Unicycle Master's Degree in Engineering Thesis

So, I’m a Mechanical Engineering graduate student going for my Master’s of Science in Engineering, and I have been riding unicycle since about 2007. I primarily ride Muni and around the neighborhood.

I am at the point in my program where I need to decide on a thesis topic… I have decided that if I am going to pour a whole ton of energy into something for the next year or 2, I want it to be something that I’m passionate about.

Why not do it on something related to unicycles I thought? I’m posting here to see if anyone has any ideas on problems or topics related to mountain unicycles, or unicycles in general that might be thesis material. I need something mechanical in nature, and am hoping to include numerical simulation, mechanics, materials, or dynamics into my thesis. The area of biomechanics and the interaction of rider to unicycle is a possibility as well.

If you anyone has any ideas, or wants to suggest unicycle topics that getting an answer to would be beneficial, please let me know. Don’t hesitate to fill up this thread with any ideas you have!

Thanks in advance!

Can you design a tyre that is immune to road camber? You could examine weight, construction, size, sidewall characteristics, shape, tread pattern, materials, and the effect of different pressures and rim width/style.

I’m thinking 36" but it could be any size I guess.

Um, I’ve seen these kinds of requests here before, but never from someone who is in an MS mechanical engineering program.

That’s actually an interesting one. At first it sounds like a tire-stuff question, which it is, but it’s really about unicycles as well. Other vehicles (bicycles or anything with multiple wheels) don’t need to worry about camber the way we do. We have to put in counteracting energy with each revolution of the wheel to balance the camber against the line we’re trying to ride. It could be an interesting topic to study, if you think it would be fun to learn a ton about tires and tire shapes.

You could work with existing tires (easy), and possibly with experimental tires by modifying some yourself. Who knows, you might even be able to get a tire company involved and help you with prototypes?

While being “immune to road camber” is probably not realistic, a study about “what type of tire(s) are best suited to riding on cambered surfaces on a single wheel”. Is it more about the cross section of the tire? Or the tread itself? Or the construction of the tire? Probably a combination of all three plus tire pressure. I know pressure affects how a tire reacts to camber.

It’s not like he’s asking us to do his homework for him; he’s just looking for ideas. My dad was a mechanical engineer (automotive, now retired). The world always needs more engineers!

That one is very simple. Make it as skinny as you can to keep the contact patch as close to the centre as possible.

A CVT-geared hub would be great!

studying how a unicycle steers, quantifying how how that steering is different from bicycles, and how to how to capitalize on those differences to develop a unicycle tire would be a great read at the very least. FYI, here’s a good overview of motorcycle steering with a description of camber thrust steering - what is the main, but not by any means the only way unis are steered.

Thanks everyone for the response! I have actually thought about the camber topic, since it is something I’ve experienced firsthand and wondered how the negative effect could be reduced.

Don’t hesitate to mention some more. I’m compiling them into a list and doing some preliminary research. No need for anyone else to do my homework. :slight_smile:

Ungeared muni wheel design that takes into account the fact that it’s hit hardest in cranks-horizontal orientation and needn’t be as strong in others.

What about looking in more depth at muni riding, how terrain effects balance, where and how much the stress forces on the unicycle are in different situations (hops, uphills, downhills) and if any design improvements could be made to improve performance or reduce weight.

Essentially riding, and getting other people to ride, lots and lots of muni with a unicycle covered in sensors and then number crunching the data.

Good place to start if you haven’t seen it yet:
http://rspa.royalsocietypublishing.org/content/466/2118/1849

I see that Sharp worked with Hans Pacejka, who is pretty much The Man when it comes to pneumatic tires.

There’s been lots done on self-balancing unicycles lately, maybe especially because a very simple control algorithm turns out to work fine even though the equations of motion look pretty hairy. You might want to be fluent with that stuff even if you don’t care about the self-balancing part because, you know, science.

He said M Eng, not post-doc! :slight_smile: (Seriously, the common gotcha for theses and dissertations is trying to do too much.)

I don’t Muni, so I could be completely wrong here, but I read that with mud, you either have to pick a skinny tire to cut to the bottom, or large tire to “float”, so maybe you could do something with that.

Maybe someone could chime in on whether this is a real problem or if this is just my memory making up things.

V Frames

I find V-frames fascinating. Turtle’s V is especially beautiful (http://www.unicyclist.com/forums/showthread.php?t=91749). Could there be muni benefits to a V-frame, perhaps allowing a greater degree of control were it to be set up differently from a road uni?

Fulfill everyone’s unicycle wish, make a cheap geared hub.

Crank arms that can easily adjust from 110 - 127 - 150 during a ride without having to use a pedal wrench. It would be cool if the pedals were removable. Just pop them out of one hole into the other.

Agree. Or a pedal crank with an internal slide to adjust length. You’d make a million bucks!

Other ideas: a unicycle that coasts.

Unicycle rims that never “taco” on jumps (maybe a mag wheel unicycle that works).

See Adventures in Freewheeling.

As far as muni is concerned, a skinny tire is out if you want to enjoy the ride, so it doesn’t help. Maybe for Road?

The main benefits of V frames are rigidity, and the possibility for more flexibility in adjusting the fit.

What you don’t get with a V frame is a better connection between the frame and the wheel. It all still goes through your bearings, which is perhaps the weak point in unicycles from a structural point of view. We have great hubs, great bearings, but we still put an awful lot of twisting forces through that little interface. If there were a way to shore that up, it might bring power benefits over unicycles that flex as you pedal hard.

Suspension and adjustable cranks would be fun things to model/look at. Especially the forces involved and merits of various designs. I’m thinking a channel with stop ever 5mm instead of just two drilled holes.

That’s what I thought, but I remembering reading that somewhere, so I threw it out there in the oft chance it was true.