MakerFaire Workshop Bot - Prototype

 


Update: 2012-09-07: Chris the Carpenter has his prototype all done. 

 

 

 


 

This is a prototype for the Robot Building Workshop Chris the Carpenter and I are going to run at MakerFaire 2012 NYC.

This early prototype is just a couple of 2 in. x 3 1/4 in. plexiglass pieces. Chris is working on the design for the chassis. In the meantime, this will let me experiment with some code.

 

The dimensions were choosen to get the wheels on about 3 1/4 in. center, which is the same as the length front to back. 

I drilled some holes in the top deck to run wires.

 

The wheels are bottle caps, which I drilled and attached with #2 sheet metal screws and lock washers.

 

 

Two front mounted bumper switches let the robot know if it has hit anything. Note that the bumpers extend to be even with the outer edges of the wheels. I used this tip so that I could use separate digital inputs for each switch.

 

We probably won't bother with this for MakerFaire, but I included a remote switch to select between 'run' and 'program' on the AXE023 board. It's a pain to move the little jumper.

Prototype for the LMR Robot Building Workshop at MakerFaire

  • Actuators / output devices: Solarbotics GM8 gear motors
  • CPU: PICAXE AXE023, 08M2
  • Power source: 3xAAA alkaline batteries
  • Sensors / input devices: 2 Bumper switches
  • Target environment: quite smooth flat surfaces

This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/makerfaire-workshop-bot-prototype

What kind of touch sensors?

What kind of touch sensors are those?

Those are called 'snap

Those are called ‘snap switches’, which make great bump sensors.

They have one common terminal, one normally connected, and one normally open. I have them wired to the AXE023 board between the common and normally open terminals.

Any reason why you are using

Any reason why you are using those limit switches as opposed to something similar to the BOEbot ‘whiskers’? They are a stiff wire that shorts out a group of header pins. It’s quite cool really :slight_smile:

Here’s a video of whisker example: http://www.youtube.com/watch?v=IFKhD1_GB00

How much will it cost a kid/group to make this bot at MF? How long does it take you to make this into a kit (not making the kit, but getting all the pieces together)?

Well, snap switches are

Well, snap switches are pretty cheap, and very reliable. I’ve seen/used whiskers before, but it just didn’t occur to me to use them on this one. Maybe I’ll give it a try. Dirt cheap, if it works out.

This will be a free event at MakerFaire. We got parts and some funds donated to us by Picaxe! We’ll have enough for 100 kits.

I’m hoping we can get the kids through a build in an hour, but I’ll need to do some testing once the kit is complete.

You could always go for

You could always go for somewhere in between - it’s not hard to solder a short length of solid wire to the metal lever on the micro switch, provided you have a soldering iron that can deliver a little heat =)

Might be a nice way to customise these little bots, which I have to say look really nice and easy to put together. Good work IG.

Thanks, TF.You can

Thanks, TF.

You can definitely extend the actuators on these switches, but it is probably not necessary on these particular ones.What I get for the kit will be a little different, since these are just parts I had lying around.

These particular switches extend far enough out and to the front that no extra extension is needed.  

Wow, do you mind when I

Wow, do you mind when I steal your design to have it in a workshop in Berlin as well? I would just use other (smaller) motors.

The design is hardly

The design is hardly proprietary. Steal with both hands!

I can’t wait for the Maker Faire this year.

I should be able to hang around the table a bit longer this year then last year.  Maybe even help a little if you need it or bring a bot or 2…  I’m working on one now that sould be done by the faire. 

Great project by the way.  Looks great.

Hey, looking forward to

Hey, looking forward to seeing you again. I hope you can hang for a while. We will definitely need some help.

Also, I haven’t forgotten that I owe you an LMR MakerFaire t-shirt. I didn’t want to send you just the iron-on, because they were so challenging to put on without making a mistake. I’ll bring the iron-ons to the event and you can take on or two if you want them. 

Also, we will definitely have finished shirts for the volunteers who can stick around and help with with running our table. 

Sooo

I’ll be at the faire on Sunday all day. Can’t wait to meet you guys in person. Are dogs allowed? Seems I have seen them in videos.

Cool, see you there. I think

Cool, see you there. I think dogs are OK, but check the Maker Faire site to be sure.

Video!!
Video!!

OK. I linked my Maker Faire

OK. I linked my Maker Faire promo video, which includes some footage of this little guy in action. Sorry to make you sit through the commercial as well.

The Person Behind the Username

Great to read that the LMR US Division meets up in New York. It’s nice to know the person behind the username.

good job, I am looking for

good job, I am looking for some materials for my car’s wheel~~

Ideas for wheels

  • Bottle caps
  • Plastic/wood/whatever cut with a hole saw (e.g., plastic cutting board)
  • Wheels from a toy car
  • CDs or DVD (might be too big for this project)
  • Thick cardboard, foamboard, etc.
  • Use rubber bands for traction if the material is too smooth
  • Use built-up layers of hot glue to for traction or to make a wheel have a larger diameter