than 16,000 images from the lander and 550 images from the rover, as well as more than 15 chemical analysis of rocks and extensive data on winds and other weather factors. Even though science data ranged from geology and geomorphology through mineralogy, geochemistry, orbital dynamics, atmospheric science, astronomy and orbital dynamics - the mission was most importantly set to test novel approaches to the exploration of Mars. Most notably it used successfully a parachute and an array of airbags to accomplish a smooth landing. This approach coupled with a wealth of engineering data opened the path for the next rover mission to Mars.

Scientific highlights of the Mars Pathfinder mission:

* Martian dust includes magnetic, composite particles, with a mean size of one micron.
* Rock chemistry at the landing site may be different from Martian meteorites found on Earth, and could be of basaltic andesite composition.
* The soil chemistry of Ares Vallis appears to be similar to that of the Viking 1 and 2 landing sites.
* The observed atmospheric clarity is higher than was expected from Earth-based microwave measurements and Hubble Space Telescope observations.
* Dust is confirmed as the dominant absorber of solar radiation in Mars' atmosphere, which has important consequences for the transport of energy in the atmosphere and its circulation.
* Frequent "dust devils" were found with an unmistakable temperature, wind and pressure signature, and morning turbulence; at least one may have contained dust (on Sol 62), suggesting that these gusts are a mechanism for mixing dust into the atmosphere.
* Evidence of wind abrasion of rocks and dune-shaped deposits was found, indicating the presence of sand.
* Morning atmospheric obscurations are due to clouds, not ground fog; Viking could not distinguish between these two possibilities.
* The weather was similar to the weather encountered by Viking 1; there were rapid pressure and temperature variations, downslope winds at night and light winds in general. Temperatures were about 10 degrees warmer than those measured by Viking 1.
* Diversity of albedos, or variations in the brightness of the Martian surface, was similar to other observations, but there was no evidence for the types of crystalline hematite or pyroxene absorption features detected in other locations on Mars.
* The atmospheric experiment package recorded a temperature profile different than expected from microwave measurements and Hubble observations.
* Rock size distribution was consistent with a flood-related deposit.
* The moment of inertia of Mars was refined to a corresponding core radius of between 1,300 kilometers and 2,000 kilometers (807 miles and 1,242 miles).
* The possible identification of rounded pebbles and cobbles on the ground, and sockets and pebbles in some rocks, suggests conglomerates that formed in running water, during a warmer past in which liquid water was stable.

Following the path of the Pathfinder mission was the Mars Exploration Rovers mission which landed two rovers (Spirit and Opportunity) in January 2004 on opposing sides of the planet. Although designed to operate for 90 Sols, both rovers continue to operate today almost 4 years into the mission. These rovers were designed as robotic geologists, with the primary mission being the search for water or signs of past water on the surface of Mars. The big science question for the Mars Exploration Rovers is how past water activity on Mars has influenced the red planet's environment over time. While there is no liquid water on the surface of Mars today, the record of past water activity on Mars can be found in the rocks, minerals, and geologic landforms, particularly in those that can only form in the presence of water. That's why the rovers are specially equipped with tools to study a diverse collection of rocks and soils that may hold clues to past water activity on Mars.

A third roving mission to Mars, the Mars Science Laboratory, is scheduled for launch in 2009 and arrive on Mars in 2010. This mission will conduct more complex science and it will have a range of operation of up to 20km from the landing site.

So why more rover science? While we have learned from these missions their ultimate purpose is to open the possibility of a future human mission to Mars, and surely one day to the inevitable colonization of the planet and further exploration through the Solar system and beyond. A human mission to Mars will no doubt rely on robotic vehicles to accomplish science and mission goals, and will in this interaction minimize some of the risks associated with crew's extravehicular activities (EVAs). Having humans and robotic vehicles interact on the surface of Mars changes many of the aspects of rover operation. Normally in purely robotic missions the planners need to factor in the communication delay which can range from 6.5 to 44 minutes for a round trip of commands and responses from the rover. When the crew is on Mars they will have the advantage of being able to operate the vehicles autonomously or in real time and so new scenarios for their use become possible. Moreover these type of human rover interactions will likely take place on return missions to the Moon as well. Therefore one of the primary roles for the NorCal rover operating at the MDRS alongside mission teams will be to explore science and mission operation scenarios where both are involved. The rover has enough computational power, navigational and communications capability and science instrumentation to model a good number of situations. In addition it's twin will be used by mission support teams as a sandbox model available for testing in advance of procedures and program changes suggested or requested by the MDRS crew thereby adding to the realism of the analog environment. Also, while this rover in itself will not test the particular hardware which may one day end on such a voyage it will nonetheless be able to test a good number of design and software architecture concepts which may eventually get incorporated into the actual mission.

Rover Selection Criteria

It took the group a while to turn the general plan of developing a tele-operated vehicle to support crews in a Mars analogue environment into a more detailed set of constraints. We agreed on a set of goals; augment the capabilities of the research crews, with a tool that is flexible and on which we can test different software architectures. The point being on providing standardized interfaces so teams with various backgrounds can develop various functional modules - i.e. a fancy word for adding different science capabilities to the same vehicle. The focus being on using the vehicle to train the future space explorers by having students and teachers devise and use the rover for scientific goals without worrying about the underpinning technical details. Not unlike a relation scientist have with supporting industries today. Rather then designing the rover from scratch we decided the interesting parts are on the interface between the the rover and the science - trading hardware development (which is interesting in itself but better done by people who already have experience in the field) for a platform rich enough to enable development of interesting software and algorithms. Nonetheless, selecting the right hardware in light of deployment in difficult terrain, but also keeping in mind that it needs tobe familiar to students and teachers we devised the following constraints to select the rover.

Top five criteria:

1. within budget
2. tele-operational, upgradeable to autonomous
3. reasonably all-terrain
4. video camera/wifi
5. flexible control unit

Additional specifications:

All terrain should include protection from fine dust and sand and somewhat rain-proof with insulated wires, robust. With one of them we are going into a serious environment, the rover needs to cope with it.

GPS with easy upgradeability. While the first cut is tele-operation, science objectives and future autonomous mode will greatly benefit from a gps unit.

Wifi unless not available, then radio control.

Video camera on a mast, start with one, write software for two, capable of mono or stereo.

Flexible control unit so rover programming is accessible to students and teachers.

Manipulator capability, arm with one degree of rotation

Laser ranger or other ranging hardware in order to keep the rover safe so we are able to give wide access to it yet avoid hazards in the field.

Build or purchase a storage house for the vehicle that can be located away from the hab and has easy open doors that will not need human intervention.

Power management that will allow vehicle to be fully charged for 2-4 hours, go out, come back, and charge itself, possibly shut down while driving to the goal

With this in the back of our minds we started the selection process. At the end, and after comparing side by side more than half a dozen manufacturers that were close to our budget we converged on Senseta's MAX series. The other two very close contenders were Pioneer P2AT and the Segway robotic platform. All of these were good contenders but after weighing primarily the cost and the other factors, we decided on Senseta. It is a good platform, and uses a regular small form factor PC capable of running widely available tools and hardware. If Apple ][ in its days was a great gift for schools, we think this rover could do the same for schools today, yet it is tested in the field and can perform a multitude of science goals at an attractive price. Being a standard PC it is easy to distribute development among teams not having direct access to it as it supports a decent simulation environment in software. Moreover, Senseta is closely affiliated with the robotics group at CMU which had some impressive record of innovation lately, and they were very enthusiastic to provide the initial support to get our group of the ground.