Ive made another video about my crab buggy design to follow up on comments I recieved about the original design, and also show two options, one with and one without a rear shock. Here is the link to that video:

http://www.youtube.com/watch?v=1oWNr2oFANk&feature=youtu...

And here is the link to the previous thread. I had to make another to do the poll unfortunately.

http://www.powerkiteforum.com/viewthread.php?tid=26629

So the question is... should the buggy get a shock? What do you think... Yes or no?

Thanks!

I vote yes because the passenger should be in confort.

You have too much from the waist up. You would never be able to do an upwind turn with that rig. And is that a brake? Brakes are not allowed on kitebuggies. If you need a brake ,you don't know how to fly or buggy. To answer your Q. No, shocks on buggies tend to make the buggy lean to the kite.

Weldngod, what about a sway bar?

Are we voting on a shock on your crab buggy or a standard style buggy ?

Weldngod,
I don't think it's a brake. It's hand controls. He's in a wheel chair.

My first thoughts are no shock. I like turbulence in airplanes, but what do I know?

I'd guess that a shock would add a bit of cushy comfort to the ride, without much additional engineering or build time. As far as the leaning issue , no doubt the spring is pushing you over in the direction of the kite and the weight of the axel arms and wheel won't act as a counter weight until lifted off the ground. So even though there is no shock being compressed on the downwind side like on a regular bug , losing that counterweight effect will cause it to lean or tip easier and/or more quickly. Cushy is nice though , maybe you could just run a big soft tire back there.

I thought Peter Lynn made a buggy with shocks on the rear. I have a picture and thought I might want to try a set-up like that.

On another forum I also read that the shocks wasted forward momentum because of energy transfer both up and down and left to right. Downwind side would moosh down and the other side would lift once the travel fully extended down.

I penciled a few drawings with rear shocks but they were coil overs that were adjustable. The adjustment, I thought, was necessary for wind conditions. The lean over factor was a concern. So then I thought about air bags in cans. The up and down travel would be contained in 2 sliding tubes that had just enough space between to allow the bag to move up and down but not enough to lean. And again the up and down travel would have to be adjustable for wind conditions. Sand, water, dirt, between the tubes and air bags getting pinched may also be a concern.

Maybe a shock suspended seat might work better that could be adjusted on the fly for up and down wind runs.

Just some ideas I had about shocks.

Also, didn't someone design a front fork with suspension?

Time for you engineers on the forum to put in your 2 cents worth now. Help a brother!

Quote:

Brakes are not allowed on kitebuggies. If you need a brake ,you don't know how to fly or buggy

LOL! Watch out for the Buggy Police!

While the two can't compare directly, the Carbon Buggy originally had shocks on it and after a bit of testing it was quickly realized that they hindered more than helped. If you're going to run bigfoot tyres, shocks shouldn't be necessary unless you're on really rough terrain. And even in my bumpy paddocks at home, I find the bigfoots absorb a lot of the bumps.

As for doing upwind turns.....you'd end up the wrong way round! Unless you do a 360.......never seen that done in a crab...

Cheesey has a Peter Lynn Monster buggy with shocks on back. It will be at WBB. For some reason PL didn't stick with shocks ?

Jon and most of the Sunset crew run a shock type system on the front wheel of their Libres. I am not certain if it is an aftermarket item or if they are special built ? I do know that everybody that has gotten one that I know kept it. So .....

Wait a sec. I'm gonna be a passenger in this thing!

I kinda want to change my vote to "maybe"!

MyAikenCheeks has a great idea to shock the seats! I vote for that now.

I've been looking at mini ATV's. They've got an upper and lower "A" frame that houses a shock and a ball joint axle.
Weld the ball joint so as not to turn. Machine a 20mm (what ever) axle stub. Mount the "A" arms on a plate, weld a pivot for the shock on the plate, and attach them to the rear buggy axle with the axle bolt.

My thinking here is that a wide enough rear axle will keep you planted and give you a good ride.
Will I get a ticket from the buggy police for being over width?

Adjusting the pressure in your Big Feets is a good solution. I rode a ridged Harley, '51 FL, for 27 years and I always, had too, adjust the pressure to save my back. Well, almost. Only my chiropractor knows if it worked, or not.

In a crab buggy, the shock on the rear wheel would not be subject to forces to make the buggy lean. Also in a crab buggy, you wouldn't have any need to do an upwind turn, since you are always facing the kite. Every turn would be a stop, then head off again in the other direction.

Steve Bateman has one of those buggies with shocks and I dare anyone to try and get away from him. The shocks don't seem to hamper him at all.

I've considered brakes for my buggy because I sometimes find myself unable to stop due to flying overpowered to begin with and have the wind increase just when I'm running out of room. There isn't much else to do if you are sliding sideways trying to turn the buggy upwind and you get more power from the kite when it's low and more lift if it's high. I'd fly a size larger kite all the time if I had brakes. I'll agree with the no brakes comment if you're flying on a beach.

I think the shock is a no go, at least on version 1. The main reasons being keeping the cost down, keeping it simple, and also the pitching forward affect or the buggy tending to lean towards the kite being undesirable.

Djinnzfree: Absolutely. We will make sure and have a really good cushion in the seat and good padding. We'll just have to steer around the big rocks.

weldngod: Did you watch the video? Crab buggies are different than regular buggies.

Snowspider: yes to all that. Thanks for the input.

