New Robotics Website: www.amazingrobotics.com

Looks good, James.


That's a pretty nice building system.  I've been working with aluminum
angle stock lately, and making some progress, but it's pretty slow going
-- the T-slot extrusions and nylon connectors look much more pleasant.  
Also about 10X more expensive, of course, but I'm less sensitive to that
now than I used to be.  :)

The "Basic Cube Bot Kit" is a nicely configured kit: I like that I can
buy just the frame, wheels, and motors, and supply my own electronics.  
But it'd be helpful if you'd provide some stats on the motors,
especially how much current they draw under load.  I'd like to use my
own motor controller (a Pololu dual serial motor controller, or if
necessary, one such for each wheel), but without knowing the current
draw I can't tell whether that'll work.

Best,
- Joe

--
"Polywell" fusion -- an approach to nuclear fusion that might actually work.
Learn more and discuss via:  <http://www.strout.net/info/science/polywell/>

Joe:

I've been using 1/2" angle aluminum for my robot frames
these days.  Here's a picture of what my robot looks like:

   <http://www.mbbenson.net/Robotics/lab_odometry.htm#Robot%20Platform>

The aluminum is 1/2" aluminum that has been drilled out
with holes that are at the same pitch and diameter as
Lego brick studs.  While I used my CNC mill to drill the
holes, I'm pretty sure the same effect can be achieved with
small vice, a hand drill, and a Lego (tm) Technic (tm) brick
(i.e. the ones with holes in them) to use as a template.
Since my electronics modules also have holes along the
top and bottom at the same pitch and diameter, everything
just fits together.

A few weeks back you asked about shaft adapters.  If you look,
you can see my drilled out aluminum hex rod shaft adapters
as well.

The motors and shaft encoders are from Solutions Cubed:

   <http://www.solutions-cubed.com/>

Hopefully, you and others will find the links useful,

-Wayne

Neat -- sort of a do-it-yourself Erector set, but following the LEGO
standard hole size and spacing.  I like that a lot, because LEGO makes
some really useful robotics parts (e.g. gears, axles, couplers, and an
insane variety of wheels and tires).  Your approach allows one to
continue using those specialized parts, while building most of the robot
out of aluminum rather than ABS.  Nice.

You should consider selling those "RoboStruts".  I know, in theory we
could make them ourselves, but oi!  That's an awful lot of holes to
drill by hand, and if it's not done with precision, its utility is
greatly reduced.

Though I have to admit, I like the clean look of James's T-slot beams.


Quite so, thank you!

Best,
- Joe

--
"Polywell" fusion -- an approach to nuclear fusion that might actually work.
Learn more and discuss via:  <http://www.strout.net/info/science/polywell/>

Joe:

Exactly.  In addition, I get to use standard #10/24 screws, nuts,
and lock washers to bolt it all together and *it does not fall
apart*.  Many a Lego robot of mine has had its short life by
taking a dive off the table and onto the floor to automatically
disassemble itself.  No more!

The Vex stuff is pretty nice, but, it, too, is kind of pricey.


The last time I tried selling something to the robotics community,
I had a rather unpleasant experience.  I spent way more money then
I ever received back.  It is not something I would ever want to try
again.  I make far more money in a day as a consultant than I ever
made selling robotics products.  I have no objections to somebody
else taking the idea and running with it though.

What I have thought about doing is producing a metal jig with
the holes precisely spaced.  People would use the metal jig to
make their own struts.  They only have to drill the holes they
need on a particular strut.  Making few jigs and sending them
out to the various robotics clubs, is a thought.  The jigs could
be accurately reproduced at the club.  I really need to write up
an article and send it into Servo.

Sigh, so many projects and not enough time.  Double sigh.


Agreed, the 80/20 stuff sure does look nice.

-Wayne

Yeah.  Though with Technic construction, a LEGO bot can be pretty darn
tough too -- but probably not as touch as bolted aluminum.


Well, that's an understandable sentiment (followed by a generous one).  
I'm in a similar boat; I don't bother selling shareware any more because
it never, ever comes close to recovering the opportunity cost of the
time invested.  Easier to just give it away.  But then, that's what's
special about software -- once developed, you can give it away at no
further cost to yourself.  Robot parts, on the other hand, require time
and materials (plus tooling and skill) to duplicate.


