Wiring Photos

Please see this Parallax forum post for a good diagram of how to wire the HB-25’s, motors and encoders:

It is worth looking at the ActivityBot setup too: http://learn.parallax.com/activitybot/electrical-connections which explains the server connections, which are also used for the motor controllers, and the use of pull-up resistors.

Also this thread has some good information on the the “ActivityBot”code that I use to control the motors:

TODO: Write up a full wiring description with diagrams of every component . . .

The rest is just a collection of high resolution photos of the robot’s wiring. I hope these may help others imagine how to wire their ArloBot!

Click on each image for a full resolution version. Download them as you see fit and if you build a wiring diagram of your own please let me link to it! Or I can host it of course if you want.


















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He's just this guy, you know? Chris aka ChrisL8 aka the Hoopy Frood aka the Ekpyrotic Frood is a full time Unix Admin who likes to play with everything technology on the side. I mostly build robots here, but I also dabble in web development.

8 thoughts on “Wiring Photos”

  1. I have two “bus bars” on the robot. One for 12 volt negative and one for 12 volt positive. The entire bar is “linked” together with a bus connector, all form Radio Shack.
    The negative bus bar is exposed. You can see it toward the front of the robot.
    The positive bus bar is covered with a piece of plastic (cut from a flexible DVD holder). That is what that black plastic thing is behind the USB Relay board, it is just another bus covered with a thin piece of plastic to avoid accidental shorts. A 12 volt line connects it to the Arlo Power Supply and then anything that needs 12 volts can use that.

    The motor controllers have their own connection on the Arlo Power Supply, each of which goes to a separate relay on the USB Relay Controller and then on to the HB-25 controllers.

      1. jtilghman, please check out the two links I added to the bottom of the post. I hope they will explain the wiring for the encoders and motors.

  2. I used the arlodrive library. But drive_speed(left,right) doesn’t work under values 100. and also ones I call the drive_speed encoders starts to increment automatically. I can’t find the problem using the arlodrive. I also did the calibration. can you please suggest me anything.
    I have the same hardware configuration as you do.

    1. I was going to suggest you check the Parallax forum and ask there, but it looks like you already did.

      Can you post your code somewhere so we can see it? Perhaps put it in the forum in a post, either in the same thread or start a new one.

  3. Hi Chris,

    Have you checked the updated page on the Parallax about the ArloBot

    Now, Parallax is selling the ArloBot as a complete kit. All the parts that you used for this project are exactly the same except for the motor controller, which is now replaced by a DHB-10 Dual H-Bridge 10 Amp Motor Controller that can control two motors at the same time.
    The page is currently nicely written with complete assembly guide with pictures. So now my question is, will your code for the arlobot using ROS compatible with this new robot out of the box? What are your thoughts on this matter? I will be very interested to listen to your comments, as with the robot being sold as a complete kit, it becomes much easier to get your hands on a medium sized, decent powered semi outdoor ROS robot for research and education. Only thing missing is the ROS compatibility with this new kit which I think you have already done much of the work.

    Waiting for your reply.


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