Starting point?

I would like to build a robot with the following initial characteristics:
- walking robot
- laptop based
- having different sensors
Living in Boston I have been looking for robot clubs,
but was not successfull so far. It would be great if anybody could point me
to any existing.
Also if one can help me with pointing to projects that I could study as a
base for building mechanical and control system of robot... A lot of
questions including how much it could cost, how and where find motors, etc.
Thanks in advance.
Ek
Reply to
Eklmn
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May I suggeest something lighter than a laptop? Also, if this is your first robot project, I suggest building something smaller than rolls just to learn the basics.
The RoboBRiX Adventure set is nice for that. Lego Mindstorms is also very nice.
If you have your mind set on doing a larger robot at the start, then here are my suggestions:
I'd start with a Systronix JStik
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if I wanted a fairly powerful system, or a VIA Mini-ITX system if I really wanted a PC-class machine (running Linux, of course).
Walking robots tend to be extremely expensive. Unless you're very good you'll probably want a hexapod. You need at least two degrees of freedom per leg (two motors per leg). This gives you 12 motors. Supporting a laptop or a VIA Mini-ITX board takes a bit of power, so this will be fairly heavy.
I would estimate that you might be able to get motors for $50 to $300, depending on how good you are at this sort of thing.
For example, look at Lynxmotion: their rolling robots are *much* cheaper than their walkers. Their high-end walker goes for over $1000 with upgraded motors and it is too small for what you want.
I'm thinking (in the future) of building something based on the Shelob legs
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Each leg has four motors. I want to scale this up so that it would be a hexapod or octopod with a 12"-18" center. I estimate that motors would average $200, which would mean (for an octopod) spending $6,000+ just on motors alone.
Whereas my next big project (Harvey) is based on wheelchair motors and will hopefully be able to climb stairs will have a total hardware cost of less than $1,000. --
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Jay Newman
Reply to
D. Jay Newman
Thanks, Jay,
this is a great starting point for me. I was thinking to use laptop for robot's brain to avoid using wires between robot and main computer. My intention was to use wireless network between them. Let me look at your suggestions/links. Are there any projects that use non-PC computers for robots with wireless network?
It was in my pasture when I programmed PIC controllers and made electronics boards, but now I am kind of lazy, please do not understand me wrong, and would like to concentrate on programming robot behavior rather than doing mostly mechanical and electrical work. I am thinking to find a prototype of a robot or parts that can be reproduced quicker and then do more programming. For that I may need to see what other people done. I hope that somebody will respond and send me a link to local (Boston or close) robotics club or group if such exist.
Another reason for laptop was that multimedia devices could be just plugged in without writing any code. I need to learn how non-PC based systems would read and process multimedia.
Yes, hexapod looks really right thing for me now. So my plan is start looking around - hexapod mechanics - estimate how big it should be in terms of size, weight and cost - look for robot's brain: laptop or something else.
Thanks, Ek
characteristics:
Reply to
Ek
Hexapods are fun.
Processing multimedia on a non PC platform will present a challenge.
Putting a physical laptop on a Lynxmotion hexapod will probably not be possible. Consider bluetooth.
If you look at the EH3-R, you will find a neat platform. I enjoyed building it greatly, and programming it was fun. I "let my code free" into the wild, and presently it is being improved upon by others.
Mine is at
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For PC based robotics, people are looking into things like the mini-itx and PC-104 style platforms. This still leaves you needing some sort of I/O capability, which people generally fill with a microcontroller.
Mike
Reply to
blueeyedpop
Whats going to interface with the sensors on the robot ? How are you going to hook them to a pc ?
for some kits including a walking bot have a look at www.lynxmotion very nice easy to build kits. The hardest thing is peeling the cover of the lexan.
For an easy to use board talk a look at
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I've used a few of Brians boards for various projects and work. Uses the atmel atmega128 For windows can download avrstudio from atmel and winavr (gcc port) from avrfreaks.com
For higher powered boards
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Depending on what you need to do have a choice between dsp based (pod products) or philips arm7 based(arm products)
Choice of forth , isopod , c or asm for both pod and arm products.
Quite a few others make small arm based boards. arm7 is a 32 bit micro, quite a few companies make different varieties of it.
If you really want to use a motherboard look at the via mini-itx motherboards 17x17cm or wait a bit until the via nano itx boards are avilable 12cmx12cm
Even then your going to need something like one of the servopod or isopods or something similar for io.
If you plan on using lots of sensors you may want to offload the reading and direct control to a small micro mounted next to it then communicate via can or i2c / spi depending on the number of sensors to the main controller.Less processing work for the main controller.
Can get some cheap pre-assembled boards from
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for microcontrollers like pic, avr, 8051 etc
Alex
Reply to
Alex Gibson
Might help if I get the link right
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Forgot to say you can use these with c , basic or asm Brians got some example programs on his website.
avrfreaks
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has lots of projects and information on avr's
some projects that can be done with avr's
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Alex
Reply to
Alex Gibson
Is futurelec.com for real? Their PCB prices are very low. However, I was concerned when I saw that their DC motors were "coming soon" in August 2003.
BRW
Reply to
Bennet Williams
Hi Ek, as others have mentioned, building walkers tends to have a steeper learning curve, plus involve a lot more expense, that wheeled bots. I've been working on and off on mine for a couple of years so far. Controlling 12-16 servos and/or motors on legs is a lot more work than 2 motors on a wheeled bot. The other really big problem is that a good-sized walker will have trouble lifting and carrying around its own batteries, let alone a notebook computer. The bigger the walker, the heavier the motors, gearing, and batteries need to be.
If you want to take a look at a lot of existing walkers, I have a pile of links. The walking machine catalogs are a good place to start:
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AFAIAC, Rbt Full at Berkeley is the best single source for info on walking bugs+bots. Also, a lot of people find my projects page on walking of interest.
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have fun, - dan michaels ===================
Reply to
dan michaels
I've never used them for pcbs but have quite a few of their pic and avr boards. Good for cheap quick oneoff projects. Some of the cheapest dev boards you will find.
Can take up to four weeks depending if they have stock or not. I've had good service from them.
Seen a few comments on their pcbs
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Seem to be a mixed bag on the pcb service.
Alex
Reply to
Alex Gibson
In Nashua, NH:
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At least an hour from Boston, depending on traffic.
--Jay
Reply to
Jay Francis
Thanks everybody for a lot of information. It will take some time to consume it :-)
Ek.
Reply to
Ek

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