i see now…since your
i see now…since your using relays you wouldnt need the cap to filter the engine noise
Correct. And also since we
Correct. And also since we do not understand what they do, so off they go!
Also because they make a good cracking sound if you crunch them!
**microcontroler **
I am new to the electronics of robotics and was wondering if it is possible to run more than the standard relays used to control the RC car from the microcontroller. For instance 2 or 3 of the same relay circuits from one chip. I have a project I am working on that needs a system that controls 5 motors and 10 sensors at the same time. There is a time difference between the motor controls at specific times of the robots functions but they have to be linked in some way. I am using a 12V power supply and 10 relays. Is it possible to run the microcontroller like this with out it being damaged. Any help on this would be greatly appreciated.
For controlling motors,
For controlling motors, you’d be better off using Transistors (assuming they can handle the current you need)
Or use some Darlington Arrays (7 transistors on 1 chip), can source up to 50v, 500ma per channel. Much smaller and less of a hassle than Relays. And with most relays, you’ll need a Voltage Blowback Diode, which protects the microcontroller from the voltage spikes that the Relay causes when it clicks on and off.
Yes it’s very possible, just need to look for the right thing!
Also, are you wanting to be able to control the speed of each motor? If so, you’d be better off doing a google search for H-Bridge, or just buy some H-bridges!(SN754410NE, or L293D, L298Ds… etc etc, there’s a few!)
Best of luck, I hope I didn’t miss too much 
You should take a look at
You should take a look at the Start here link at the top of this site for a quick intro to motor and sensor control with a microcontroller.
As CaptainObvious posted, yes it is definitely possible. Take a look around the site, including the FAQ and you will get lots of ideas to help you get started.
thanx a bunch for the info.
thanx a bunch for the info. really helped a lot.
**ignition system **
Hello people.
I am almost finished with my robot. Just ran into another speed bump that I can’t seem to get over. I want to make an electronic ignition system for a mounted potato gun on my robot.Ha-ha. But as always the gas in the combustion chamber doesn’t always ignite as I would have hopped it would. I am using a 12volt system and was wondering if it is possible to make use of op amps and transistors or any other small components to get from 12volt to about 500volt. A regular car coil does this with ease but it is too large. Any detailed information would be greatly appreciated.
race walls, not guns
Hallo Jan,
Please post your question in the forums. Potato guns have little to with the page you are asking your question on.I am sure someone will be able to answer it there.
Rik
Do you have any idea what
Do you have any idea what you are doing? You could kill somebody with a potato gun. Ha ha. If you googled, you could have found a plethora of things to increase the voltage with.
Ha-ha. To tell you the truth
Ha-ha. To tell you the truth I have some idea, but it is very limited to the power of this particular gun. I did the math and luckily I won’t blow myself up, but it mite of dean a bit over kill. Do you know of any sensors I can use to judge distance with? I have I really cul idea for this thing of mine. But I need it to judge distance and possibly detect movement from up to 50 yards. I can do the coding for it all I just need to get to grips with how the sensor will detect distance and if possible movement. I goggled my as off for this and I dint find any thing. Maybe I am just looking on the wrong places or it is a closely graded secret, its suppose to be on the net. Thanx for the help on the previous topic.
To detect movement of up to
To detect movement of up to 50 yards, you will need not only a sweeping sensor (PIR won’t reach that far) but a Laser range finder. Affordable sonar sensors of 20 feet cost around 30 dollars, so your up to your own to find that. As for the voltage generator, my best solution would be a flyback transformer, capable of 25kV at 30mA. It’s long arc’s (if tuned properly) can ignite airbourne gasses.
Flyback transformers:
thanx a lot. i really
thanx a lot. i really appreciate it.
Relays
Is it possible to use these relays http://www.radioshack.com/product/index.jsp?productId=2062481
coil rating
Try to find a relay that can be switched by the voltage of your batteries. You linked to a relay that takes 12 V up the coil. Not a likely voltage in a small car like these.
i understand
ok i understand now, thanks!
Do not use big RC’s
Please read this if you are going to build: https://www.robotshop.com/letsmakerobots/node/696#comment-40531
transistors
im curious, why did you not use transistors, instead of relays?
seems like alot less hassle to me.
great robot though, if i can get the time, il probably build a couple XD
Well, first of all I did not
Well, first of all I did not know of transistors at the time 
Second, I think they would get hot, and I would not have the clean “from battery to motor” that I liked.
I could of course just have used a standard motor driver, but all in all, I liked this, and I do not think it was more complicated, on the contrary, would use them again if I was to do this again.
Arh, I dont have a good explenation! Just feels better :)
il prolly use transistors
il prolly use transistors then.
you can just use a small piece of any metal as a heatsink, wich would give them alot more power 
and i think it would be easyer, only 3 pins to conect, well its probably easyer for me, since i know zip 'bout relays
by the way, is this the board you used? http://81.134.141.187/epages/Store.storefront/?ObjectPath=/Shops/Store.TechSupplies/Products/AXE020
Yes, that is the board I was
Yes, that is the board I was using.
- How are you going to make it reverse?
- When the car is driving by it’s own, because of the speed, and you are reversing, to make it skid, how will your transistors handle the current flowing back? (My rechargable batteries are charged when this happens, because I use relays, but the transistors would not be happy, would they?)
- How many amps can you take through the transistors? And what do your motors draw?