Build a Real Robot - Episode 9 - Motor Controllers Part 2

In episode nine of the Build a Real Robot series we will build the Motor Controller board.

The motor controller is built! It has been constructed using two Arduino Nanos and is wired up and ready to test.

Today I will show you the schematic of the controller and also how I hooked everything up on a small piece of perfboard. I’ll also explain why I decided to use the Arduino Nanos instead of Pro Minis of ATmega328P chips.

Also, there was a bit of a foul-up in last weeks video, it ended way too soon. An editing error that I apologize for.

The error also prevented you from hearing a question I posed to you regarding a way of exchanging information about the robot project, as well as your own robot builds. I asked the question again at the beginning of this video, so please leave me your comments - I’d love to get your opinions.

Now that the controller is built it’s time to move on to the software. I’ll be showing you some sketches in the next episode.

Hope you enjoy the video!

[Scriven]

Love the board identification trick, very cool! "Left Low, Right High".

[MysticDreamer]

A DroneBot Workshop forum would be quite interesting. As you point out viewers will be able to share with each other what they are doing. How you manage so many things is beyond me. You already have the two video series that you put out weekly. Plus the wonderfully well-organized companion web site pages. You're already performing at a super-human level and now you want to start a forum on top of that. I just don't know how you do it Bill. You must be on some kind of adrenaline high. If you start a forum I'll certainly be among the first to join it. It would be nice to see the robots your fans are building. We can also answer each other's questions on many things as well.



I would suggest that in addition to moderators you also get someone to monitor the content of forums and keep you alerted to the main topics that are being brought up. Kind of like a forum "secretary" so-to-speak. I'm quite certain that one of you viewers would be more happy to volunteer to provide you with that service. That way you wouldn't need to try to keep up with all the posts on the forums yourself.

[itisonlyadream]

I was sorry to hear about the setbacks you've had to deal with at your workshop. And yet, you've managed to continue on with this series with barely a hitch, when others wouldn't have had the dedication needed to pull it off. I love your idea about the forum and I'm all for it. However, I'm watching these videos in sequence, without jumping ahead, and I may find out later that the forum is already up and running.

[TiptreeJams]

No problem re the last video, you are human and not a robot :). A forum sounds great but I agree it needs a reliable moderator to manage its structure, filter out spam, and to deal with any 'heated' discussions where there is disagreement on a topic.

[azyfloof]

States of emergency going on, and yet you keep trucking! Hope you take care of YOURself, Bill!
A forum sounds like a great idea! Even something like a Discord would be great for chatting, collaborating, sharing ideas etc :)

[soumitradey]

Great ! Looking forward to motor control, soft start, stop and decelerating on sensing obstacle with distance less than "x" . That will be a great learning Sir.

[tinkmarshino]

Geez Bill you take care of yourself!! Floods on top of everything else? havens you need to come out to the pacific northwest.. we only have volcanoes once in a while.. no floods or anything like that. Thanks for your boost in confidence with the perfboard... at my age my hands shake a bit but I believe I can do this to.. carry on my friend and thanks so much for your sharing . Carry on and we will see you saturday..

[rgmtb]

A forum would be great! My projects span both Arduino and Raspberry Pi so having one place that I can ask question on both would be great! Also, I'm very new to this hobby in general so a place that was not very intimidating would be very helpful to me :-)

[EdwaltvanOostenbrugge]

it would be very much appreciated if you make a video about perimeter wire and auto docking to charge the robot. Your videos are great and easy to follow.

[bigg]

it would be very much appreciated if you make a video about PID and motor controlling

[K-]

Will feeding 5 volts to the Vin pin of the Nano instead of the minimum recommended of 7 volts be a problem?
Vin is feeding a regulator which needs about a 2 volt headroom. Great channel BTW.

[SteveRaynerMakes]

Sorry if someone has already asked this. How did you decide on the size of the capacitor?

[SufiShahHamidJalali]

Hi DroneBot, that is very interesting, however, I have a suggestion and that is if you could add a remote control mechanism to your robot with low latency FPV; I think it would be a far more attractive robot. Thank you.
These two things are very popular in serious robotics. Your presentations are excellent by the way! :)

[amandaborman]

With the 5V connected that way you can power the whole robot 5V through the Nano USB port. I know because I did it. It's not good.

[moathnaji]

I think that very important to make a series of tutorials about Automate with dc relays

[TheSkogemann]

No matter what kind of communication platform you choose, you are going to need moderators. I am all for a forum though, as it is very searchable and easy to maintain.
I would also recommend a Discord or Slack channel for chat (even voice chat).
I am looking forward to whatever you choose as i have a couple of projects i want to share. :-)

[srduke]

A forum is an excellent idea and I'd be more than happy to be one of your moderators. I've previous experience at moderating (and administrating) message boards so, hopefully, could be of valuable assistance to you.

[greaser]

Really enjoying this series. From the 'Bizarre Coincidence' department: Something like 20 years ago I bought a basic robotics book. I had read it at the time and was preparing a build project, but then the UK 'Cybot' partwork magazine came out, so I proceeded to lose the book amongst the junk in my house. Many years pass, my oldest boy was studying software engineering, and I was trying to find the book (without success) to give us something to talk about and maybe help to expand his horizons a bit (this was like 6 years ago). I wasn't a subscriber here but, coincidentally, the 2nd or 3rd video in this series popped up in my 'suggested' feed the very same day I found the book, which was David Heiserman's "How to Build Your Own Self-programming Robot", it used an 8085 processor and plenty of glue logic for I/O. So far in this video series discussion has seen some interesting parallels (e.g. there are only so many ways to implement a mobile platform on a sensible budget) with that book, and some even more interesting differences that highlight the development of hardware (especially for the 'maker' market) in the years since the book was published. I await the central software component of this project with bated breath :)

[soumitradey]

Sir, if we are using 4 motor for robot in case plesse also cover I2c interface with SDA SCL . 4 nano for front and rear

[PIXscotland]

An E-Stop should ideally not be linked to some logic/processing where possible. I'd recommend latching it to either cut the power or to reset the controllers. Adding it this way means that the processor can't really ignore an emergency. It also ensures a mistake in the programming won't cause the E-Stop to not operate. This isn't exactly the biggest or most dangerous robotic device, but it would be best to follow the safest option.