Alternative Power Sources?
 

Has anyone experimented with alternative power sources for your robot? Such as hydrogen/direct methanol fuel cells, solar cells, lemons, etc?

Personally I'd like to see a lemon powered robot.

Re: Alternative Power Sources?
 

Not really, but we have experimented with additional power sources. For this one project we had to put 99 Amp-hours of SLA batteries on there. Needless to say, it was quite a heavy robot.

A lemon powered robot would be cool though, you think there's enough juice (literally) to do it? :D

In chem lab, we made some small voltaic cells and got a whole volt out of a couple of them. While the voltage was fairly impressive, I'm sure they couldn't provide much current.

Re: Alternative Power Sources?
 

I'd like to see a small bio-desiel generator on a FIRST 'bot.

Bot acting sluggish? Go fill up at your local McDonald's!

-Andy A.

Re: Alternative Power Sources?
 

I bet someone could get a small gas engine and hook it up to an alternator. It might not be as useful as a hybrid electric vehicle... but it would be interesting to do if you had the time/energy/parts. Just remember to think about safety, energy, efficiency, etc... if you try this.

Re: Alternative Power Sources?
 

you could use a model gas engine they use on the gas powered remote control cars to power an alternater. im experimenting with this to provide power to a personal robot ive been planning to build for a while now. :D im also working on using solar cells to power capacitors on a helium blimp robot im starting to build.

Re: Alternative Power Sources?
 

Interesting... I'm doing the same thing. But I'm doing it on a really small scale. Using a Cox 0.049 engine and a small electric motor. All I'm trying to do is power a little "car" platform, and use it as a fun little demo.

Darn yardwork and house rennovations keep getting in the way however.

Re: Alternative Power Sources?
 

My pet gerbil got very tired of powering the robot. I assume that's why FIRST specifically bans gerbils as an alternate power source.

Re: Alternative Power Sources?
 

Doing some research for a project, I came accross Saphion U-Charge batteries (from Valence). In 15 lb, they pack 45 Ampere - hours at 12 volts, and have a lifetime of 2000 charges.

A lighter battery is the Ultralife UBI-2590 UBI-2590 . It weights about 3 lb and has a capacity of 12 Ah at 14.4 volts OR 6 Ah at 28.8 volts. FOUR of them would fit within the battery weight of the robot, and would provide 24 Ah at 28.8 volts. That voltage can produce over two horsepower from a drill motor. I don't know about CIM's but it says "12 V DC", so it might not be a good idea to try it. Batteries have a future, just not lead acid ones.

Re: Alternative Power Sources?
 

One should read further and check out the safety warning at http://www.ultralifebatteries.com/wh...recautions.pdf

You will note in this document that these batteries should never be subjected to discharge above the rated current, dropping or sudden or repitive shocks. The result may be heat, explosion, or fire.
It is also interesting to look closely at the discharge curves compared to SLA. For one, check that the batteries being compared are the same size but not the same current rating so the curves are slewed to make the Li battery look way better. Note also the discharge for the Li batteries runs out to a point and then takes a nose dive while the SLA battery slowly drops the terminal voltage. The final thing to note is the graph only shows performance down to 10 volts not the eight that we are more interested in. Using this type of battery in one of our matches would produce a dead robot when the battery is discharged instead of a marginally operational robot. A check of the original spec sheet will also inform you of the need for special charging and special protection circuitry as part of the battery to protect the user from exceding the safe discharge ratings.
I like the use of solar chargers, or human powered chargers. A robot that was using one of those methods should be given a couple of extra points in a match where they are using a battery charged by one of these methods.

Re: Alternative Power Sources?
 

You will definitely need a huge power source to run this baby! :eek: I want this! :eek: Good luck trying to run that off a lemon!

Re: Alternative Power Sources?
 

When I think about it... alot (not all of course) of our typical energy sources can be traced back to the Sun.

Robot Battery is powered from the wall
The wall is powered from the power plant
The power plant runs on Coal, Oil, Natural Gas, Wind power, Solar Power, Hydroelectric, etc... (I left out nuclear, tidal and geothermal on purpose) All of which can be traced back to the Sun.

Coal-Organic-Plant material-Sun to grow the plant/animal
Oil-Organic-plant material-sun to grow the plant/animal
Natural gas-organic-plant material-sun to grow the plant/animal
Wind-solar energy moving the air
Solar-It's the sun, dude
Hydroelectric-Evaporation and precipitation raising water's potential energy

Here's one to think about. Full Cells - where are we going to get the Hydrogen? It doesn't just come when we call it. (Or does it? Hydro... Hyddie... are you there?) :)

Re: Alternative Power Sources?
 

We could use geothermal, which is independent of the sun, to get hydrogen.

Or cold water power. Now thats cool, although it is somewhat solar reliant. It is virtually free though.

-Andy A.

Re: Alternative Power Sources?
 

Fuel cells are prohibitively expensive at the moment. I read about them in Servo Magazine and the price was really expensive that I could buy a complete robot for the same price as the fuel cell. Solar cells are useful in smaller robots and can directly power a BEAM robot but their ability to work is dependent on the sun and of course the cost is still expensive for larger solar cells. Research is being done with organic materials in order to create new solar cells. Last I knew it was spinach and blackberry (sorry I forgot which berry) that is being used. As for other power sources. I know of one robot whose sole purpose is to eat slugs and use them as a power source. As for batteries you have nickel cadmium, nickel metal hydride,sealed lead acid and lithium ion. These are the only three that I can think that are useful for any type of robotics work. Just match the battery to the job you want it to do.Please someone might want to elaborate because I'm not 100% sure of this but make sure you filter out the output of the alternator or else spikes create d in the alternator might blow any electronics you have. As for powering a blimp using solar cells and capacitors, I would recommend using a BEAM engine particularly the one I'm linking to. It uses a few capacitors and a few other components to power a motor.BEAM

Re: Alternative Power Sources?
 

anyone know where i can get a very small alternator.

Re: Alternative Power Sources?
 

Another thing I have looked at from Valance is their ncharge power packs for laptops/notebooks. You can run upto 10 hours with one of them. BUT note the price of these things!

Back to the original question I am actually working on 1) a hybrid car which will run off batteries charged from an engine or Hydrogen Fuel cell. 2) powering part/all of my house off a Hydrogen fuel cell. 3) Building a "bomb squad" robot powered from solar panels and hydrogen fuel cells.

I contacted a company in Canada I believe and could get a 1200 watt 12 volt ( so ~100 amp) Hydrogen fuel cell for about $5000. Not too bad considering how much energy it could save me.

As for power during competitions I am building a portable power pack with 3 inverters and about 200 amp worth of SLA.

-Mike