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Buggy only reverses

Posted: Wed Jul 18, 2007 8:57 am
by steamydave
Hi,

I've used the example flowcode to get the buggy moving with PWM - in reverse (assuming the line following module is at the "front"), but not forwards.

Also, using the turn example, the buggy turns with one motor stopped, and one turning instead of them going opposite directions, so again, the forwards part isn't working!

Many thanks,

Dave

Posted: Wed Jul 18, 2007 9:21 am
by Benj
Hello

Thats strange. Can you please confirm the following.

1) The motor connections are the correct way round. Eg the red lead goes to the +.

2) The Motor direction output pins are set to logic 1.

3) The PWM is running at under 50% mark and over 50% space.

We are releasing an update for Flowcode today hopefully which will contain the Formula Flowcode Component.

Still stuck in reverse

Posted: Sun Jul 29, 2007 3:37 pm
by steamydave
Hi Ben,

Well done to you all for the new components for the Buggy. The components and test routines are fantastic.

Right, I still have the same problem with the buggy using the new components. Assuming the line-following circuit is at the "front" of the buggy, then...

"Forwards" component makes the buggy go backwards, "Backwards" doesn't drive the motors at all.

From this, I assume the turning won't work as it requires a mixture of forwards and reverse.

Red motor wires are going to +, black to -

Will post photos once I have uploaded the photos. The Forward/reverse component are both using the suggested value of 200

Any suggestions or more information required?

Dave

Posted: Sun Jul 29, 2007 7:07 pm
by steamydave
Sorry about the photo focus - think you can see that the connections are correct...
Image
Image

Dave

Posted: Sun Jul 29, 2007 9:24 pm
by steamydave
Odd now!

For some reason, the "reverse" component is now working - forwards!

I put a meter over the pins of the motors whilst in "forwards" mode (200) and the meter was reporting a voltage of -1.99v - I guess thats why the motors are running backwards, but it doesn't explain why the other component has started running!

"SpinRight" does make it spin right now - ? odd again, as I would expect it to go left if the voltages are reversed?!

I'm puzzled now, but will continue to test with what I can!

Dave

Posted: Mon Jul 30, 2007 10:15 am
by Benj
Hello Dave

when assembling the Buggy did you cross over the wires for the motors as specified in the build instructions 2.4 and 2.5.

http://www.matrixmultimedia.com/softwar ... tarted.pdf

Posted: Mon Jul 30, 2007 10:48 am
by steamydave
Hi Ben,

Looks like that may be the problem! :lol:

Thanks Ben. I had already attached the board to the chassis before I made the electrical connections. When the board is the correct way up, the cross over doesn't happen - the left connection is above the left motor etc. :shock:

I either didn't read the instructions in time, or hadn't found them!!! :roll:

Not only do the motors go the right way now (!), but also some of the slack wire is taken up as it now travels over the chassis.

Many thanks for the help, and apologies for the "rookie" error. :roll:

ALWAYS READ THE INSTRUCTIONS FIRST!!!! Duh!:oops: :wink:
Dave

Posted: Mon Jul 30, 2007 11:08 am
by Benj
Hello Dave

Don't worry it was bound to happen to someone sooner or later.

Thanks for letting us know that it is all working correctly now.

Hope you have fun with your Micro-mouse now it is running correctly. :)

Posted: Wed Sep 05, 2007 5:14 pm
by cleverchip
Hmm... the instructions are a little confusing though. The designation 'left' and 'right' would normally be taken as viewed 'looking forwards' (ie in the direction the buggy moves forwards). This would make each motor connect to the circuit board without crossing over the chassis.

I made precisely the same 'error' as steamydave (and no, I didn't look at the instructions!). Following the diagram (crossing the motor wires over the chassis) is easy enough, but perhaps it could be made clearer by pointing out that where it says 'right motor' on the circuit board... you actually mean't 'left motor' !!

Posted: Wed Sep 05, 2007 5:19 pm
by Benj
Hello

The labels are correct. The wires enter the backs of the motors. This is why the wires require a crossover.

The right motor connections go from the right hand side of the buggy to the left hand side of the chassis. These then enter the back of the motor. The front of the motor comes out as the right hand wheel.

Posted: Wed Sep 05, 2007 5:59 pm
by cleverchip
Thanks, Benj.

I'm sure I'm not the first to assume that the wires emerge from the chassis adjacent to the wheel (whose motor) they are connected to!

Cheers!

Posted: Thu Sep 06, 2007 10:02 am
by Benj
Your right. They had me stumped for a while too. :D