hi again, thanks for all your help
the reason i didnt go for a microcontroller is that i really wanted to keep costs down as much as possible.. also, i'm more interested in learning how to go about doing it this way than programming it using code..
just to clarify the objective:
device is placed at the starting zone
device is triggered by a single physical motion (flick a switch, whatever)
device drives forward (approx 2m)
device stops and waits while it receives payload
device drives back to start
device stops
and thats it.. pretty simple really, i need to decide whether to time the whole thing in timed stages, or time the drive and then start the drive back when the payload is transferred..
i used CEDAR logic simulator to design a simple circuit using a 4 bit binary counter, 3 D flip-flops and a bunch of AND gates (see attachment)
im planning to use a 74LS161 4-bit binary counter and a 4076 quad D flip-flop IC. If it isn't clear how the circuit works, basically each time the counter counts a cycle, it changes the state of the D-flip flops, and then i used logic gates to determine the action that is desired..
basically, it goes forward for 16 counts, stops for 32, and reverses for another 16 and then stops completely..
is this a good way of doing it? or have i overcomplicated the situation?
then i need to use the logic to actually trigger the h-bridge itself..
ive had a look on the internet, and one of simplest circuits i could find is this one (see attached) that i took from (
The Using MOSFETS Website: H-bridge using P and N channel FETs).
would this be suitable for my purposes?
would mosfets IRF9540N and IRF1405 be good to use? also, i am not entirely sure about the difference between mosfets and just standard fets.. would it be ok to use a standard N and P FET in this circuit as opposed to the more costly mosfet?
sorry for having so many questions!!
once again, any help at all would be appreciated..
cheers
gus