Idea for Acceleration

[Steve]

OK, calling all electrical engineering nerds! The idea is based on a camera flash. Cameras charge up a what I think is a capacitor with some insane volts, then unleash it all at once. Well, I want something like that in my SE. A capacitor that stores say 4volts, then unloads it upon accelleration. So basically, whenever the car is completely idle (like at the start, or rolling into a corner) it charges this capacitor, and when the gas is hit again, it dumps whatever charge it has. It doesn't need to be much, just a little "boost". It would be most effective off the line, but it would help a little on tight tracks also.

any thoughts guys?

[Jtskty]

That could work, maybe. I think you would have to wire the capacitator so it skips the board because of the components not being able to handle that voltage. Great idea though.

[Steve]

Well I gave it some more thought (bump), and the biggest capacitor I was able to find was 160uF. I juiced it up, connected it to the motor and it turned it just a tiny tiny bit. So my next mission is to find a capacitor with a whole lots more storage "capacity". I'm thinking around 800uF or 1000uF would do the trick, the only problem then becomes size. I don't know if I can find the right capacity in a small enough package.

This also got me thinking about dragster Zips. Using the stock 1.5 volts or whatever they are, ramped up to 3x that and pumped directly to the motor would give a massive launch off the line. It would essentially use the same setup as a camera, with the charging circuitry that ramps 1.5 volts to over 400volts. That's a bit much, but the idea is still the same, and if you could keep it small enough it would rock! For a brief second, you'd have the mass voltage of a quad cell or higher, without all the weight associated with the extra batteries. I'm thinking wheel stands galore!

[Racer9]

actually there is some 1000uf that are half inch long and 1/4 in dia.

[Steve]

well I found a 1200uF and it gives the motor a good shot of juice, and I could cram it in the hatch of the Toyota...I just don't have any idea how to charge it when off the gas, and add it's stored voltage when on the gas. HELP!

Your stupid you would need a whole other radio channel to do this.

BC EDIT: Please do not insult other members.

[frizzen]

First off, the PCB already has a Cap that does just that installed.

Capacatance in paralell is addative.

SO If you tag another Cap in on the board next to a stock one. (2 stock caps now in parallel) You'll get the power bump and it *probably* won't torch components on the board. It would only give you like 200 uf, which you could do with a single better cap. But, if you were to take some of the higher capacity ones....

OR you should be able to rig up a circuit where you use a transistor and like a button cell battery like an amplifier. That way stock pcb should provide the signals to do it all. But instead it charges the new caps and thus motor.

if anybody has the schematic for the ZZ pcb, I could try to figure out the circuit.

On my micro RS4 I have something similar to this coming from the battery and into the ESC. Basically it's a large capacitor that gives the micro a bit of a punch after coming out of a turn when you first punch the throttle. I'm not sure how you would wire this up on something like a Zip Zap because you cannot isolate where the "speed controller" is on the board. The cap needs to be by the input voltage, not the output where it goes to the motor. Frizzen sounds like he would attach a cap to a similar type thing on the board? Is that right frizzen? Oh and it really does make a difference on the lil micro, it just totally burns out when you punch the throttle!

[Jtskty]

Now that I think about it, wouldn't it be better to let the boost come after say, 1 second so that it doesn't spin out so much when you first hit the gas.

[frizzen]

Yeah, depending on what the board could handle, I would either bump up the capacatance on the board; or build up something like a 'boost box' to wire in between the PCB and Motor.

The problem is that either way, you'll be adding weight, so even though you'll have more punch for hole-shots and out of the corners; your top speed will be a little less. So you'll probably want to combine a couple more mods into the car.

With the ZZ SE you have a *sorta* propo throttle, right? So you should be able to rig this thing up so it only dumps the caps when you hit the full throttle setting. Instead of a timer-circuit to slow it down, it's up to you. Roll onto the throttle slowly, you get a clean launch. Jab the throttle, and you get burnouts. Smoothly roll onto it all the way, and you get a clean launch and when you hit the full throttle point, it sorta acts like a nitrous shot.

I don't have an SE yet to try to figure the stuff out on, so without a pcb diagram, I'm not really helpful.

[cyborgzero]

It would actually be best to use a capacitive ladder and you could get about as much voltage as you want.

I have built all sorts of shockers/EMF/ESD discharge units that work off of this theory.

You take 2.4 volts or 1.2 or whatever, pulse feed it into a cap ladder whereby the 2.4 volts or whatever now becomes the ground of the next cap and you literally ladder up the voltage in steps with each rung being another 2.4 or 1.2 volts added..

BUT, better yet is to simply buy a DC/DC converter chip that ramps up 1.2v to 10-12v using a charge pump configuration.

Then, you have it so that as long as the cap is higher voltage than the rail voltage it will allow a one way discharge into the motor.

Better yet, run the DC/DC converter to the entire H-bridge of the motor... After you do the FET mod the H-bridge will handle up to 20V.

That way then the H-bridge consistently is fed 10V from the dc/dc converter.

Problem is that motors don't last too long at high voltages..

Rob

[charliebrown]

Originally posted by cyborgzero
It would actually be best to use a capacitive ladder and you could get about as much voltage as you want.

I have built all sorts of shockers/EMF/ESD discharge units that work off of this theory.

You take 2.4 volts or 1.2 or whatever, pulse feed it into a cap ladder whereby the 2.4 volts or whatever now becomes the ground of the next cap and you literally ladder up the voltage in steps with each rung being another 2.4 or 1.2 volts added..

BUT, better yet is to simply buy a DC/DC converter chip that ramps up 1.2v to 10-12v using a charge pump configuration.

Then, you have it so that as long as the cap is higher voltage than the rail voltage it will allow a one way discharge into the motor.

Better yet, run the DC/DC converter to the entire H-bridge of the motor... After you do the FET mod the H-bridge will handle up to 20V.

That way then the H-bridge consistently is fed 10V from the dc/dc converter.

Problem is that motors don't last too long at high voltages..

Rob

If the motors won't last too long with that current, imagine what will happen to the PCB

Chuckster...

[skitle]

i noticed if you use the blue gears and the purple moter it has better acceleration. go ahed and try it your self i must of benn trippen or something.

[cyborgzero]

Originally posted by charliebrown
If the motors won't last too long with that current, imagine what will happen to the PCB

Chuckster...

Part of that design is that the charge pump only supplies the extra voltage to the motor ONLY, the PCB is ISOLATED from that extra voltage and runs off of its regulator and maintains standard voltage.

Using the same theory, does the person using an arc welder also have current flowing through them? Does the TV have to take the full flyback voltage through the entire circuit board? Does the person using the ESD shocker get shocked too? Its all about multiple grounds, current blocking, and isolation.

Look up some flyback and charge pump circuits and see how they work and find out for yourself.

Its a sound idea, a simple circuit, and is used everyday in your TV, your car ignition, even in the computer you are reading this on.

[cheesehead]

Why not just replace the stock cap? That could give the desired effect, and not put too much extra strain on the circut.