Team 871 - Homebrew Segway

[GregTheGreat]

For those of you that have built you're own...

What type of motors did you use?

Thanks.

[D.Fahringer]

The grey tube that twists is bored to fit nice on the handlebar tube so it turns easily but no sloppy fit. (for the sake of the potentiometer relationship)


There was plenty of talk about a return system but if you think about the potentiometer and how it can slip a little now and then the return position may be off a little. If you have a more positive grasp on the potentiometer you could do the self return thing.

Personally I am controlling the rate of throttle advance and shutdown so completely as I balance I would prefer not to feel any resistance. I could get used to it I'll bet! And it would have to be a good thing for a new rider. It can get confusing when the machine is set to moving forward or backward in a turn and you have to figure out which way to turn the grips to get it to stop.

I marked the pot wheels to indicate the center position and that
is where you set it before turning the machine on.

You could use a zip tie as a resetable visual check temporarily I guess.

[Willum]

Just checking, but that's not gyro driven correct?

[D.Fahringer]

Yep no gyro installed yet, see?

On the subject of drill motors, there is considerable slop in the drill transmission that will be hard to deal with on a two wheeled "segway" This is a problem because the reaction time
to correct imbalance before things get out of hand is small.

It is a good powerful motor though worthy of a custom transmission but you have enough work ahead of you.

The most popular choice seems to be the Fisher Price.
I thought it had a lot of slop too but that one I based my opinion on had been modified...they are acually very good when new!

Moe will have one! (Moe Go)

[GregTheGreat]

That helps a lot, very good design.

Where can I purchase the Fisher Price motors?

Thanks.

[Matt Krass]

You guys are scaring me, my design uses the 2003 bosch and tranny as drive. Are you sure it isn't good enough? If it isn't it means a big redesign of the base....Just how much slop are we talking?

[Victim of Fate]

Ive been seeing quite a few homebrewed segways(indeed, I plan on building my own). And was thinking of maybe "segway races" next year at nationals, would be quite a sight.(hehe)

[Willum]

So. Getting back on track.

http://frohawk.no-ip.org/

check here now and then for updates, new pictures, etc.

Has anybody given much thought to the gyro programming process or am i alone on this?

[sanddrag]

Do not go to the above link unless you like clicking your mouse or pressing enter about 100 times.

The messages were kind of funny though.

<edit>Go to this link instead http://frohawk.no-ip.com:8181/craigway.htm </edit>

[D.Fahringer]

Quote: "You guys are scaring me, my design uses the 2003 bosch and tranny as drive. Are you sure it isn't good enough? If it isn't it means a big redesign of the base....Just how much slop are we talking?"


It's a pretty big deal because there is very little play in a good window motor but I had a gear set that was sloppy (about an inch of free movement as measured at the floor) and it was a lot harder to keep balance and look smooth. That is because by the time you make a correction it may have to take all the slack out of the drive train first and that means more time before the correction is actually stopping the fallover. Also... the faster your machine is the more important it is not to have slop because tall gearing amplifies the problem, the wheels will travel further freely
with that slop or backlash in the transmission.

If I remember right, the 2003 drill had about 20 or 30 degrees of rotational free play? Check it out maybe yours are better.

All this means less if you are always on the go, and most noticeable when stopped and balancing.

Dave

[Willum]

oh yeah .... sorry about that, i'll get that javascript out of there asap.

edit... all better.

[Willum]

I went into school today and took a lot of pics of the underbelly of the scooter. You can see how simple the layout really is.

http://frohawk.no-ip.com:8181/upclose.htm

Check it out ^^^

If you haven't done so already take a peek at the videos on the first page of this thread.

[D.Fahringer]

Power Wheels maker Fisher Price is now owned by Mattel and they have a service number ......800-348-0751

Couldn't get a look at the motors themselves in their pdf manuals
they should be in there but I couldn't find them!

[Matt Krass]

Anybody have an ideas on how to lock down the drill motors and eliminate the slop? or make it less severe to a point where it can function? I don't really want to change the design to use the FP motors, I have doubts they can handle a large load swiftly.

[D.Fahringer]

How bad is the backlash slop on your drill motors?
Roughly in degrees. Does it have the same amount in high or low?

I am no authority on FIRST motors by any stretch but.....

Team "Segway" Motor choice Pros and cons as I see them.

Fisher Price: pros: Comes in left and right hand so motor speed is matched, good or reasonable power, cons: a little loud, motor can sticks out in the way,

Drill motor: pros: excellent power, durable, has cooling fan and vents, cons: motor assembly is long and will get in the way of either ground clearance or rider platform minimum height. lots of backlash in drive train,

Window motor (1998-2001) pros: slim and allows for the lowest center of gravity mounting of all motors, quiet operation, low power consumption, left and right version matched motor speed, cons: not powerful enough! a little delicate for abusive learners.

Vandoor motor pros: slim and mounts pretty low, should have good power, easy to mount, cons: only one hand available may veer at top speed, has plastic worm gear inside possibly delicate,

Chiaphua: pros: Big motor, motor itself is quiet, easy to mount,
cons: must have custom transmission, probably will get in the way unless a worm drive is used.


Seat motor: Forget about it!