the crypt

It's definitely quieter -- maybe more like a mortuary rather than a
crypt. But I have noticed the same slowdown in message traffic in most
other forums and groups, too.

Interest in robotics comes and goes. It tends to peak every 5-7 years.
We had a pretty good run in 1999 to about 2001 or 2002, but things have
gotten progressively slower since. I expect things to pick up again in a
year or two. However, much of this depends on the introduction of new
and interesting low-cost products for building bots -- microcontrollers,
sensors, whatever. A $75 vision system would get a lot of people back
into the game, for example.

I think there's also the matter of people adding certain posters to
their kill file. Not you but others. And it being the weekend, a weekend
of college bowl games, etc. (For that matter, don't even think about
getting many hits to the site next Sunday.)

I can say I didn't visit the sites because A) I've already visited your
sites (on numerous occasions), and B) PID math isn't much of an interest
of mine. But just to skew your logs I just visited all of the ones you
posted! <g>

-- Gordon

Gordon McComb wrote:


I think robots are of little interest because
essentially most of them don't do much considering
their high cost. They are just a fun application
for newbies in electronics and for engineers to
show off their know how.


--
JC

That might be true if there wasn't any recent interest, but that's not
the case. We're talking about how groups like this one aren't as busy as
they used to be.

Besides, the group was busier when robots were *more* expensive than
they are today. Under a certain threshhold cost is not a major
consideration, as long as there's something new. What's missing from
your theory is that there hasn't been anything radically new for a
while.

-- Gordon

Yes I was a bit off topic. I had something else
in mind. Sorry.

--
JC

Hi

JGCASEY wrote:

I read this and my first thought was "grrrrrr...
no!  wrong!  robots good! robots good!"

Then I started wondering if maybe you're right.
So that made me think, what exactly _can_ our
robots do?  Hmmmm.

I started to make a list of what hobbiests' experimental
autonomous mobile robots can do, now.  It's not so
easy. It has to be what they can really do, now. That's
what people see, that's what they are attracted to.

This is what I've come up with so far:

1. Maneuver.

        Move around without getting stuck or
        hitting things.

2. Navigate.

        Go somewhere.

        This would have to include everything like
        line following, odometery, wall following,
        GPS following, maze running, etc.

3. Acquire a target.

        candle flames, ir beacons, bright lights, orange
        traffic cones.  maybe this is also navigation?

4. Pick and place something.

        Grip or push things from one place to another.

5. Sumo.

        Seems like it needs a class to itself.
        Or is it just pick and place?

6. Soccer.

        likewise.  Or just team pick and place?


There are surely more but it seems like I can fit all the
things I've seen various hobby autonomous mobile robots
do in one of these categories. At least all I can think of at 2am.

But maybe this is really just 2 basic capabilities:

1. Navigate  (includes maneuver and acquire)

2. Pick and Place.  (includes sumo and soccer)

Is that right?  We've built a bunch of mobile pick and

best,
dpa

What do we do that is different? Are we a bunch of mobile
pick and place machines? The common riposte to the question
what is the use of xxx is, "What use is a newborn baby?"

One use they have that you left off your list is,

7. Entertainment.

They probably also act to inspire young engineers to
the future possibilities for automation.

--
JC

Boy, John, I'm glad you said that, because I think that is the very most
main reason we build robots. Either we find the building and development
entertaining, or we find watching the result entertaining. In the case
of Mini Sumo, I find both extremely pleasurable.

--
Randy M. Dumse
www.newmicros.com
Caution: Objects in mirror are more confused than they appear.

If we could get a robot to do something truly useful then the large
manufacturing companies, always looking for new markets, certainly
could. The more robotics becomes a commercial venture the less interest
there will be in hobbyists building them.

Why do people build and fly model airplanes? I don't imagine it's
because one day they want to build a larger airplane and fly in it; they
simply like to build things, they like the learning process, and they
like the challenge. They may also like the social aspect of meeting
other likeminded individuals, sharing ideas, and enterting contests.

