Our final robot digging up regolith!
Testing our robot before the final competition!
Project Overview
"Building a Lunar Base: NASA is working to establish a permanent human presence on the Moon within the next decade to uncover new scientific discoveries and lay the foundation for private companies to build a lunar economy. Artemis is the twin sister of Apollo. The US will go back to the Moon. This time we will build a community. Can we build the necessary infrastructure?"
I worked with a team of three other students in MIT's course 2.12 Introduction to Robotics (Team Cambridge Dynamics) to modify an existing robot base to excavate, transport, and dump "lunar regolith." Our final design was a robot with a front scoop that could raise and lower using lead screws, tilt using winch and drum, and dump out regolith using a rake and lead screws. Our robot was tele-operated using a joystick.
Final competition stage layout. The robot had to start in the starting box, drive around obstacles to collect regolith, and drop the regolith into the collection bin,
The base robot that we used as a foundation for our robot
Collection Concept Ideation
I suggested our first concept for a regolith collection mechanism which was a device that would suck up and shoot out the regolith like a vacuum. The vacuum was a unique idea and could have been improved with better sealing the mechanism, but overall it wasn't collecting regolith fast enough and it needed to be plugged in which we couldn't do on the moon. Therefore, we began testing other concepts.
A bucket design was promising since it could collect a lot of regolith at once.
VacuumTest.MOVTesting the prototype of my vacuum idea
BucketTest.MOVTesting a bucket scooping mechanism by hand
Bucket Robot Test.MOVTesting a bucket in front of our robot
Driving Discussion
We tested driving over regolith and it had difficulty with the given tires. They lost too much traction when they drove over the regolith. It would be a big issue if our robot got stuck in the regolith during the competition, so we opted to swap the tires for larger ones.
Driving Test.MOVDriving over regolith test
Team discussing driving test results and deciding to switch tires
Prototyping and Development
Our first prototype consisted of three subsystems: rake, bucket lifter, and chassis.
I worked most on the construction, mounting, and testing of the bucket mechanism. I also did the wiring for the motors.
Ultimately, we faced difficulties with the rake. We found that it was not really necessary to have a rake to pull regolith into the bucket. If we drove into the mountains of regolith, the buckets would fill well just from driving. Actually the rake more often got in the way and made it more difficult to collect regolith. It was a helpful concept for pushing regolith into the bucket, though, so we changed the rake to be a curved shape that sits on the inside of the bucket and does not help to rake regolith in, but does help to rake regolith out of the bucket.
Tilting Mechanism.mp4Tilting mechanism before winch was installed
Lifting Mechanism.mp4Lifting mechanism
My wiring!
Our winch system
Team discussing troubles with our original rake idea
We tested removing the rake entirely, but that left valuable regolith inside of the bucket
New Rake Design.mp4We ultimately redesigned the rake to not pull regolith into the bucket, but to push it out of the bucket into the collection bin. Here we are testing our new curved rake.
Final Competition
Our robot ended up collecting the most regolith out of all 6 teams in the competition! We collected over three times the required amount with time to spare and the amount of regolith that we collected actually broke the scale! We were very proud of our robot's performance and our work as a team.
Final TestingIn our final run-through testing before the competition, we were able to collect 3 kg of regolith in only 3 trips.
Contact
508-404-3168 | leplatt@andrew.cmu.edu | Pittsburgh, PA | https://www.linkedin.com/in/laurenelizabethplatt/