Shop OBEX P1 Docs P2 Docs Learn Events
is it possible to use another motor controller instead of dhb-10 with activity board — Parallax Forums

is it possible to use another motor controller instead of dhb-10 with activity board

reinaldoreinaldo Posts: 71
edited 2020-09-23 16:24 in Robotics
im curious if there is another motor board that i could use instead of dhb-10 out their to collaborate with activity board.

Comments

  • Zillions of them.

    What sort of motors are you driving?

    I've used the MC33926 drivers with the Arlo motors.

    Any motor controller capable of driving the motors you want to use should be able to work with the Activity Board.
  • reinaldoreinaldo Posts: 71
    edited 2020-09-25 12:42
    im using the motors that come with the arlo robot kit. and can i program the board you recomend from the activity board or does it work with blocklyprop?
  • Hello reinaldo!

    I use the MC33926 motor driver board in my model railroad engine project.
    I have a schematic on the first post that is connected to an activity board WX, and I use the wx wifi module to serve up a html web page to control it all.
    You can probably use my posts as a reference on how to get it working.

    I have included the full schematic in jpg form and pdf form, and I also have attached a zip file with all the code the entire project uses.
    Its very easy to get the mc33926 polu motor board working!
    https://www.parallax.com/product/28820

    It looks like your motors are 12v at 3amp max, so that should work for you, my specific motor is powered at 16v and pulls 900mA max, and it works great!

    The board doesn't really get programmed, it just has pins that get set high or low, and then you PWM two pins for variable speeds.
    I can trim down my engine code if you want a bare-bones motor example.

    https://forums.parallax.com/discussion/172107/model-railroad-engine-controller-activityboardwx-dualmc33926-sound-smoke-axlesensor-14vdcc-supercap/p1
  • Duane DegnDuane Degn Posts: 10,588
    edited 2020-09-25 20:49
    reinaldo wrote: »
    im using the motors that come with the arlo robot kit.

    I've used the MC33926 dual driver to power the Arlo motors but most of the other h-bridge options I've seen have higher current ratings.

    In my experience the Arlo motors don't draw more than 2 amps so the 3 amp MC33629 should work OK but they're not overkill like many of the other solutions used with the motors.

    Here's a link to a post showing my robot with Arlo motors being powered by the dual MC33926.

    I was trying to replicate the older Eddie board when I used the MC33926 drivers. In order to use the same I/O pins as the Eddie board, I used a Quickstart board as the controller. I'm not sure if I've used the MC33926 with an Activity Board or not but I'm sure it would work just fine.

    Here's a link to my Github with the Arlo code. There are two archive files in the folder. One is the code I used with the QuickStart board and the MC33926 and the other is the code used with the Activity Board and HB-25 motor controllers.

    If you wanted to use Arlo code on the Activity Board using dual MC33926 drivers, you'd want a hybrid of the two versions of code.

    This hybrid of code sure seems like it would be useful to more than just yourself so I'll try to find some time to make another version of the Eddie/Arlo code.
    reinaldo wrote: »
    does it work with blocklyprop?

    I don't know about the Blockly option. I don't use Blockly enough to know.

  • If you want to keep your Blockly code the same, you could select a different motor controller which uses RC pulse inputs. I'll find a few and post links here.
  • If you search for "DC Motor ESC" you can find a lot of possible options. You want an ESC for DC motors and you want one with reverse.

    Here's one option from Pololu.

    Here's one for RC cars on Amazon.

    Hopefully someone more familiar with Blockly can tell us how hard it is to transition from servo pulse control to PWM used by the MC33926. This sort of change would be pretty simple in either Spin or C.
  • Thanks Duane your always a big help in my projects as well as ken gracey and I will order the motor controller soon my project is on hold for alittle bit .
  • Duane DegnDuane Degn Posts: 10,588
    edited 2020-09-26 20:47
    I just loaded Blockly onto my latest computer and I see there is a "PWM" option. Your program will likely require a bit of tweaking but I don't think it would be hard to use the dual MC33926 board or other h-bridge which takes PWM inputs.

    Edit: While adding PWM control wouldn't be hard, accurately controlling the speed of the motors won't be simple. It would require using encoder feedback to accurately control the speed of each motor. This should be possible with Blockly but it's certainly not trivial.
  • I've been thinking about this issue a bit more and realize I had been neglecting a very important fact. The DHB-10 is a smart controller and uses encoder feedback to control speed. All the controller I've mentioned don't monitor encoder feedback on their own. All the options mentioned in this thread control power and not speed.

    Your program will need to monitor the encoders and adjust the power output to obtain the desired speed. I've done this sort of thing many times using Spin but I'm not sure if the basic programming blocks of Blockly make this sort of programming loop possible.
  • i got it to work with a cytron board but now i want five pings to make the rc robot stop and be able to back up when i accelerate backwards
  • reinaldo wrote: »
    i got it to work with a cytron board but now i want five pings to make the rc robot stop and be able to back up when i accelerate backwards

    I imagine avoiding obstacles as you backup would be similar to the way forward obstacles are avoided. If you run into trouble, post your code so people can make suggestions.
  • thanks duane!!
Sign In or Register to comment.