Hello, please help me drag my sorry self into the 21st century

[magicgeorge]

Firstly, this is my first post here, so hello everybody. Nice to be here.
hm:i, What a nice place you have here, I've been reading the boards :mu:a and a half.

I had a keen interest in robotics and electronics when I was a pup and have recently rekindled my interest after recovering my old Tomy omnibot from my parents attic and deciding to make him into 'something'.

As a child, I had a pretty good handle on all the basics except transistors (they're a switch, they're 2 diodes back to back, they're amplifiers, they're little tripods for cockroach's cameras) so I would build all my memory systems or logic gates using relays.

Coming across your board I was delighted to find lots of diagrams and usefull info on H bridge circuits for motors. I've built one and it works well, so thank you.

Here's my problem. I am first going to make my omnibot a radio controlled robot and later add the computer commands via a duplicate remote. I want the omnibot to have the same movements as the original.
Forward, backwards, revolve left, revolve right. This will mean I want for switches to activate the following switches in my H bridge circuit:
Calling the switches in the left hand h S1 and S2 and in the right hand s1 and s2
Forward: S1 & s1
Backward:S2 & s2
left: S1 & s2
Right S2 and s1

My question is, is there a simple way of making 4 inputs activate those 4 combinations without slipping back into my ancient ways and using a bunch of relays.

Thanks in advance for any help.

George

 

[Robot builder 101]

is this your first robotic/microcontroller project? if so, I would do some other projects before you jump too far into robotics.

 

[magicgeorge]

Well it's my first one in about 19 years.
I thought this was a fairly simple project. A 4 input, 4 output problem, is the solution really going to be that complicated? What would you recommend to ween me into it?

There's no rush I can play around with a few ciruits before actually applying the method to the machine.
George

 

[Pommie]

Google HT12 (HT12E = encoder, HT12D = decoder). It is a 4 button encoder that can be connected to an RF transmitter/receiver combo. Whichever combination of buttons you press on the transmitter end makes the corresponding output active.

Mike.

 

[magicgeorge]

Cheers Mike.
I think I've already got that part sorted. I've got as far as sending 6 inputs on my remote to 6 outputs on the reciever. My problem lies inbetween the output and the 2 H-bridges. I think I could probably solve it using a chip with logic gates in it but I thought there might be a simpler solution with a few diodes and a bit of thinking. I could also solve the problem using relays but, as I said, I'm trying to get away from that.

I wasn't very clear in my original post. When I said "making 4 inputs activate those 4 combinations". I was refering to the outputs in the RF combo but meant inputs as in 'inputs into the recieving circuit'.

I'm probably not expressing myself very clearly. Sorry.
George

 

[magicgeorge]

hello
If any one is interested. I managed to solve my problem using 8 additional transistors.
George