Overview:

Below is a brief the results and findings of Crew 60 to the Mars Desert Research Station in early spring 2007. Crew 60 was the first all-student MDRS crew from a single university. See http://www.gtmars.us/ for more detailed descriptions of our results.

Logistics:

Purchasing and keeping track of food and supplies for six growing college students, or any number of crew members for that matter, is a unique task. Dividing dinner meals among the crew members and compiling the ingredients made it easier for the Logistics Officer to create a shopping list and cooking/cleaning schedule. In an attempt to eliminate the ambiguity of shopping lists from previous crews, a complete list of all foodstuffs was created. This list was sent to the next crew and uploaded onto the Hab computer in hopes of its continued maintenance.

Lessons learned include freezing meat and vegetables already divided into meals rather than in bulk and thawing more than necessary at a time. Perishables and meals that have perishables need to be eaten during the first week.

Health and Safety:

Allergies, dust, heat, and the low humidity seemed to be the cause of most of health issues faced on Crew 60. Several members of the crew faced fatigue/headaches and/or clogged/bloody noses, all of which were only minor and were solved with an occasional nap or tissue. Being well fed and rested on schedule are essential for having everyday health and energy. In dining/group work area was great for morale and spirit, which were always strong.

The portable first aid kit was restocked and the HSO cabinet reorganized. A fire extinguisher brought out by the next crew will be placed in Engineering near the generator and fuel.

GreenHab:

Maintenance of the GreenHab was focused on keeping the plants alive. Temperatures inside the GreenHab varied from 60 degrees Fahrenheit to 100 degrees, with the fan and heaters running as necessary. The plants required water at least once or twice a day. Dried out leaves were pruned every couple of days and the plants were rotated about once a week. The plants closer to the wall of the GreenHab were driest. The solution of building another shelf on the other side of the GreenHab was proposed. Plants moved from the back are more easily accessible for pruning and watering and should not dry out as much.

GreenHab Systems Improvement:

• The submerged Rule pumps in the gray water reservoirs were no longer operational. They were replaced with non-submerged Shurflo washdown pumps, mounted on top of the gray water reservoirs, each with a submerged screen filter for debris and a fine cylindrical screen filter just upstream of the pumps. The pumps were wired to the existing circuits for the submerged pumps.
• Tank 1 was found to be tilted towards the outside of the Greenhab, such that it spilled before water could transfer to Tank 2. The tilt seemed to be due to sagging of the plastic tank. The back of tank stand was raised with an automotive jack and wooden spacers were placed under the feet of the stand. The tank now drains properly.
• The sumberged 500 GPM Rule bilge pump in Tank 4 which pumps into the Toilet Supply Tank stopped working during crew 60's rotation. It blew a fuse, and when the fuse was replaced, that fuse was blown also. It is suspected that the water seal on the electrical system failed, and the pump shorted across the water, but this has not been tested. The pump was replaced with a 380 GPM Rule bilge pump. These pumps seem to fail quite often; along with the three replaced by this crew, three more were found in the Engineering trash pile. Perhaps these should be replaced by more reliable pumps in the future.
• The Toilet Supply Tank was cleaned. It previously contained a large amount of sludge and debris.

Science Research:

Astronomy: A remote control for the weather needs would be useful to ensure that astronomy research can be conducted as desired.

Geology: A magnetometer and conductivity meter were transported from Georgia Institute of Technology to demonstrate the feasibility of using the equipment with the surface suits. The devices were difficult to use and bulky to carry around on top of the surface suits. The gloves further complicated the operation of the devices. The metal in the suits may have affected the measurements.

A location close to the Hab was surveyed as a test. Then, an extensive survey was conducted around the high frequency (HF) antenna to determine if the conductivity of the ground surface was low enough to contribute to poor radio transmission. A peak in the data was detected nearest to the Hab on the north side, and it is believed to be the septic tank.

