[Coley] sent in this port of jetpack for the propeller uc, but when I started poking around I discovered this sweet hybrid robot platform. A four stroke Robin/Subaru 35cc motor drives a car alternator, providing virtually unlimited (in the robot world) power on demand. Hit the video after the break for a quick R/C demo and an idea of how loud the engine is. Offhand, I recognize the lovejoy coupler that was used to connect the engine to the alternator.
By the way, this bot is featured in the latest Robot magazine, so you can get details there if you hate reading forums.
hmm… i wonder what i can do with that 4 hp engine i have…
suggestions? maybe it’ll be the next cool hack
its a 4 hp briggs and stratton upright 4 cycle lawnmower engine
I saw this in the fall issue of robot magazine. Neat little idea for powering a robot.
Pretty cool robot does solve the battery life problem even though it’s a little noisy.
I been thinking on doing a very similar setup using an 8 hp briggs and stratton .
I’ve often thought about using a gas>electric scheme like this project to power a robot. Unfortunately, they always tend to be less powerful than a direct mechanical drive and usually just as hard to to implement.
On Robot Wars they had a robot called 4×4 which used a 2-stroke petrol engine and full hydraulic drive, which makes very efficient use of engine power. Too bad it broke down in the middle of a fight, though.
Oh, and btw a Ryobi/Troy-Bilt four-stroke should work just as well, especially the new Robin-designed 29cc version.
@ greg. i would figure this is a lot easier to implement then a mechanical. You don’t need to worry about a clutch or the like. With electrical motors on the wheels you can direct drive, eliminating extra axles and gears and whatnot. Also with electrical motors you can implement electrical breaking and avoid another mechanical component. Speed control would be simpler and more pierce. With motors on either side of the vehicle you don’t need a steer wheel when you control their speeds independently. As far a power, electrical motors have more torque at lower speeds than a conventional combustion engine.
Im not trying to be a jerk just giving my opinion. Also im an electrical guy so all this stuff sounds easy to me, and you may be a mechanical guy so maybe a pure mechanical system would be simpler for you.
why isn’t a speed doubler used to get more RPMs into the alternator? Since its charging batteries and not directly responsible for the motor load, it shouldn’t suddenly increase or decrease load on the engine; it would be a pretty smooth curve that the engine could probably handle easily.
Alternators don’t really become useful until they reach a certain RPM, and they only gain efficiency until you reach the threshold of the voltage regulator.
it’s closer to ‘diesel electric’ than ‘hybrid’ – the ic engine isn’t connected to the transmission, just an alternator
‘campsite battery charger on wheels’ might be a little closer to it
I’d bet that if a very effecient gas motor, coupled with a very effecient electric generator, could be used very keenly to replace even the largest of batteries in robots… If that gas motor was made to run at peak effeciency, and there was something like a large capaicitor in the mix… The possibilities could be endless!
I wonder what kind of output that provides, compared to a Li-Ion or SLA cell of equal weight :-D
Very Efficient and Gas Motor don’t belong in the same sentence
It would require yet more heavy hardware, but would make the most sense to implement a starter. i mean, the whole idea is prolonging operational time. no sense running that engine while the robot is sitting around waiting on data. the average robot is not constantly moving. So, when the battery runs low, start up the motor, charge it pretty fast, then shut it off again.
15 minutes of battery life or 15 minutes of gasoline, is still only 15 minutes of run time! with an automatic starter and shut down, 15 minutes of gas and 15 minutes of battery is more like 25 minutes run time.
It would be really cool if he ran that off propane or some other alternative fuel.
Very nifty, though I shudder to think of the pollution your average small mower / weed eater / etc. gas engine produces…
This can allow people to make bots like in the game Bioshock! Gas-powered machine-gun turrets and helicoptors (also with machine guns of course).
how hard would it be to make this feasibly powered by propane using this info?
http://home.earthlink.net/~lenyr/pplmwr.htm
This is a very interesting project!
I built a battery-powered wheeled rov that lasted over ten hours in the field with a 25ah battery.
the addition of a system like this could make for some very very long running times, but I agree the motor should have a starter on it so the engine can be stopped and started as needed.
The machining on that base is beautiful.
The guy works for parallax too, which is a great company for microcontrollers and some nice folks too.
very very cool
Propane, a fossil fuel, why? The days of it being a lower cost alternative to gasoline for motor vehicles are over. The concept of an ICE directly driving an auto alternator is nothing new, but this implementation of is is close to art.
Yes..this is just the way that everybody want
i doubt he wanted to use propane to try and save some money on running his robot, probably because of the emissions compared to gasoline. if it ran on propane you might be able to use the thing indoors. just like warehouses usually have a propane forklift to use inside.