Future mod idea... too agressive for me! - Page 2

flatlander_14 · #16 05-26-2003, 06:15 PM

what does a buffer capacitator do? i remember hearing about someone charging some of these in their car instead of batteries. does that work too? sorry to get off topic. how expensive are these solar cells you are talking about exactly? anywhere online you can see them?

Azimov · #17 05-26-2003, 06:31 PM

Quote:

what does a buffer capacitator do? i remember hearing about someone charging some of these in their car instead of batteries. does that work too? sorry to get off topic. how expensive are these solar cells you are talking about exactly? anywhere online you can see them?

A buffer cap is a capacitor or capacitor bank with enough storage capacity to run the car for a few seconds when the solar cell output is to low to do the job. It isn't enough to run the car for an extended period, just enough to get back into full sun after sliding into a shady spot.
Yes, you can use caps instead of batteries, but they would need to be huge. For example, I had a 10F super cap once that would probably run the car for only a few seconds. It was the size of one of those little V8 juice cans. If someone told you they could run a car using caps and got an equivalent run time as compared to the stock battery, I would doubt their word. That is, unless they had a capacitor bank the size of a baby bottle strapped to the top of their car.
The cells I plan to use aren't available anywhere. A friend sent them to me as a favor. They are .5VDC @ 350Ma. They are very small and practically weightless as they were originally intended for a NASA satellite project that was scrapped. I plan to use 3-4 of these in series to do the job. I have seen similar cells online, and I don't remember where, that were almost as good, but they were around 25 dollars each. I could try to find a link, but I don't think it's worth the 75-100 bucks it would take to slap em on a Zip.

Rex · #18 05-26-2003, 07:58 PM

TaDa! It's already night here in Louisville, Ky so I'll haveta wait till tomorrow to test this out. It's the panel using the secs mentioned previously.

It might work... It might not. I know for sure that it has the umph to spin a "racing" motor, but I don't know if it has the power to run the whole Kit-&-Kaboodle.

ViperKid · #19 05-26-2003, 08:08 PM

hey rex nice job....by the way i know some peaple in Louisville!

Azimov · #20 05-26-2003, 09:05 PM

Looks good! I still have my doubts, but let us know how it does.

flatlander_14 · #21 05-26-2003, 09:15 PM

thanks for the clarification azimov. the guy never said anything about how long it ran. he just said that his friend tried it. i dont know. lol. rex, i expect a post in this thread tomorrow when i come back from school

ps - azimov, that clown avatar of yours creeps me out. hes too happy.

Azimov · #22 05-27-2003, 05:10 AM

And, TA-DA right back at ya!

Here's my candidate. And...Dum Dee Dum Dum... It works! I tested it 12 inches under a 100 watt halogen lamp and it works very well. I'll report again when I test it in sunlight. This model features paper clip bumpers to protect the very fragile solar cells, a spring antenna, and a sporty little rear spoiler. The cells produce 2VDC @ 350 mA. The car has the original PCB and is using the red turbo motor with red gears. I may change the motor and gearing after further testing.

Azimov · #23 05-27-2003, 05:11 AM

Another

Azimov · #24 05-27-2003, 05:13 AM

Last one. Sorry for the crappy PICs. Proping this thing up on my scanner is a pain.

Azimov · #25 05-27-2003, 05:21 AM

BTW, the bumpers are attached to the chassis and not the solar cells. The car's battery was removed and the solar cell leads were soldered to the battery contacts. The solar array consists of 4 individual panels with a rating of .5VDC @ 350mA connected in series. Even with all this stuff on the car, it weighs less than it did with a stock Zip body. I held the car under the lamp to get the right distance so I haven't run the car on the ground yet. The steering was responsive and the motor screamed!

Rex · #26 05-27-2003, 09:55 AM

I tested mine this morning but got no responce. I'll take the cells outta the existing solar case and series it with a second after my next paycheck. I tested it at 1.77 V @ 100mAh. It'll spin the motor like crazy when I hold it directly up to the leads, but I guess the PCB pulls too much for the panel to handle.

Azimov · #27 05-27-2003, 03:31 PM

I took my solar Zip out to the concrete slab in front of my garage and it worked beautifully. The car ran fast and steered very well. But, it would come to a halt if the slightest cloud came over. I noticed that the steering was still responsive even when the motor wouldn't move the car in these conditions. So, I took it back in the house and switched the red gears for blue and switched the red turbo motor for the blue control motor. Took it back to the slab and it works much better. The car performs in full sun and overcast conditions. If the clouds get to dense, it will still lose power, but works very well now. The spring antenna allowed me to sit some distance from the car as I steered it around dead leaves and such on the slab. Since I'm using the original PCB, the car slows considerably in heavily overcast conditions when I hit the steering control. I believe this was fixed in later PCBs. But, in full sun, and slightly cloudy conditions, the car performs as if it had a dual cell mod. Now, if I can slap some solar cells on the controller, I could sit and fry in the hot Georgia sun all day without worrying about batteries.

Rex, I would suggest trying the blue motor and gears. And, when you get that second solar cell, try hooking it in parallel instead of series. This will give you 1.77VDC @ 200mA. This may work for you. But, from what I've seen my car do, I'd almost bet you need three hooked in parallel to get you up to 1.77VDC @ 300mA. I just rechecked the specs on these NASA cells and they are rated at .5396VDC @ 324.2mA. @ 12.5% Eff. So, 4 hooked in series is giving me 2.16VDC @ 324.2mA. That suggests to me that you will need at least three of the cells you are using hooked in parallel to get you up to the required power level.

Rex · #28 05-27-2003, 04:09 PM

I found a panel on sundancesolar like this:
.5V @ 200mAh

They're small enough for 2 to fit in the same space that the current one takes up now.

Give me your thoughts Azimov?

#29 05-27-2003, 04:41 PM

Quote:

Originally posted by Azimov
Another

Wow, that is just about what I originally pictured in my head!
Incredible!

You seem to be worthy of the name, even if the spelling is a little different!

If it works with the chassis, so much the better!
You did an absolutely beautiful job! (Love the spoiler!)

Thank you for saving me the trouble of building this. Now I can live vicariously through you!

Fourteen thumbs up!

#30 05-27-2003, 04:59 PM

Your solar project deserves to be in the BitScience section I think.
Simple, elegant and well presented, your project has my nomination.

On the topic of aggressive mods...

This is also another reason why I'd like to start using the receiver boards from Zips (Bits are better, smaller size) and mod them into some "non-standard" RC applications.
The board can be made to fire four relays with the addition of a few diodes, or use transistors if you want to keep it solid state and ultra low power.
What you end up with is a very tiny RC controller that could be made to control something quite large by comparison.

And extending the range is an easy matter from both ends with longer antennas and more batts in the transmitter.

Personally, I'm thinking a small outdoor ROV, a "Micro-Probe" if you will.