There was not enough time to conduct measurements beyond areas close to the Hab, and the lack of ATVs limited the mobility of the team. If similar equipment is available in the future, the geology team should survey larger areas and formulate a goal. Also, collaboration with the Remote Science Team would be beneficial.

Human Factors: Crew 60 participated in several human factors studies, including several cognitive ability and mood tests coordinated with saliva samples. The restrictions imposed the day of a saliva test were often inconvenient and the tests took more time than hoped by the crew, but it is hoped that the data will be good.

Radio Research:

A number of efforts were made to demonstrate the use of amateur radio at MDRS. The Automatic Position Reporting System (APRS) was used in combination with GPS units to allow automated tracking of crew members on EVA. A digipeater and crossband voice repeater were deployed on Skyline Rim to increase the range of voice and APRS communications. A high frequency antenna was also set up to allow direct radio communication to Atlanta for outreach activities.

The use of APRS is an ongoing project for Georgia Tech crews. This year's efforts featured near real time crew member tracking in Google Earth and via pictures posted to a website. The system was successful; as long as the crew was in range of the Hab radio during EVAs, their position could be tracked real time at the hab and near real time on the web. It is recommended that other crews use amateur radio to increase the range of voice and data communications.

The digipeater and crossband voice repeater deployment on Skyline Rim was a partial success. Communications from the rim to the Hab were crisp and clear, even with low power settings. The digipeater and crossband voice repeater worked correctly until they ran out of battery power. The radios were powered by a battery with a solar cell charger. The weather was poor, and the solar cell did not provide sufficient power to run the radios, so the repeater system did not work during EVAs. It is suggested that future missions look into deploying radio equipment at Skyline Rim, pending approval from the Bureau of Land Mangement, because of the incredible radio coverage available from that location.

A high frequency radio and antenna were set up at the hab to allow direct radio communication to Atlanta for outreach activities. The antenna caused a number of difficulties because it had a tendency to fail in high wind conditions; this was due to the crew's lack of experience constructing this type of antenna and extraordinary weather conditions. After repairs to the antenna, contact was made with Atlanta Mission Support only one out of several times, with weak signal. Resistivity measurements of the ground around the antenna suggest that the soil absorbed a significant portion of the power being generated by the radio, causing the signal to be weak and affecting the antenna tuner's ability to tune the antenna for many of the radio bands. Future crews desiring to use HF radio should carefully select their antenna, taking good ground planes, soil treatment, and highly directional antennas into consideration.

Hab Systems Improvement:

• The marine toilet was disassembled and cleaned. The impeller and masticator were both completely clogged with toilet paper, which had been causing the toilet to eject water and waste when it was flushed. The toilet paper was removed, and the toilet now functions properly.
• The line to the external potable water pump was tested with a multimeter. It had been reported to have a fault, but simply testing the line with a multimeter revealed no problems, so further testing is required.
• The path up to the Musk Observatory was widened and leveled to an even grade. For future work, hand rails can be constructed for added safety and convenience.
• The One Meter was expanded to include temperature and water meter sensors. Currently, it logs the temperature in the loft and the use of potable water. It is hoped that, before departing the Hab, there will be a temperature sensor connected in the GreenHab, as well as the two water meters there. A 24VDC-to-5VDC power supply is also hoped to be installed. The Telnet link of the One Meter is currently being investigated for remote monitoring of the Hab.
• The crew is in the process of bringing the 24VDC-to-12VDC system online, with appropriate fuses and safeties. The wiring is expected to be completed tonight, with the system being brought online Saturday morning.

Engineering Inventory:

A complete inventory of the engineering area was undertaken. An Excel spreadsheet was created, and it contains the following columns: line item number, location categorized in three levels, name, quantity and extra notes. The Excel file contains six tabs where each tab is sorted by different columns. Most items were labeled with its line item number using a piece of masking tape. Items that were not labeled were consolidated in labeled bags or containers.

This engineering inventory is a living document, and the "Admin" tab is intended to log the revisions made to the document. It is the wish and hope of the inventory team that the equipment will be used and stored properly.

Emily Colvin
Commander, Crew 60