August 2010 firstname.lastname@example.org
The experimental aim here was to build smallest workable 2 wheel transporter and put it into a small rucksack. Big problem with the Segway, and my earlier machines, is you cannot carry them easily if at all.
This concept gives you a certain versatility:
a) Can pull it along on the small blue wheels like an airport rucksack with the extending handle.
b) Can wear it like a rucksack.
c) Over half the internal volume is still free for your stuff.
d) Can ride on it as a self-balancing scooter facing forward with ones foot each side on the footrests. Left hand holds extended handle, right hand holds Wii Nunchuck with thumb joystick
e) Footrests could fold up each side potentially.
f) You do not stand high in the air on top of it - you are at same level as everyone else.
g) Not suitable for rough surfaces. I envisage this as an occasional use device - something you might take to a showground or exhibition in a large hall perhaps, or dare I say an airport, to pootle around on.
The hand controller (hacked from a Wii wired Nunchuck) uses a front button as a kill switch to the motors if not pressed, joystick forward/back controls the fine balance point of the scooter while left/right gives you steering.
Straight line stability is given despite wheels being fairly close together, by a second gyro that resists sudden turning forces as in my 2 wheel skateboard.
Arduino microcontroller and Sabertooth motor driver used. Two 250 Watt motors. Wheels are from rear of a "Rockit" powered skateboard.
Small blue wheels required when you get onto it (tilted forward with blue wheels on ground) else it would tip over to one side as you stepped onto it.
These are airborne when scooter is running.
Turn it on, stand on footrests while tipped forwards on ground, press and hold kill switch on hand controller, tilt it back to the level position whereupon it will automatically enter "self balancing" mode and off you go!
All electronics one one single slab of polycarbonate. Arduino to left, sabertooth to right. Easy to take out and replace during development. Screw connections for battery/motor wires.
Internal alloy frame. Lagre comfortable straps from a larger rucksack are fixed to this inner frame - tricky to do.
Rucksack now fitted. Straps emerge through slots in this smaller rucksack covering. Run soldering iron against cut nylon edges and they won't ever fray.
Tilted forward resting on small blue front wheels ready for me to step onto it.
Q: Why put it here and not patent it?
A: Would be very expensive to make: Chassis, motors and chains all have to be in correct alignment and tension, inner frame, straps attached to inner frame, specially made outer rucksack covering and so on. Has taken me a week of hard work and I have built quite a few similar devices before so am much quicker than I used to be.
Could only probably be buit to order as one-offs, supply your own outer case!
A: Coming soon when it stops raining.
Q: What next?
A: I may take it to the Lotus components show October 2010 to test it out in the halls of the 3 Counties Showground, Malvern, UK.
Looks like this concept might just work!
2 lead-acid batteries used here (I already had them). Lithium would be much flatter. Even with lead-acids you can see there will still be over half internal volume of the rucksack free to use for your own gear.