NASA Robotic Mining Competition 2021-2022
Systems Engineering Paper
NYU Tandon School of Engineering participates in the yearly NASA Robotic Mining Competition with its Robotic Design Team. The main objective is to construct a rover that is capable of transverse rough Lunar terrain (simulated with fine regolith at Kennedy Space Center in Cape Canaveral, FL) and to excavate to 50cm depth to collect and store a sample of regolith.
I held the position of mechanical technical lead for the excavation subsystem. I was also in charge of collaborating with electrical, and computer Science technical team leads to attain a complete integration of my subsystem.
The main objective of the NYU Robotic Design Team for the 2022 competition was to deliver the purest sample of regolith collected at 50cm depth. In other words, we did not focus on quantity but rather on the quality of the sample collected. This played a major role in the design and philosophy of the rover, which will become apparent as I break down the design.
In order to achieve the goal of obtaining the purest sample of regolith, I lead the design of a modified auger that was able to excavate to the desired depth by turning clockwise and then collect a sample at the desired depth by turning anti-clockwise. The main challenge that the design encountered was the size constraint of the rover dictated by NASA and the required depth to retrieve the sample. As NASA dictated, the rover could only be 60cm wide x 60 cm high x 100 cm long, this meant that if the auger was to be placed at a vertical position, the wheels had a minimum 10cm radius, and the linear actuators had a stroke of their entire length, you could only reach 50cm but couldn’t retrieve the material found further than that. In order to solve that issue, I lead the design of a pivot mechanism to store the auger during transportation and deploy it during collection. To deploy the modified auger, we used two parallel linear actuators that carried and directed it.
To carry and rotate the auger, we designed a mount that could firmly attach to the linear actuators while also allowing the auger to turn freely. As seen below, the red body connects the linear actuators with the modified auger. It wasn't symmetrically designed because, in order to have both linear actuators facing the same side and therefore have both of their motors at the bottom facing forward, one of the connections of the linear actuators had to be done on the outside while the other on the inside. The two internal grey discs at the bottom of the red mount are ball bearings that allow the modified auger to turn while remaining tightly fixed to the support. The orange and yellow disks are caps that prevent the ball bearings from sliding down and secure them to the mount. They were designed with self-locating features for faster assembly and tighter interference fits.
In the third image, you can find me holding the prototype of the linear actuator and auger assembly. I am holding it from the left-hand side.
The pivot was designed to be strong enough to carry the entire weight off the linear actuators and auger and small enough to not collide with the ground while stored. The pivot point consisted of two main parts, the motionless motor/gearbox to pivot the linear actuator and a mount that holds the linear actuator and its motor in place.
The interior of the linear actuator mount was designed with DFA in mind so that quick repairs would be possible, but it was also tight enough to prevent any unwanted movement.
Below you can find the modified auger, auger mount, and pivots fully assembled into the chassis and wheels, ready to be shipped out to NASA.
Unfortunately due to some delays in shipping of key raw material and components, some parts had to be manufactured out of wood, instead of aluminum or steel, while others were not able to be installed in the robot. Even though this was outside our control, we learned to plan much more ahead, to have earlier deadlines for purchasing material, design and manufacturing, and to have a plan ready to be implemented in case any component does not arrive.
In addition, below you can find videos of the three mechanisms working before they were installed in the prototype; the first shows that the pivots can bring the auger to the required angle, the second shows that the auger can freely rotate without unwanted movement, and the third shows that the linear actuators can carry the weight of the modified auger.
Unfortunately, due to electrical issues during the competition, the robot did not receive power during the designated time slot provided by NASA, therefore preventing us to demonstrate our subsystems and the behavior of the robot. Even though this was disappointing and not the result we were expecting, we came out a lot stronger, having a much deeper understanding of robot design, manufacture, and testing, and it left us with an unbreakable desire to improve and reinvent ourselves and our robot to have a chance at winning the competition the next year!
Thank you for reading,
Please reach out if you liked the project, more about me and my contact information is in my About me section on the top right!
