I like to equate projects (be they robotics, lawn work, or woodworking) to cooking. You take a bunch of things that are pretty interesting, and combine them into a cohesive unit to do things that the constituent parts cannot accomplish. In cooking this is done by combining flavors and spices and such to create a dish truly your own (Mom’s Tuna Casserole for one, I still can’t recreate it right). In woodworking it’s done by knowing the properties of the wood(s) you are using, and having a bunch of liquid nails and screws to make it into something cool (Grandpa’s Boxes of Days Past). In robotics, it is just as true. A servo is cool, so is an LED, and sure you can apply power to an LED and sure as the sun’s rising, it lights up. But what if you want it to do cool things? Like blink in a pattern? Then you add in an Intelligence Circuit, and if you are truly cool then you would use something like a Programmable Intelligence Circuit.
The Base (or in Cooking: Main Ingredient)
I had a hard time deciding between the PICAXE and Arduino platforms to start with. Both have major pro’s and con’s which have been rehashed over and over on countless sites, so I won’t do that here. I chose the Arduino Diecimila (Italian for 10,000th) over the PICAXE 28X1 starter kit for a number of reasons.
- The Arduino Programming Editor runs native on OS X, where as the PICAXE Editor only runs on Windows with Linux in the works, and as I am on a Mac, that makes it quite simple.
- The Programming Language for the PICAXE is a variant of Basic, whereas the Arduino Language is simple C/C++ so I can move on to software applications after awhile and not have much discomfort.
- Cheaper, in the end. My Arduino board cost me $32 where as the PICAXE board would be ~$38 PLUS another $26 (depending on where I went) for the USB cable. The Arduino board just has a USB port on it, which I can attach a standard USB cable to, much simpler in the end.
See? All in all it was a pretty easy choice for me. But if you want to do it too, then do what I did, research your options and make an informed decision. As I said their are pro’s and con’s for each system. One view can be seen here and another, here.
The Source (or in Cooking: The Sauce)
The Arduino Programming Editor is simple, clean and shiny!
Arduino Programming Editor
As you can see here, I have loaded the code for GuiBot’s Easy Arduino Robot from LMR. I don’t have a bot, so it’s useless to do anything, however I can study it and figure out what does what (within my hopes) and then when I get to actually program a bot I will have my feet wet already.
The Parts (or in Cooking: The Seasoning)
We all know that seasoning can make or break a dish, so getting the right parts for your bot is essential, or so it would seem. If your motors are don’t put out enough torque, your cool looking little robot probably isn’t going anywhere. So there are all sorts of things to understand (which I barely do even for a beginner) and know how to implement. So for now, I am following the time honored tradition of KiSS (Keep it Simple Stupid). When I get my board I am not going to start attaching motors and polymorph and sensors. I am going to first use some simple, good old LED’s. If I can get them to light up, hot damn. If I can’t, then why not? What am I doing wrong. Luckily, LED’s can be picked up pretty darn cheap (right around a buck fifty at Radio Shack) so if I screw up and burn one out, that’s life. After I feel comfortable with that, then I will be moving onto a Servo. I picked one up today at Hobby Town USA which suits my purposes just fine. It is a HiTec HS-311 Standard Servo. Cost me ten big ones. So if I blow it up, then no big deal, I can replace it fairly easily. This little bad boy (weighing in at a whopping 1.5 oz) has a torque output of 3.0kg-cm (42oz-in). Yeah, it can move 28 times its own weight, with ~5V of power being all it takes. Amazing. Operating speed? 0.19sec/60° AT 4.8Volt. Do I have any clue as to what this means? Hell no. But if I were to make a guess then what it means is that when the servo is being powered with 4.8Volts (based on this assumption I am going to further assume that that is the optimal operating voltage) it will make a 60° rotation in 0.19 seconds. I should find out.
The Chassis (or in Cooking: The Garnish)
Keep in mind that my correlations between robotics and cooking is based on my view of things. I feel that while the Chassis is instrumental in holding a robot together and allowing it to function, it serves the larger purpose of Physical Appearance, like the Garnish on a dish at a resteraunt. You want your Chassis (and by Chassis I extend beyond the typical definition and include the body into it) to reflect the nature of the robot. If it’s built for doing rough stuff, don’t build it out of toothpicks, but maybe you could use aluminum or another metal, and if it is a show bot (read: used primarily indoors to show your abilities) then I feel you should use a nice light weight hardwood (possibly stained to look purdy) or plexiglass/lexan to show it’s innards. If your soldering is horribly, I reccomend something a little more opaque, as it will still look good. When I get around to building my first few robots, I am not going to extend myself much further than simple, cheap materials.
The Tools (or in Cooking: The Tools)
So, now that we have most of the constituent parts (I probably forgot a few and mentioned only what I really truly have experience with) how do you put it all together? A cook/chef will use spatula’s, spoons, ladles, knives, pots, pans, and countless other cool things to do this. So what are the typical tools of the Robotics Hobbyist? Well that depends, everyone uses different things. If I had to make a list of what I consider to be the vital tools, it would be way different than everyone else’s. Sure some things like a Soldering Iron and “Measurey -Thingy” (Danish for Multimeter) would be on every ones list, but I feel some other things are necessary. So without further ado, here is my personal “must have tool list”.
- Multimeter
- Screwdriver Set (I like my stuff to have a multitude of functions for the space it takes up)
- Dremel Tool
- Hot Glue
- Epoxy
- Soldering Iron
- Computer (Be it running OS X, Windows, or Linux you might want one)
- Screws, Nuts, and Bolts (Depending on the permanancy of your project)
- Wrenches (Gotta tighten those bolts somehow)
- Creativity
- Beverage of Choice (some prefer Cape Cod, some prefer Stella, some Coors, me? I like Mountain Dew)
- Patience
Note that this list is subject to change as I actually start to figure out what the hell I am talking about. Since I haven’t built a bot yet, this is entirely specultation on my part based on observations of others work.
So I guess that’s it for today, I know I said I was going to inventory my tools, but this is incredibly more exciting for me, besides I spent all day scrubbing my grandfathers motor home, so I was in no mood for more monotonous work. Check back soon, since I will have my Diecimila around Saturday, so I will actually be having something worthwile to post. Tomorrow I think I will post my plans for an airsoft turret I will be making my mom eventually. That’s it for now, good bye.
