Vehicle Blog Post #2

For this blog post, my team and I are moving forward with designing a prototype based on our definition statement:

Our team must design an efficient transportation method on a foreign celestial body, both without wasting excess energy and without wasting time, capable of a 5-kilometre-long round trip on Ganymede, one of Jupiter’s moons. This vehicle must handle extreme conditions including temperatures as low as -180C, low gravity(a tenth of Earth’s), rocky terrain, and interference from the planet’s magnetic field affecting electronics.

In order to figure out how to solve this problem, we went through quite a few different ideas for a vehicle that would work:

One of the ideas we thought of was a Jet Pack. A Jet Pack could actually work pretty decent on Ganymede mainly because of Ganymede’s extremely low gravity, meaning you wouldn’t need too much upward thrust to keep it in the air. However, building a Jet Pack is kind of out of reach in terms of what we can make, especially since no Jet Packs actually currently work on Earth. Another constraint we would have is the extremely low temperatures on Ganymede, meaning that along with the Jet Pack we would need to design a special suit that could withstand the harsh elements.

Another idea we came up with was a sort of drone/helicopter. A drone or helicopter could have a couple of advantages, mainly being that since Ganymede has an atmosphere and oxygen, it could be able to fly around well. The problem with this is that it is possible to be inefficient due to the lack of gravity and the rotors spinning so fast, or it could simply just not work well due to Ganymede having a tenth of Earth’s Gravity.

We ended up settling on a design of a car with 4 axles (meaning 8 wheels), with the body similar to that of an SUV, extreme amount of suspension travel to help mitigate the possible jumps of the car due to the low gravity, and in order to help keep the car on the ground, we have added 4 roof mounted thruster which can help prevent the car flying off into space. Pictured below was our rough sketch for our car:

Additionally, we brainstormed some ideas to help us with the testing of our robot. We wanted to test our robot mainly for its ability to traverse rocky ice terrain as this is what it will be facing on Ganymede. I will talk more about the specifics of our test further down in the blog post, but we decided to brainstorm a few ideas that could help our robot traverse this terrain. We decided that putting chains, or spikes in the tires could work, as chains are a very effective way that trucks and cars use to traverse through Icy terrain on Earth.

Another thing we brainstormed was using low amounts of Psi in the tires of the car as typically for traversing rocky terrain, off roaders on Earth have very little Psi in the tires as it allows them to climb up rocks easier.

We also brainstormed that it would be possible for our vehicle to have a combustion engine as there is oxygen on Ganymede. We think that pairing a combustion engine with a hybrid system could be very effective as you would have the low RPM torque that an electric motor offers, while still having High RPM power of a combustion engine. While we will likely not be able to implement a combustion engine when we build our prototype, it is still something to think about if this car was really implemented. Another benefit of the hybrid system is that the car could be very efficient and able to swap between and combine the two power trains simultaneously and apply power where needed.

Our Prototype in Cad:

As a part of this assignment we had to create a more concrete prototype over our rough sketch about what this car would look like:

This is just the start of what we think our prototype should look like. If you look at our original body, you can see how we keep the SUV style of body. We do however, ditch the 4 axle system as currently we don’t think it is feasible to make, and a 2 axle system is easier to make. We will be putting this body onto an RC car that we have sourced.

Here is a mechanical drawing of this vehicle:

Here is a Bill Of Materials that we will need in order to create our prototype:

BOM:
PLA For the shell of the car
Velcro Link
RC car (Already have)
Gorilla Glue Link

Next, my team and I created a statement for what our vehicle design is intended to test:

We are testing the vehicle’s capability of navigating icy and rocky terrain, conditions similar to those of Ganymede.

Additionally, we created a statement of how we intend to test it:

To test this, we are considering small ice cubes, mimicking the frozen surface-level terrain, as well as dirt and larger rocks to help mimic the rocky and icy terrain found on Ganymede.

We will specifically be testing for its grip on ice, off-roading capabilities on rocky terrain, and efficiency. In order to test for efficiency, we will test if the vehicle needs to use up more wattage on rocky and icy terrain versus on solid terrain. To test its grip on ice, we will measure its stopping time and distance on normal surface versus on ice. In order to test its off roading capabilities, we will create a series of off roading challenges, each getting more challenging, and seeing if the vehicle can drive through it.