Mr. First Robot

Let's Make Robots Robots
1

I've been reading all the great info on this website for the last month or so. Was inspired to put together the first 'start here' robot.

I followed the recommendations, went with a PICAXE 28X1 as the brains, also the Sharp IR sensor. The rest was within the ballpark of recommendations.

 

Here is a picture of how everything looked yesterday and my kids (2 girls) and I put together the gearbox & motors, put the wheels on and got the chips on the board.

 

My girls are really excited. I spent time going over the PICAXE Starter board (using the info on the website, which is GREAT by the way) and explained how things work, what is power vs ground, digital input vs analog and stuff like that. I wanted to have something to reference as we go through the whole thing together.

I have always wanted to build a robot, but just never got around to it. Then I found this site about a month ago and shortly after we were talking about what to do over the Christmas Holiday and I suggested we build a robot. My kids said 'YES!' so I went and ordered the parts from Sparkfun.com and we just got em on Thursday. So, Friday night (last night) we started.

UPDATE 12/13/2009:

We have completed Mr. First Robot, took about 6-7 hours but it was a great learning experience for all of us.

We had a couple of challenges as we went through, first was getting the USB cable to work with my MPB. This turned out to be the only one that didn't get addressed. After numerous attempts, I ended up pulling out the work laptop (MS XP) and I was able to get the cable/program running pretty easily. Still not sure what the problem is with the MBP, but we adapted and overcame (or worked around it...).

We started with confirming all the basic parts worked/operated as expected, figured out the commands for movement and then set about having him drive forward until he 'spotted' something, then stop. Then we started looking around, followed by turning. We had challenges with the sensor input, but I think it had to do with not putting jumpers on the other analog inputs. We also had to change out the cabinet knob, it was too heavy so we switched to an unused Christmas ornament. We just cut off part of the top and used hot glue to get it in place, look see the new robot booty:

We still need to work through the code, clean it up and whatnot. It's not running in an ideal state, but we did accomplish our first objective.

Navigate via IR, version 2 will also remove the pits from olives... We cannot tolerate any pits.

  • Actuators / output devices: Tamiya twin gearbox
  • Control method: autonomous
  • CPU: Picaxe 28x1
  • Operating system: Mac OS X
  • Power source: 3 AA cells
  • Programming language: Picaxe basic
  • Sensors / input devices: SHARP IR sensor - GP2D120XJ00F
  • Target environment: indoor
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/mr-first-robot
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Hey DarkPassenger ("Dexter"

Hey DarkPassenger (“Dexter” books/series reference?), welcome to LMR =)

Looks like you’re well underway with your team effort robot project - the only thing that might be missing from your photo is something to put on the front to slide around on, unless you’re able to balance the bot well enough to keep the nose off the ground. Nice rubber wheels by the way. Good to see you’ve got a big roll of double-sided foam tape, that stuff’s great =D

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Hi and welcome Dark passenger

What a great way to lead up to xmas.

I noticed I dont see the 16pin 330 DIL resistor for your servo, (or are you using a single resistor).

I see your gearbox there is similar to mine. I have the tamia double gearbox that comes with four gear ratio assemblies.

I am just curious to know what your final ratio is or what speed do the shafts rotate at. I think yours is different to mine as mine hase some blue and yellow gears in it.

Also what make and size are those wheels? Are they also Tamia?

Be sure to grease up those gears. It quitens them down a lot and helps them last a lot longer.
I used an ear bud and some white petroleum jelly to lightly coat all the teeth. Too much grease will attract dust and fluff.

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Hello, and thanks for the welcome.

Yes, DarkPassenger is a reference to the books/TV series (both of which are great).

We made a little bit more progress today, I’ll have those photos up tomorrow I think. TeleFox, I was planning to use metal cabinet knob I have, see how that goes. The twin gearbox is now mounted on a tempered MDF board and we’re figuring out the layout of the other items.

G_code, we do have a single 330 resistor in there and the ratio on the twin gearbox we have is 203:1 (the other option is 58:1). We talked about how the power is converted by the different ratios, putting it together was a blast. The wheels work with either a hex shaft (like the one we have) or a smooth shaft… It’s not Tamiya, I think but some other Japanese company (if I recall the package correctly). The gears have been greased, but we did run out so thanks for the advice to use petroleum jelly, we’ll do that tomorrow.

Hope to have it up and running by tomorrow afternoon, have to do some soldering and then we can get it running. At the rate we are going I may have to purchase some more parts so we can build another robot before the holiday is done… We have 2 full weeks off, so I gotta try to keep them going. They want to bring the robots into school after the new year to show their teachers. I wish I would have known a while ago how excited my kids would get about it, we would have started earlier!

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Latest progress

So, I finally got the latest pictures of the ‘semi-assembled’ bot:

|x

This is from the backside, seeing the cabinet knob used as the third wheel. I had bought a caster, but it's really, really small and I don't think it will work.

Here is from the front, alas the servo and sensor are not yet mounted. That will be later today, after the girls finish up baking cookies:

|x

If we get Mr. First Robot running we'll be sure to get video of his 'first steps'... He's growing so fast.

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Getting closer

And after another hour with my oldest daughter we now have Mr. First Robot coming together:

|x

And now... to quote Frits, 'Let there be life'. Let the fun begin.

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The red Christmas ornament
The red Christmas ornament for the wheel looks like a bullfrog’s throat all puffed up. If you decide to treat that end as the front, you have a cool red frog theme to build on.

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um

great bot dose any body else not see the shout box

doubled sided tape =awsome!

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Thanks again to everyone!

We’ll have to see if I keep up with the kids, or if THEY keep up with me. I have given them the basic code we wrote, so they could review it and think about what other things to have the robot do. Haven’t heard anything yet.

In the meantime, I decided to put in another order to Sparkfun.com for another roster of robot parts (and assorted other bits). That should keep us busy through till the New Year…

Fun site, glad to have joined. Have a great holiday everyone!

Time to get back to troubleshooting the analog input for additional noise.