Cheap RC system for RC toys

Team Orr · Post by **Team Orr** » Fri Apr 01, 2011 2:51 pm

HI all,
I have been in contact with a awesome guy called Jaimie Mantzel (youtube here: http://www.youtube.com/user/JMEMantzel he's building a giant robot, sweet!) anyway he is also designing some RC robot kits that are based around the same design as his Giant robot, a spider styled walker. he has all the parts assembled and is now in need of some RC stuff, if you watch his videos you will soon realise he is on a tight budget (he lives out in the middle of the woods...with no electricity exept solar energy and a generator) so he's looking to get some on the cheap, similar style to the chinease RC toys. He ran it by me and i told him i would run it by you guys. This was his responce:

If you could run the RC stuff by your peoples, that would be great! Ok, here's what i basicly need...

-No servos. So like... the reciever has wires that go straight to motor. (which, sort of it a servo.. infinite rotation one, but you know what I mean, not a bang bang setup with microswitches
-The motors run on 6-ish volts. You know, like 4 AA batteries, which varies depending on the battery type.
-Pretty cheap...? ....but still working pretty well.
-more than 2 different frequencies would be really nice. Like.... 5 or 10 would be awesome

ao we're looking for a cheap, easy, chinease style RC controll with no frills or anything, either easy to assemble or a direct supplyer to a company? i think we need a built in ESC, thought you are the guys to ask, he's looking to sell them as kits to fund the GRP (giant robot project) so easy availability would be key.

any help would be great!
Jack

daliad100 · Post by **daliad100** » Fri Apr 01, 2011 5:28 pm

Cheap rc toys typically use variations of the TX2B and RX2B chips that take in up to 5 switch based inputs and provide 5 on/off outputs.

The nice thing about them is that they can be configured for infrared control which is a much simpler circuit that requires far fewer parts than a radio.

It also appears that it would be easier to tune because all that really needs to be done is change the resistor that sets the frequency.

I've personally tried to cut the output pins of the IC off of the reciever board of a cheap rc car to allow me to piggyback a larger Hbridge off it for some fun robots but I don't think that the current draw will be too large in a machine like that so hooking the motors straight up to the rc car's board shouldn't be too much of a problem.

Team Orr · Post by **Team Orr** » Sat Apr 02, 2011 4:30 pm

Thanks, so what other components would we need apart from the tx2b and rx2b chips? as i presume its not just them? a link or diagram of sorts would be much appreciated

do you think its somthing that can be done at home or in a reasonablty well equipped workshop? I.E not a mega factory laboratory thing

any more advice would be great!
Jack

earthwormjim · Post by **earthwormjim** » Sat Apr 02, 2011 5:25 pm

How about something like this...
http://www.robots-dreams.com/2005/01/co ... g_you.html
An IR remote and reciever module,that would take some work,but could be a good solution,I think.

(I would like to buy a hardware only kit spider robot,and figure out some kind of processor controlled autonomous controller,as a project!!

)

daliad100 · Post by **daliad100** » Sat Apr 02, 2011 5:27 pm

Here is the data sheet for both chipshttp://elakatos.home.comcast.net/~elaka ... p-Spec.pdf

It contains circuit diagrams on how to use the chips (page 8 has the ir circuits) and a photodiode will do for the "ir reciever".

http://www.silan.com.cn/english/product ... 5%E8%B7%AF - a link to the manufacturer's page.

If the chips can be bought in a dip package rather than an smd one they can much more easilly be soldered by hand.

Alternatively buying a stupid number of cheap rc cars wholesale and hacking the motor outputs to the robots motors might work.