Society of Robots - Robot Forum

General Misc => Misc => Topic started by: pflink on December 05, 2005, 08:42:46 AM

Title: recomendations for robotics kits
Post by: pflink on December 05, 2005, 08:42:46 AM

      Thanks for the sight, it has been very informative. I have been interested in robotics since I was a kid, but life circumstances has led me astray from my interetests.

      Anyhow, I have been looking into the Parallax Boebot at
Granted the price is a little steep here, Rat Shack currently has them for a roung 79$.

       I like the idea of an overall starter kit, not really looking to purchase the add ons and expansions. Figure I can use this as a starting point, and from there get into the more homebuilt areas.

       I have some understanding of programming and electronics, though by no means am expeirienced in either.

       Any thoughts/reviews/rants about this kit or others would be appreciated. Thanks.
Title: Re: recomendations for robotics kits
Post by: Admin on December 05, 2005, 09:12:25 AM
Hmmm I dont think I have actually ever used a robotics kit. But like 5 years ago when I was a freshmen in college my roomie had one of the original versions of the Boe-Bot. It was kinda neat, but I never actually tried it myself. And it was before I ever built a robot on my own . . .

But looking at it, it has a prototyping breadboard on it which is VERY useful if your a beginner and want to experiment. It operates on differential drive (the most basic and easy to understand of drive setups, consisting of 2 wheels and a castor). It uses PBASIC which is probably the easiest robot programming language ever to learn. Since it has a common BASIC stamp I would expect a lot of support out on the web about it.

I am not saying this is the best kit to buy because I have not looked into others, but it definatly looks good for a beginner who wants to experiment on it. Maybe a little pricy though, should look into other sites selling the same kit for lower prices.

What I like most about it is that it looks highly modifiable. You get a complete working system (which is the hard part) and then you can just add/remove components to learn about it. So yea I agree with you dont buy the add-ons, try to figure out how to make them on your own. You can probably convince me to write a tutorial on how to do something as well if you need it.

Hope this helps . . .
Title: Re: recomendations for robotics kits
Post by: pflink on December 06, 2005, 10:41:02 PM
I purchsed the Boebot kit got it from Radio Shack for 149$. Probably could have gotten it cheaper, but I'm impatient at times.

Kit comes packed in separate bags. Electronics, stamp module and controller board in antistatic bags, hardware and chassis were in plain baggies. Even comes with it's own screwdriver, but I was surprised it didn't have a grounding strap. It says to discharge with a grounded water pipe in the house, but I thought that was bad ju-ju with high end elecronics. Shrug.

The CD is packed with manuals, source and links. Even have manuals for the Parrallax Microcontroller kit, and another walking bot. Neat thing is I have source for all the addon packages here, not sure if that will help me design my own stuff later.

Only problem I had was connecting the serial cable, as this new comp doesn't have one . Had to run around town looking for one, apparantly their going out of style, and once again the style police forgot to inform me.

I have gotten the board together, and I just got to start playing with the servos. The bot should assembled and operations in a day or so.

The basicstamp2.5 language seems real simple to use, surprised I'm not coding line numbers with each entry.

I'll keep the forum updated on my progress, maybe it will help another newbie out.
Title: Re: recomendations for robotics kits
Post by: Admin on December 07, 2005, 08:38:21 AM
I have never used a grounding strap before . . . probably a good habit to get in to though. I usually just hold the ground and power pins together when I am fooling around with static sensitive stuff . . . but probably I am still taking risks . . .

Yea I remember the original BASIC language when I was a kid where you had to do all those annoying line numbers. PBASIC is like an improved version of it.

What sensors does the boebot come with? Photoresistors? I would highly recommend buying a Sharp IR Rangefinder. Its a really fun really easy sensor to use. Under $20 too.

Yea definatly post any interesting things you do with it.
Title: Re: recomendations for robotics kits
Post by: pflink on December 07, 2005, 11:00:00 PM
Kit comes with 2 photoresistors, an IR receiver and LED's and a setup for a couple of feeler sensors.
Have to say the manual/course is full of math overviews and exercises for the programming end of it.

Anyone know if Python can be used with Basicstamp 2? I plan on completing this kit, then running through the microcontroller manual, figure i can pick up any other components I might need. The board has 2 extra servo/motor control ports, so those will definitely be adapted to something.

From what I've been reading it seems like a normal hobby servo is like a stepper motor, in that it moves to a particular position and holds that position. Are these good for object manipulation?

Title: Re: recomendations for robotics kits
Post by: Admin on December 08, 2005, 08:05:50 AM
I guess servos can sorta be considered like a stepper in that it goes to a position and holds it . . . but it operates under entirely different principles. What you are really thinking is that it has position feedback control.

Unlike a stepper, a servo is a self contained feedback control device. To tell it to go to a position, literally just send it a square wave of a certain wave width. The width representing a certain angle.

You can also modify a servo so that it will rotate constantly and instead of having position control it would have speed control. The servo's on your Boe-Bot are already modified as such.

For manipulation, basic hobby servos are without question the easiest to use. But they arent perfectly accurate as they are usually off by 1-3 degrees.

What is Python?
Title: Re: recomendations for robotics kits
Post by: pflink on December 10, 2005, 01:01:15 AM
Hey my Boebot can beep now! I get busy at workon weekends so the project slows then. I had a couple of beers tonight, so blame Miller Brewing for any typographical errors.

    Python is a programming language that considered an open source equivelant to Visual Basic. I've been dabbling in programming for a few years, proceeding into variables, but have never gottin into arrays or memory management. Supposedly it is simpler to learn than C and is getting supported under Windows, MacOS, and definately Linux. It has been utilized in many areas that C is, including embedded systems.
     The question popped into my head as I wrote the last update, and I was in a rush/too damn lazy to search for the answer. Sorry. Here's the main URL anyhow.