Hi,
I would like to make a vehicle that can both fly and be drivable on the ground reasonably well like a car.
I thought about a quadcopter with a set of three wheels: two motorized wheels and another non motorized one. I could use a mixing of the two wheels to go back/forth and turn as well. I don't want to be nervous and go fast on the ground.
What about motorized wheels (small wheels with built-in small direct drive motor) ? We can see that on electric bicycles but I can't find anything for RC. A small motor/gearbox/wheel compact set would be acceptable but I tend to prefer non mechanical parts on this, that's why I have a preference for a direct drive.
Any ideas anyone ?

This is the best I can think of for something that can go on the ground, as well as the air (and even water)

BIG RC Hydro! (4 min 18 sec)

I think if you have something that had motorized wheels, and also had to fly, it might be quite heavy.

Thanks for the reply ! This model looks fun indeed.
However, I'm really looking to add very basic rolling capability on a flat ground to a multicopter. Highly reducted gearbox with motor and/or very small wheel might do the trick without adding too much weight, this could also be easily removable... I might anyways want to build a dedicated small ground vehicle using such motors and some IMU (but without the take off weight problem).
I'll keep searching.

How about just some large diameter outrunners with tires glued to them?

^^ That would work, but you'll need REALLY low kv motors to make that work.

Not really all that low. A 24mm 1000Kv outrunner at 12V is only 12,000 RPM, giving you about 36 MPH wheel speed. Mini-Z tires and the like will handle that speed fine.

Thanks !
The thing is that I don't want to add too much weight as this will be mainly a flying machine. I just want basic low speed taxiing on the ground, that's why a small light reducted motor with a small wheel would be good.
I'll keep searching...

Originally Posted by gsa

Thanks !
The thing is that I don't want to add too much weight as this will be mainly a flying machine. I just want basic low speed taxiing on the ground, that's why a small light reducted motor with a small wheel would be good.
I'll keep searching...

Why don´t you try a wheel to servo setup like robot guys do?

You just need to get a pair or free rotation servos (no inner potentiometer so output shaft can rotate more than 360º...) and a pair of wheels attached to their output arms.

Each servo can be connected to a Rx channel so any mixing is directly given by the Tx.

Each servo feature its own motor, esc, gearbox at a very low weight. But be sure to get dual bearing servos and metal gears...

Originally Posted by trf_414_m2

Why don´t you try a wheel to servo setup like robot guys do?

You just need to get a pair or free rotation servos (no inner potentiometer so output shaft can rotate more than 360º...) and a pair of wheels attached to their output arms.

Each servo can be connected to a Rx channel so any mixing is directly given by the Tx.

Each servo feature its own motor, esc, gearbox at a very low weight. But be sure to get dual bearing servos and metal gears...

Thaaaank Yooouuuu !
I hadn't heard about this kind of servo mod and with your help, I found dozens of interesting references. There are even pre-modified systems for sale but with big servos, I'll go with modifying a micro servo.
This is *THE* reply I was expecting. I consider this question closed.
Thanks again !