AUV's are in a sense just an underwater rover. AUV's are already real things, often times connected by wires to boats and equipped with lights, cameras, and some type of propulsive controls. On Ceres, we will need more than that. We will need methods of collecting materials and samples, as well as being able to map 3D scans of the underwater terrain. On top of that, the AUV has to get underneath the frozen ice crust. We still don't know how deep the ice is, so we have to speculate that it may be anywhere from 2 to 12 miles deep. This is a problem for getting any underwater vehicle there period. Not to mention getting the AUV's to Ceres in general. Unlike the orbiting rover that can just float in orbit until it wants to land, this will need to land and be able to set up a stable platform to drill into the ice.
It is interesting though that my process initially didn't begin with the AUV itself, or even the transport and landing assembly. It began with considering how this thing was going to barrel through miles of ice. Now, ice drilling has been done on earth using diamond bits and huge drilling compounds. But planetary drilling is still a thing of speculation and distant future. But the technology that we may deploy in the future is still current. Drills, Nuclear, and Laser technologies all exist today and would be feasible to consider as ways of cutting through ice.
This is just a starting point, and really an important one. I am not a scientist, so iterating many ways that a nuclear torpedo might work really is something that isn't necessary for process to evolve. My only thought at this point was, what ways are possible, and out of those which makes the most sense. This goes for both the method of drilling, as well as the the function of the drill assembly and legs.
By this point in time, I have an idea already that the nuclear heated torpedo will make the most sense, it just heats up and descends through the ice at its own weight. The question became does this thing land and orient vertically, or horizontal and then re-position? The middle iteration explores the re-positioning method. The less moving parts for this thing the better, it would only add to potential failures or complications, so I chose to mix the landing gear from version one and nuclear heated torpedo from the middle. These are relatively low iterative designs because this is just the harness for the real goods. The AUV's, and in our case, the goal is to have three, not just one.
The next consideration kind of backtracks a bit. The method of getting the nuclear drill in place and distributing the AUV's is in place, but I still haven't considered the method of delivery to the planet Ceres. This is a crucial stage and part of the design because ultimately if this stage wasn't considered, these AUV's may not even have a chance in the first place. So, we have to reconsider Ceres and its properties. Ceres escape velocity is extremely low, which means that leaving the atmosphere is really easy. That is good, except we are trying to land on it, which means it is very difficult to do when approaching from an extremely high speed.
I considered 3 stages of deceleration. Stage 1 is on board propulsion that really controls the terminal velocity during the approach to begin deceleration and landing. The front shield propulsion will burn until it is empty and then will discharge the front shell. Stage 2 controls yaw, pitch, and rotation. This will allow the capsule to be steered and aligned to its approximate landing site.. Stage 3 cuts parachutes, expands landing gear, and uses it's powered decent propulsion to land safely.
Keep in mind, at this point I have only established a platform to work within. I now have a volume and geometry to fit inside of the torpedo capsule that will shuttle the AUV's safely to the ocean surface. Most importantly, I know how this thing will descend to the Cerian surface, I know how it will deploy the nuclear torpedo, all that is left is to design the actual AUV's which can be nearly anything that I can imagine. I may iterate 3 of the same that work separate, 3 that work together, or two that work relying on a single transmitting one. Too be worked out soon.
As I moved into the second phase of designing these little underwater bots, I already had plenty of constraints and components that needed to be there. Looking extensively into current AUV's, it was apparent that the arrangement of propulsion and propellers could really vary, depending on what you needed. I used the "chaos brush" technique to start on some rough ideas. This was a brush pallet that I created that was a mix between a microscopic antarctic shrimp looking microbe, and an actual 3D scanner. Although you cannot really see either in the combined brush, it does lend to this somewhat mechanical/shrimp like hybrid, which ultimately gives the concept art the feel that it ends up turning into.
The one thing I did differently was that I chose to make this component symmetrical, to a degree. I had the torpedo cylinder as a constraint so it only made sense that it would effect the way this thing would look. Working off of an axis down through the center also allowed me to utilize one vertical propulsion that could literally just make this thing move up and down.
Also considering the function of this thing as being autonomous, meaning it has to think on its own. It actually needs to be pretty simplistic in its functions. I envision that the landers would all sprawl out together, and the claw collector would just have one motion that would dig and collect samples into a spinning container cylinder located at the base. Another important part is the 3d scanner unit located at the top. This would map geological information and transmit it to the surface where it would then relay it back to earth or whatever research base that it may be functioning from.
So at the end of the day, I end up with one giant landing mechanism with a nuclear heated torpedo that transports two little underwater rovers that are sent to collect information, seek signs of life, and determine other characteristics of the water. All in all this was a very quick and chaotic process that I am rather pleased with. I think that beginning to embrace this random way of designing informed functioning mechanisms is really an interesting approach, and I am anxious to keep expanding and exploring new ways to conceptualize the future.