Yet another valid purpose for robot building: Robotics is a unique blend
of disciplines that covers three major vocational areas: electronics,
programming, and mechanics. That makes it an ideal teaching tool whose
usefulness reaches far beyond what the machine actually does. As you've
found, kids are thrilled just watching these things move. It's the adult
that asks, "What does it do?" And if some little robot gets a kid to
take engineering or programming or electronics courses, who's to say the
little robot didn't have a useful purpose.

-- Gordon

I've been a software engineer ( or just plain programmer ) for over 20 years
now. Built a few robots that were 90% kit based. Just started building my
first one almost totally from scratch. So, I can really get into the
software, challenge of working on vision recognition, etc. The MOST fun I
have had recently working on the bot is ... drum roll ... cutting threads
into the aluminum extrusions with a cheap tapping kit I got from Sears! I
got the biggest kick out of doing that and then seeing the parts go together
into a fairly professional looking chassis ! For me, at the moment, it is
the building and creation of something that I just can not find elsewhere.
Later will come the satisfaction of seeing it perform the way I intended -
hopefully !

Just my 1.5 cents worth ...

JCD

What would you want in a vision system?  Do you have
a feature wishlist in mind?

My wife's cellphone has a 1.3 megapixel camera that
is about the size of the eraser on the end of a
pencil.  It can take still photos, and 30fps movies.

I would love to have one of those for a robot, but
1.3 Mpix x 30fps is a lot of data.  I think the
only way to deliver that much data would be to use
something like high-speed USB (480 Mbps).  Not
many microcontroller based robots are going to be
able to handle that.  The minimum system would be
maybe a mini-itx.

Intel has announced a new ARM Xscale processor, the
PXA271, that can interface directly to a CMOS camera.
It runs at 400MHz, has 32MB of RAM and 32MB of flash
on chip.  It should be able to run Linux with no
additional components other than a crystal.  It has
the integer XMM SIMD instructions, which should give
it enough power to do image processing tasks like
edge-detection.  It is clearly designed for PDAs and
cellphones, but it looks like it could be a dandy
robot controller with integrated vision.  I don't think it
is actually shipping yet, and I don't know what the
price will be.

Just delivering the data is not enough, to make a vision system, you gotta
do something with it as well. My robot is ITX based, and I have been
pondering a low-cost vision system for it.

1.3Mpix is pretty high, 1280x1024 pixels is a lot of processing, hell
640x480 is a lot of processing, I would be satisfied with 324x240 at 30fps
*and* be able to do something.

"mlw" wrote

Plain right. My first robot was (well, *is*, since I'm still working on it)
based on webcams that were capable of providing 640x480 at a decent frame
rate (I'm not sure, but I think it was 16fps) but we decided using 320x200.
Even though, because we are using only one mini-itx for everything, we can
only run very basic image processing algorithms (pre-processing, edge
detection, some frequency analysis, etc). We found that what kills us is not
the framerate nor the resolution of the image, but the quality of the image.
Because of its cheap construction, webcams don't offer or don't have the
capabilities to implement faster shutter speeds, therefore the images we
capture are sometimes blurred due to natural robot movement (off road
environment).

For the new robot (an ATV) we have a bigger budget, and we bought a pair of
professional firewire CCD cameras, with real lenses and shutter speed up to
1/100,000 of a sec. If conditions are right no matter how fast we are, we
always get a crispy image to work with. The fact that the lenses are capable
of f-1.0 is also a plus.

So, just to complement where mlw was going to, resolution and fps are seldom
the critical factors for computer vision.

Cheers

Padu

A vision system is not a camera. It needs to do image recognition, or at
least motion detection and simple blob counting or tracking. Examples of
commercially available self-contained units (at a reasonable price)
include the AVRCAM and the CMUcam.

For vision you can do a lot with fewer pixels. You don't need megapixel
imagers, but color can be useful.

There is no reason why there can't be a complete camera/lens/image
processing chipset for about $75. The CMUcam could be that price if they
made hundreds of thousands more of them. So, it's a matter of quantity,
and those quantities won't happen if the product is only for the amateur
robotics market. Those Sharp IR sensors are only afforable because the
"real" market is things like copiers and faucets in public bathrooms --
they sell hundreds of thousands of the sensors each year. They'd be
$50-70 bucks if they were made in low quantities.

