robohobo
hello all, im in the process of building my first ez robot and ive realized how much i truly have to learn at once. anyway when i ordered my rover 5 chassis (4 motor w/ encoders model) i opted to go with the dagu 4ch motor driver since it supported the encoders. i now realize that as a beginner wanting to jump in head first this wasnt the best idea. im fairly certain ive figured out how to correctly connect the driver to ez-b and both to my 6v sla power source, but if anyone has a diagram of how to do this properly i would feel more comfortable. my major problem is scripting a custom control panel to drive this thing. i have no clue what im doing and a push in the right direction would be greatly appreciated.
maybe DJ will add this motor controller in a future update? as i understand it ez-robot works very closely with dagu and carrys the rover 5 in store so it seems likely. ill cross my fingers.
@Rich : Purchased mine from RoboSavvy. You can buy from their website or their Ebay store.
The website prices are lower, but I think the shipping is higher. I guess it probably balances out.
@Bill Thanks.
@RoboHobo great news
To stop, it looks like you will need to use @RobertL184's script.
Thank you all very much. @Rich especially for taking so much time to help me. Project post within the week I'd say. =)
You're more than welcome. Looking forward to see the project
Okay! So my dagu+board turned up today, and after work I set about getting it all wired together. I followed Rich's example from the first forum page, then figured out how to wire the power on and what went where.
So, did it work? Well, yes. Ish.
Problem 1, the plugs on the Dagu chassis' motors are backwards. They are one-way only plugs, so connect only one way to the board. But when plugged in thusly, the red wire is on the gnd pin, not the red one. Without un-crimping/re-crimping the plugs, they will always be backwards. Thankfully, as I udnerstand, that doesn't matter really. It just means everything backwards.
Anywho, problem 2...
With all 4 motors hooked up, the pairs need their directions reversed relative to each other, otherwise the script fails.
If we say for arguments sake, the motors are labelled thusly; ^Front^ 1-----3 | | | | | | 2-----4
(Warning, weird pseudo-code coming up!)
In this case, motor 1 has to be set Dir(0) with motor 2 Dir(1), otherwise they both turn opposite directions, resulting in a whole lot of unhappy motor-fairies. Could this be a result of the weird plugs, I don't know. The same goes for 3 and 4. As a result, the custom Movement Panel doesn't work (It sets all to off or on). Obviously, this fix is quick and simple.
Problem 3... For some reason, when using the Stop button on the custom movement panel, none of the motors stop turning. In addition, if you slide quickly from ON to OFF on a PWM slider, the motor doesn't stop. Only when going gradually from top to bottom does it shut off. It's almost like it needs to hit 1% then 0% to turn it off. I don't know if this is a Dagu issue or an EZB issue.
Anywho, I'm exhausted from work, so I'm going to fiddle again tomorrow.
Hope some of this makes sense!
^^^Addition...
I so should've read the rest of the forum post before putting up my post. I see from Robert's script that he already addressed the stopping issue.
Makes me wonder, why is this the case? Is it dagu or ezb based, and would kicking it help?
I'm wondering, (It's early, forgive me!).. Can everything share a common ground? Could I, for example, take D0 gnd to a breadboard, and put all the grounds on to that? With the way Robert has it, one channel for PWM (Makes sense, you want them all going the same speed in the end), then the channels paired off (1,3 / 2,4) for dir, and then a common ground, it'll require only three EzB outputs to be used?
..So I thought before re-wiring, I would try editing Rich's script, to try and get the directions right etc. I hooked up the logic power, then connected the motor power and had an unexpected encounter with Puff the Magic Smoke. :/ Thankfully from the Dagu board, not the EzB. No idea why, though. Checked, double-checked, triple-checked the wiring, everything okay.
Unhooked everything, plugged in Logic power, then motor power and a second coming of Puff, some more magic smoke. :/
Bummer.