Psyche Mission
16 Psyche is a large metallic asteroid located in the asteroid belt between Mars and Jupiter. Scientists believe it may be the exposed core of a protoplanet that lost its outer layers due to ancient collisions, offering a rare opportunity to study planetary interiors without drilling beneath a planet’s surface.
In 2023, NASA launched the Psyche mission, with an expected arrival in 2029, aiming to capture detailed images and gather data about the asteroid’s shape, composition, and magnetic properties. Beyond its scientific significance, Psyche has also attracted attention for its potential economic value, as its high metal content could one day make it a target for space mining operations.
Project Goal
Design and develop a robotic probe capable of effectively navigating the surface of an asteroid in a reduced-gravity environment. Leverage insights and lessons learned from previous RIT MSD teams, along with external research, to drive innovative, out-of-the-box solutions. The resulting system will be optimized for microgravity operation while remaining fully functional and testable under Earth conditions.
Design Features
Corner Module
The corner module assembly is the heart of the rover housing the winding and locking mechanisms, their two stepper motors, and linear bearings for the extending legs.
Simultaneous Cable Tensioner
This component acts as a three way winch able to tension 3 cables at once when driven by a single steppermotor. To improve the torque output, an internal fixed ring planetary set is used.
Rotating Cam Locking Pin
Legs held under tension are locked in place using a clever pin and slot mechanism. The pin rides on a circular cam keeping it elevated. To release stored spring energy, the cam is spun a short distance allowing the pin to drop into a recess on the cam. A single cam and motor control the locking and unlocking of 3 separate legs.
Frame Structure
The explorer is built on a unique tetrahedral frame made up of carbon fiber tubes. Each of these tubes have 3D printed inserts in either end allowing them to be tapped with standard hardware. The threaded features make for a modular design allowing structural members to be rapidly assembled and dissassebled.
Electronics
Our electrical control system utilizes 3 Raspberri Pi pico micro controllers to handle wireless IO, computation, and motor control independently. Other off the shelf components include stepper motor drivers, a bluetooth communication module, and an 8 channel ADC for handling sensor inputs.
Materials
SLS Printed Nylon-12: Used in components with complex geometries and some strength and durability requirements.
High dimensional accuracy with minimal post processing
Isotropic properties
Possible to make complex geometries without supports
Very strong and durable
Carbon Fiber: Structural components making up the frame of the rover.
Extremely lightweight
Stiff and strong
Readily availible component
Machined Aluminum: Used for the locking cam, extending legs, and spring caps.
For cases where high strength is necessary
Improved wear resistance in moving components
3D Printed PETG: Used for misc. components with low strength requirements
Very cheap
Easy to quickly itterate
Capable for creating complex geometries
Corner Module Assembly with Nylon Components
Individual subassembly with carbon fiber tubes
Extending leg and spring retainer both manufactured out of aluminum
Other 3D printed components
Testing
To test mechanism assemblies, a rotating fixture was developed to allow controlled and repeatable testing. This fixture allows a single subassembly to rotate back and forth about a hinge. Commanding the test fixture to pivot back and forth validates the performance of our design and the implementation of software controls.
A contact pad placed at either end of the test fixture is designed to contain a layer of simulated surface media such as rocks or sand to simulate performance on loose surfaces.
Acknowledgements
Group Members:
Peyton Dennis
Christopher Nokes
Sowntharya Sritharasarma
Samuel Slember
Allan Yang
Team Guide: Prof. Gary Renz
Client Contact: Cassie Bowman