-- Gordon


Bob wrote:

Thus you use what is mass produced, a PC, which most
people have. The cost then is in the radio interface.
The adventure is developing the software. It may be
beyond a hobbyist to develop new hardware but software
development only requires a creative brain :)

There is the commercial inspiration, Evolution
Robots, and back in 2001 LEGO Mindstorms Vision
Command based on a Logitech camera and its SDK.

The problem is hobbyists may have minimal programming
skills and PC products tend to be Microsoft orientated
requiring the purchasing of VC++.

My poor robotic base sits in the corner of the room
collecting dust waiting for me to develop a vision
system sufficient for its needs.




The main piece of hardware missing for a practical
robot is a sense of touch and sophisticated arms
and hands to do things.

--
John

Produce a PC the size of a pack of cigarettes, and for under $100
*complete*, THEN you have a form factor and price more people will be
interested in. The Mini_ITX is still too large. Bigger robots cost more
to build. While I have four PCs in my home, each weigh in excess of 15
pounds and need to be plugged into a wall outlet. None can be used for
robotics projects without gutting them. Certain people here would be
upset if I gutted their PC for my robot project.

My laptop is portable but cost $1,700. I use it for some robotics
things, but I'm not going to pay $1,700 for a dedicated robot
controller. Even a cheap laptop is $600+.

If you're looking to save money, you might as well pay $300 for a
self-contained vision system built on a small $100 robot. That's less
than a bare-bones IXT-based robot, without any sensors. If money isn't
an issue, then by all means the PC-based robot is a good direction. It
is not the answer to everything, however.


Oh? There are freebie libraries that have been available for years for
VB5 and VB6 for grabbing bitmap samples out of a Web cam. For .NET users
there's a great Sourceforge library that wraps DirectShow functions, No
C++ needed, ever. Microsoft still provides the .NET compiler for free,
and the 2005 Express versions of C# and VB are still either free, or
very cheap.

The Sourceforge project includes examples for grabbing bitmaps; from
there you can do lots of image processing without needing anything but
.NET. If you want to get fancy, there is sample FREE code on CodeProject
and elsewhere on how to write simple filters for edge detection,
pixillation, motion detection, and more. SERVO magazine recently ran a
series of articles on vision; the woman who wrote the articles provides
her code, compiled DLL and source, at no charge. You need only
rudimentary programming skills to call a couple of DLLs in VB.

I don't do Linux so I don't know what's available for it. But there are
PLENTY of accessible and FREE resources if you're developing for a
Microsoft OS, and C++ is not required. Some approaches are harder to
program than others, but wonderful things await those who make the
effort to better their knowledge.

-- Gordon

Something like this?

<http://www.gumstix.com/products.html>

but maybe that doesn't satisfy the "complete" requirement?

regards,
dpa

It doesn't have a USB port, which you need to use
most cameras.  A client USB port is available as an
add-on card, but you need a host port, not client.

Much serious image processing involves floating
point math, which the Gumstix doesn't do in HW.

The following non-x86 boards are NOT recommendations because I've never used
them, so you will need to do your own research to see if they are suitable,
but they both appear to have USB host:

http://www.embeddedarm.com/epc/ts7250-spec-h.html
    ARM based, US$149 according to the website. Complete ARM range at
    http://www.embeddedarm.com/epc/prod_SBC.htm  .

http://www.acmesystems.it/?id=4
    AXIS based, ImageCraft is listed as a US distributor, but I couldn't
    find it on the ImageCraft website. The UK distributor lists them at
    89.95 UKP excluding VAT (105.69 including VAT).

Simon.

--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
If Google's motto is "do no wrong", then how did we get Google Groups 2 ?

Truthfully Gumstix comes pretty close, at least on the size issue. Once
you get all the expansion boards for Ethernet etc. it's up to the $200
or so level, but it's still pretty good.

Funnily enough, it won't be robotics that will push smaller/cheaper
CPUs, but the growing trend to carputers. Right now it's a cottage
industry, but it's growing fast. Geek My Ride is becoming a huge
business. Rather than a market of tens of thousands (a *good* day for
robotics), it's a market of millions, just for the US. If just 10% of
the cars in California had a carputer, we're talking something like two
and a half million units.

All running off 12 volt DC, and all in a form-factor of no more than a
car radio.

-- Gordon