Myaikencheeks: I think the suspended seat idea is a really good one. It would give the passenger some cushion without having that tipping towards the kite effect. Also I'm not quite following you in the second post.. Are you talking about doing the suspension with two A arms instead of one swingarm like in a car so that the wheel stays perpendicular to the ground?

John: I've seen 360s in a crab. They were much lighter than this thing though and obviously didn't have a rollbar. I think they are possible and attempts will be made.

Beamerbob: Thanks for the input. Its not a brake its hand controls for steering.

I will say this poll went in a totally different way than I thought it would. Glad I asked.

Yeah, brakes shouldn't be necessary on a beach since you can so easily slide to a stop just as quickly as brakes would be able to stop you. On grass or other super grippy surface, brakes might not be such a bad idea. I actually prefer not to be on grass for that reason... My wheels do not slide on grass, so my kites just try to rip me up and out when I turn upwind on grass. But for the record, I prefer to fly well powered/overpowered in my experiences so far. It just allows me to travel almost any direction especially with the Toxic. I swear it feels like I can go 45 degrees upwind on that thing. If you are using a good low lift kite, you shouldn't get loft as long as you don't do anything silly like send it while at speed. To manage my speed, I just put the bug sideways and keep the kite high until I feel I slowed enough to whip it around a turn.

How bout putting a shock on the seat cradle only..?

Hello, I'm from the NKBRA, aka Nick bra, aka National Kite Buggy Regulatory Agency. The BHO administration has footage of 3 wheel buggy type vehicles things traveling at high rates of speed in National Parks, dry lake beds, public beaches and soccer fields WITHOUT brakes and this has to stop, ASAP!

Altho we only know how to regulate, and we believe that all such 3 wheel buggy things require brakes from this point forward. We have no idea as how to put brakes on a buggy thing, we just require them.

Please submit idea's to Nick bra or this forum so we can forward them the the National Safety Transportation Bureau for consideration and testing.

Until further notice, all kite buggy thingies are to be parked until a satisfactory brake design has been approved.

Thanks for your understanding, and submissions.
The Kite Buggy Police.

Wow, I love this project. If I had a larger kiting budget I too would pursue one of these. Please keep us in the loop so we can live vicariously through your work.

As to your question, the best shock systems I have seen are elastomer based. The goal is not to provide wheel travel in the face of troughs and bumps but to dampen vibration caused by washboard and other irregular surfaces. This improves wheel contact which minimizes side slip and drag while helping you hold that ever-important upwind line. However you do this, the wheel must be held in plane as it travels. You cannot let the left and right sides of the wheel fork move independently or the wheel will just lean towards the kite.

As to the roll bar, it makes me nervous. A common OBE for conventional trike buggies is to eject forward during a massive deceleration. Imagine what would happen if you hit a two foot deep pot hole full of water at 20 mph or more.** The rider typically pivots on the foot pegs as he/she is ejected. Looking at your latest demo video the roll bar seems to be in the path of the pilot's head during an ejection. That could could be bad.

Perhaps you prevent ejection with the 4 point harness. Whats's more, between the buggy weight and rider weight it might be very hard to flip this buggy. I hesitate to say any bug is unflippable, but I have seen some that came close. Bobby loaned Popeye's Hero Buggy at NABX and have to say I did not worry as the buggy started to slide at 40+ mph. I think the only thing that could flip such a buggy is a pothole or a trough, but they do exist and they will occasionally make a fool of you.

So you have to ask yourself which you prefer more: ejection and separation from the buggy with a kite that is still flying or being trapped inside an inverted buggy with a kite that is likely still flying. These are difficult choices. I'm in no position to comment on how a disability might weight that decision.

I'm looking forward to the next iteration. Thanks so much for sharing.

Philip

**Yes, been there, done that.

Hi,

It really depends on the type of terrain you are goint to roll on. If it is smoth, The shock is not very helpfull. If your terrain is quite irregular, it is a blessing.
On the crab it is more or less the same thing. I would leave the shock desing in. I would test with the sock and with a fixed bar. You could allways put in the sock absorber if you like.
The steering, is adjusted with with the holes in the streering system as servo throw is adjusted in a RC planes.
Olivier Suire, likes a whole bunch of streering (tested his crab last summer, wow it really turned ), where I prefere less. It really is a matter of testing. When I want to go fast, I will leave very little strearing throw wheras I want to skid, I will put more.

I think the shock behind the pilot on a crab is a great idea. I would make it an adjustable shock that would go from no movement to so soft a fly would complain it is to stiff.
I am glad the rear axle shocks have gone byby.
Libre has designed 4 different sized front fork suspensions systems. Untill you try one, you have NO idea of the comfort and the need to have one on your buggy.
As for the brake idea, my mind is made up. If you are running out of room and need one, why are you doing what you are doing at that spot? Doesnt sound like you have any control. Please post all of the videos from all tests and trial runs:evil: Proof is by far better than talk talk talk about a new idea.

Sorry about being kinda off topic, but what CAD program did you use for that?

Can't really watch videos

Thanks

love your design and love the fact that it has a roll bar protecting people,i really hope this hits off for you as you have considered people and people with disabilities ,keep up the great work

The crab is geared toward comfort so I would go with the shock. the front tires are your traction and the back is your support so I don't think the shock will affect the traction at all. also sounds like you are designing this for the lake bed? I would use disk instead of Big foots. also appears to have pos camber on the front? nice work BTW