Atmosphinder Midterm Research Report

Mars Desert Research Station Crew 261

May 7, 2023

By: Erin

Atmosphinder arrived, was built, and iteratively developed throughout testing milestones this week. Quantitative and qualitative testing was performed on both the prototype and electronics. The plethora of testing and work resulted in this key learning:

-> Tensegrity robots, in combination with rigid structural components, have merit for use in extreme environments, such as Mars.

The reasons for this is because:

1. The compliant structure nature of the structure is able to adapt to the uncertain landscape - as seen on EVA-9, EVA-4
2. Rigid structure enables the robot to harness and endure the power of the wind and the environment - as seen on EVA-9, EVA-6

Overall, Atmosphinder performed as expected for an early small scale prototype. It was enthralling to observe the interaction between the robot and its environment! The structure passively waned as gusts of wind occurred. The mechanized sail trim motors functioned better than expected to control the direction of the sails. Finally, the ultra-bright Neopixels were dazzling and visible outdoors. Surprisingly, the three ball bearings (sealed) have not encountered any challenges regarding jamming from dust / sand.

Areas of improvement include: The known weak pieces did break, while the known stronger pieces did not. Duct tape and hot glue was pinnacle to the repairs. Some tubes rotate in place in the 3D printed pieces, which was detrimental to the sail frame structure wind testing. A missed opportunity was swapping the blades on the hoof sub-assemblies for a smoother revision, which could have assisted in a smoother rolling gait, and thereby further rolling distances.

Additional information, including graphs, maps, and photographs can be found at: http://robotzwrrl.xyz/atmosphinder/

Code and datasets can be found at: https://github.com/RobotGrrl/Atmosphinder

Extracting the above key learning from the testing and work demonstrates the value in pursuing the idea further for a higher fidelity prototype, perhaps via an internship at NASA JPL.

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The electronics of Atmosphinder has been used to data log environmental sensor data at 1 Hz on EVAs. These datapoints are mapped to GPS coordinates. The sensor data now includes: Anemometer, Pressure, Humidity, Temperature, PM 2.5, PM 10, NH3, as well as: battery voltage, servo motor rail current, and information related to an internal state machine. The sensor data can then be graphed and plotted on a map using a web app developed by Robot Missions Inc. The addition of sensors grew each day, making use of the soldering equipment in the RAM.

When interacting with the Atmosphinder electronics, the key learning was:

-> Human-Robot Interaction (HRI / HCI) is challenging when fully suited in astronaut gear

This key learning was noticed when reaching for the electronics situated in the electronics payload bay of the robot, which was limited by the astronaut helmet. Activating the electronics has to take into account the astronaut gloves. Something that worked well were separate status LEDs blinking to show the data logging, GPS fix, and microcontroller status is nominal, as this can be checked at a glance. A stretch goal hypothesis to test is mentioned below as an experiment.

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While on the mission, the next objectives for Atmosphinder is to gather additional information and observations in order to serve as design and testing requirements for future development on Atmosphinder. This will be done by visiting locations with features analogous to the Mars south polar region.

In the Mars south polar region, there are three major geological features:

• Erosion features
• Ridges
• South Polar Layered Deposits (SPLD)

At the Mars Desert Research Station, regions of interest about those geological features include:

1. Glistening Seas (eruptions)
2. Erica's Hill (erosion features)
3. Barroom Outcrops (SPLD)
4. Skyline Rim (SPLD)
5. Additional locations may be added

The remaining EVAs will embark to those locations. Atmosphinder half-sized robot prototype will join for the journey. Limited dynamic testing will take place. The electronics payload will continue to be used to collect environmental sensor data. A stretch goal will be to implement IMU data logging at a fast frequency to be later used for training a model to recognise the terrain type.

For background: Atmosphinder's destination on Mars is the south polar region to observe the CO2 gas jets from the surface level and contribute data from these activities to the global Mars climatic model. The research conducted at the Mars Desert Research Station is in line with these goals by demonstrating an original robot prototype and by logging environmental sensor data.

A remaining technical stretch goal for Atmosphinder development and testing is a Human-Robot Interaction (HRI / HCI) experiment involving fully suited astronauts controlling the robot by showing coloured signs in front of the robot's camera. This is dependent on a firmware update for the embedded computer vision camera, which is pending a response from the developers.