Touch The Pavement

It was hard to get any of these type of pictures to come out right, but they are cool enough to post here anyway.

Pushing The Envelope

All right, we got some new pics of the TreMoto tearing it up on every kind of surface you can imagine. From dragging your knee on the pavement,to sliding all 3 wheels on the gravel, this thing amazes us more and more every time we refine the design.

Still poundin'

Somehow we fell completely off the blogging bandwagon. In the meantime, we completed a prototype.


Not bad, if I do say.37 degrees of lean isn't bad, but we missed the design target. Time for a Hyper-powered v2.0? Perhaps a Kawaski 4-cylindered 3Z1?

New Pics and Equipment

Check it out.  Eddie replaced the wooden placeholder suspension pivot with the billet aluminum one James made for us.  He then attached the rotary dampers.

Attaching the rotary dampers caused even more weight to hang below the roll-center of the bike, which is already higher than the stock roll-center by the nature of the design. The increased weight below the roll-center caused an increas in the pendulum-like effect our front suspension has regarding on-center balance.  This pendulum effect allows for feet-up stops and even more, as evidenced in the picture above.  We noticed this when we first had it on it's wheels and it not only helps the bike balance at on-center, but also allows for the bike to be supported by the rider's legs at a much larger lean angle when sitting still.  There should be no problem picking the bike up from its roll-stops if it is accidentally dropped.  This unintended consequence of our low center-of-gravity/mass-centralization design philosophy is pretty sweet.  The balance is easily upset by very small input, so hopefully it won't negatively effect our turn-in responce too much.

We still need to get our steering linkage parrallel and equal o a-arm length before it will be ride-able, but otherwise, just time and money stand in our way.

Turns out we got 3rd Place in the design competition.  Sucks, but no biggy, as I heard the Fed-Ex guy got a bad grade on his parcel delivery business idea while in school here.  They told him his idea of central hub airports was unrealistic, parcel delivery was a natural monopoly left to the governement, and he should have done an experiment about bearings instead.  Okay, maybe I made the last one up, but still thats the story.  Maybe our incorrect steering geometry caused this, but seeing as how even the PhD's didn't pick up on this during the entire lead up to the contest, I don't feel stupid for not noticing it sooner.  We expected some steering mess, but were unsure of how much of a problem it would be until we got a physical prototype to see in action.  A pair of left and right parts to go on the spindles should rectify this problem easily.

If a picture is worth a 1,000 words...

9 x 1000 = ...well you do the math, click the pictures to see full size, I'm going to shut up now and let the pictures speak for themselves. 

Trike Builders

We're working on this thing round the clock. I spent all day Friday in the machine shop on hubs and spring linkage (it's here!). Saturday I painted the frame and Sunday I reassembled. Today I'll be in the machine shop and trying to track down the last of our hardware.
Blogging won't get it built, stay tuned.

Frameworks

It's coming alive! Ronnie McDaniel from Ronnie's Custom Auto has been working with us to fabricate the frame and its coming along great. It's all 4130 ChroMoly so it should be plenty strong as I spec'd everything on the tick side. We decided to remove a few of the gussets and tubes from teh original design since we got all the stiffness we needed already. Frame should be completed on Friday, then we'll paint it up and begin reassembly. Then we'll begin work on the a-arms and steering stem.

Flex-a-From is dragging their feet on the spring, which isn't great this late in the game. It's been on order for three weeks so we'd like to get it in hand and finalize the design for end mounts and the main rocker. In the mean time, we'll be waiting on bearings etc from Yamaha and generally sitting on our hands while time ticks away... Grumble, grumble. We really need some parts before we can move forward. Poor planning on our side weeks ago, but what can you do now? We still have four weeks, so we can do it with some good help. Stay tuned.

On Track to be On Track

It looks like we're on a 2 week update schedule, which is not so good. In fact, a lot has been happening. TreMoto LLC is a semifinalist in the Gilespie Business Plan competition, and will be presenting a 5 minute pitch Friday morning. Our lawyer is filing a petition for the LLC early this week. We will also be machining some aluminum this week. Right now, I'll explain the past two.
The Pro/E model is coming along. Ignore the abysmal colors, we're edging toward aesthetic completion, at least as far as parts count. I've been dragging my feet on hubs and front brakes, but that should be merely an afternoon's work. The Gilespie script is 95% after today's work so I can get back on the engineering side tomorrow. We've also got a laundry list of nut-and-bolt type stuff to order from Yamaha and a couple more bits arriving from eBay. The big news, for one, was Friday's teardown.
"You seek a great fortune, you three who are now in chains. You will find a fortune, though it will not be the one you seek. But first... first you must travel a long and difficult road, a road fraught with peril. Mm-hmm. You shall see thangs, wonderful to tell. You shall see a... a cow... on the roof of a cotton house, ha. And, oh, so many startlements. I cannot tell you how long this road shall be, but fear not the obstacles in your path, for fate has vouchsafed your reward. Though the road may wind, yea, your hearts grow weary, still shall ye follow them, even unto your salvation."
Also we waterjetted the bulkheads and all of our gussets from 4130 at Valley Rack in Elliott, MS. The a-arm spacers I made in shop class are not shown, nor is all the steel and Heims we got from Aircraft Spruce. Still waiting on our spring and a slot at the fab shop, but if the next four weeks go as well as last week we'll have a chance to ride this baby to our senior design presentation.

Update

Long time, no update. Mechanical engineering school will do that to you. At any rate, we've had some good luck obtaining parts. Pictured below are one of the Aprilia wheels (with tire), the Laeger ProTrax suspension, one of the Kayaba rotary dampers and a Honda hub that our custom hub may pick up some design cues from.

It may not look like a lot, but these componesnts are essential. Next week we'll be shopping for fabricators and chromoly. Bulkhead designs and material will be send to the waterjet in Grenada, A-arms will go to Ronnie's Custom Auto for lower mods (clearance for rotarydamper and mounts) top arms will be design locked and contracted for and we'll be design finalizing the spring/damper rocker based on a YZ250 axle and wheel bearings. This part will need time on a lathe and a CNC machine. If we can figure all this out this week and get some material to our fabricators, we'll be on schedule.

Flex-a-Form will get the final spring order on Monday morning so we should have that bit in a couple weeks, at which point we can build the link arms. Spring links will be short CNC'd aluminum yokes with a bearing setup to be determined. Damper linkage will come from a pair of rod (Heim) ends and and adjustable shaft.

Steering stem is going top be tricky, as the lower flag will have to be located and secured to the top shaft via a nut on a tapered shaft. We'll have upper and lower bearings, the whole thing will go together like a triple tree. It's going to be complex to build, but it should be elegant once assembled.

Hubs, however, might look bulky and I haven't had any inspiring designs so far. We'll work on that as well.

That's all for today, folks.

Goodies

One day there will be powerslides...

The first Aprillia wheel arrived yesterday, and it looks awesome. The model has been updated accordingly and includes some iteration 1 wheel hubs. We've also connected the tie rods for a working steering system. So far so good, with no interference and hopefully no binding. I've learned a lot about the steering geometry today, and we'll need to make a wheelbase change. If slow and steady wins the race, we're on track to finalize our design in the next few weeks and begin construction in earnest.