That'd be cool.  I'm thinking about getting a drill press, so with a jig
like that, this might even be within my abilities at that point.  And
you're right, for a smoother look on a finished bot you could just drill
the holes you're using -- they'd still be at the proper spacing to fit
together with (say) Technic beams.


You and me both.  I don't even think I'm going to get the giant house
eyes up for Halloween this year -- it's just been a crazy month.


Out of curiosity, what does 80/20 refer to?  The composition of the
metal, or something related to its dimensions?

Thanks,
- Joe

--
"Polywell" fusion -- an approach to nuclear fusion that might actually work.
Learn more and discuss via:  <http://www.strout.net/info/science/polywell/>

I'm sure people would be willing to pay a reasonable price for the jigs.
"Teach a man to fish" and all that. Go for the Servo article!


Those 1/2 " angle beams look great! I'd love to find a decent source for
1/2" or maybe even 1/3" aluminum t-slot extrusions because I think that's
closer to the scale that most hobbyists would start experimenting with due
to cost and weight. Good work!

  I have a CNC milling machine with tons of bits...

  If anyone wants holes drilled, let me know.  I can do it for a small
charge.  I'm in
California (near Sacramento)

Rich

How big is your CNC mill work envelope?  My CNC mill work
envelop is kind of small (i.e. Sherline sized.)  I've wanted
a jig that is approximately 24" long, but my mill is not up
to the task.

-Wayne

Yep - I am very sensitive to the cost involved, myself. I  pretty much fell
in love with the 80/20 stuff from my Evolution Robotics ER1 kit that I got a
few years ago. But, as you have stated, they are sky high on many items.


Thanks Joe. That's a good comment on the motor specs - and one of the many
things that I had put on the back burner. The site alone, along with
sourcing parts, making sure the suppliers would be available, etc., has
taken me almost 1 year 5-7 days/week.

I'll try to get the motor specs on there ASAP. As a matter of fact, Dave
Peterson at www.newmicros.com  was kind enough to track down that info for
me a few months ago. They offer top quality stuff there, and their service
and assistance makes any price worth it!

Anyway, thanks for the feedback - exactly the kind of stuff I need !
Sincerely,
James C. Deen

James:

A most excellent addition to the robotics community.

What is interesting to me is that you started asking
questions on this list about 2/3 years ago and now you
are selling product.  Nice.

Congratulations.

-Wayne

Thanks Wayne!

2-3 years ago I was in the process of designing and building a robot for a
specific purpose. During that adventure, I ran into a couple of vendors that
provided what I considered to be less than helpful customer service for the
prices they charged. When I complained out loud that I thought I could do
better, friends and family said "Why don't you ?!". So, now my site now
exists. It has been a *lot* more difficult and involved than I ever expected
to get to even the modest point that I am presently at.

The people on this newsgroup have been absolutely essential in getting this
going. I offer my thanks to everyone that has ever replied to one of my
posts. One of my favorite things about this particular newsgroup is the
willingness of those "in the know" to assist those of us who aren't with
even the most basic of questions. I have to make an effort to resist posting
every little technical off-topic question I think of to this group because I
am sure I would get a valuable answer!

Anyway, thanks to yourself, and many, many others on here.

Thanks again !
JCDeen

That's a good point.  It makes for an interesting trade-off -- maybe
more likely to get stuck in a corner, but less likely to get stuck on a
lip.


Good point, and I dig that about it.  Two more suggestions:

1. Include a video of your cube-bot (with some additional electronics of
course) in action.  I'm curious how zippy those motors are, as well as
how noisy.

2. Tell us more about mounting our own motors and wheels with the T-Slot
system.  Say, for example, I want to do something funky like put an
omniwheel on the middle of each side, and I already have the motors,
wheels, and axles.  What would I need in terms of mounting hardware?

Thanks,
- Joe

--
"Polywell" fusion -- an approach to nuclear fusion that might actually work.
Learn more and discuss via:  <http://www.strout.net/info/science/polywell/>

Great suggestions! Hopefully these will be addressed on the web site in the
next few weeks - thanks ! I hope to have the Tutorials section built out to
the point that you'll be able to make a lot of things yourself with
off-the-shelf hardware, including specific sizes, etc.

I have one video of the CubeBot but it's pretty poor quality so I'll try to
have one up for viewing sometime this weekend.

Thanks again!
JCD