Not sure why it needs to be 20 MHz, but you should take a close look at the ATmega8 (16 MHz) - it's got 3 hardware PWM channels which should easily meet your output requirements and not load down the processor at all, leaving it free for other processing. I'm not sure what "AFAP" is. It's available in a 32 pin TQFP package so it can mounted on quite a small board and you would have plenty of I/O available as well as A/D converters, I2C, and lots of other peripheral capabilities. They only cost $3.75 each from Digikey (qty 100). A freely available (and very nice) C Compiler is available with Gnu's GCC which can be hosted on every major operating system like Windows, Linux, FreeBSD, NetBSD, etc, etc:
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Thus, your implementation would truly be open like you are wanting to make your design. Sounds to me like it fits nicely with your project goals. What could provide a better fit?
You are right. Airy seems to have a really low opinion of team-oriented workflows. I don't. I used to, to some extent, but, all you have to do --once-- is try to tackle a project that's bigger than you (no matter how good you are) to learn that lesson. Besides, who wants to be a loner?
Can you provide more details about these "Synthmuscle's"? What's the principle of operation? How are they built? How can a hobbyist or interested collaborator get one or build one? That's the first step, in my opinon. Validate the effector technology. Without this I don't think you have a project. Seriously.
I think the single most important component missing from the humanoid arsenal is a device that can be made to behave like a biological muscle. This doesn't just mean power/weight ratio, energy storage, efficiency, etc., but also things like having the ability to form it into many shapes and sizes as well as having the device conform to the operating environment. Not to mention such things as operating noise. A humanoid with hundreds of motors might be interesting, but, if I have to wear ear protectors while it's fetching me a cup of coffee it's a real deal-breaker.
To further explore the complexities of the picture you are painting...
While the little OVT7620 camera is neat, it is nowhere close to what is needed for the sort of humanoid you are talking about. The first issue is this insistance that some robotics folk have on using the seriously flawed television video standards for machine vision.
Everything about television (particularly cheap television, CMOS Barbie-cam's, etc.) goes against good imagers for robotics: spatial resolution, temporal resolution, interlaced scanning, CFA focal-plane imagers, dynamic range, crippled color space. Television standards (NTSC/PAL and their digital variants) are seriously deficient in ALL of the above listed areas. Clearly, using such cameras will not result in superior next-generation vision of any sort, 2D or 3D.
Yeah, but try to process higher resolution images in real time! I would be exstatic to be able to do real time stereo matching on a 128 X 128 black and white image!
Yeah, but I worked with SynthMuscles and I found them to be highly unstable. Their molecular breakdown due to quantum tunneling is a severe problem. I Synthmuscle is an inherently flawed technology.
I wonder if Mr. Bruce has solved the problem yet or if he is merely setting himself up for failure.
My point is that sometimes "Everything about television (particularly cheap television, CMOS Barbie-cam's, etc.) goes against good imagers for robotics" isn't necessarily true.
It's not enough to image using a camera; one must also process that video. High resolution can mean non-realtime processing.
I've put "inferior imaging technology" on a remote control vehicle and have been able to navigate just fine. That's because the human brain is able to process inferior images into meaningful information. The issue is that image processing technology is the more important thing than the imaging sensor in many cases. However, I agree that processing power is becoming more accessible.
Remember the context of this thread: Bruce is talking about a "next generation" humanoid project. That ain't gonna happen with a set of little CMOS Barbie-cams.
One of the things I do for a living is design real-time image processing hardware. 2K x 1K 60fps, 10bit RGB (30 bits total) high-dynamic-range (logarithmically encoded) images can be manipulated in real time in many ways. Powerful FPGA's make it possible. Not a problem. Time and money.
Ed, I often set myself up for failure, but you are making this way too complicated. The SynthMuscle, as Martin put it, is not a rubbery overly complex trying-to-memic-nature. It is a mechanical device that just needs some simple materials to make it work.
Martin, This is a simple device. I have been holding off details until I could get a decent sized group started (people are the hard part...you understand :o).
Bascially, the SynthMuscle is an electromechanical device. It uses two sets of coils (pinchers) to squeeze a kevlar ribbon (1/1000th of an inch thick, 1/2 inch wide) to generate friction. Two other large coils pull the ribbon being held by one set of pinchers to the other.
The distances are very tiny which enables it to work (fun with magnetic math). The actual pull distance is on average around 1/1000th of an inch.
The ribbon was the hard part. It is 200 kevlar filaments side-by-side bonded with a UV curable acrylic. In order for it to work, it had to be very thin, stretch less than 1%, be very strong, and wear resistant.
Anyone can make this thing. It is not elegant, but it does work. I will be posting the pictures, video, schematics, and notes on making one this week.
Alright, thanks for giving some information on it. You initiated this with claims of a new technology: synthmuscle. Your claim was that this was a revolutionary new technology that would replace motors and gears. This is a bold claim and bold claims require sufficient documentation to determine their legitimacy, documentation which you had not publicly provided on this newsgroup.
Because of your communication style, my first impression of this thread was that you were some kind of confidence man trying to reign-in suckers. If so, I was intent on stopping your little shinanigans by bringing up questions of the efficacy of the technology you claimed to have.
The challenge I made was necessary to try to establish the veracity of your claims and to steer away any suckers that a con-man might be able to milk for money.
However, since you have allowed me to peruse your yahoo group, I see that you actually have interesting ideas. I see that there is some legitimate claim to having a technology that might possibly replace motors. It is still in a rough state of development, but I think that the technology you have might be capable, with some development, of meeting the claims you make. On that basis, I wish you the best of luck in your endeavor.
There is nothing inherently wrong with CMOS Barbie-cams. There is nothing "Barbie-ish" about the technology residing in them. They provide great opportunities for cash-strapped robot experimeters. Showing the kind of disdain you do for them is not warranted with regard to hobbyists.
I too work on real-time image processing of the nature you describe.
However, remember the context of this thread: Bruce making wild claims about a revolutionary motor-replacing technology for which he had not provided any supporting information. As such, I thought he was a trolling confidence man and you seemed to be one of his sidekicks. It's easy to make false claims on the internet.
I've been doing newsgroups for over 10 years now and I have watched teams of trollers take over newsgroups several times. Their tactic is to set up an agenda and steer all conversations towards it. Their intent is always malicious and the results are the death of newsgroups by making real discussion impossible.
However, after examining his technology, I see that he has good ideas.
Keep in mind the fact that we can navigate quite well in a video game. The display suffers the same losses as cameras of the day, and we can also use cameras for remote navigation of a waldo. So at least you have some basis for experimenting, even though it will not result in human style vision.
I can't wait to see your pictures. But I can't help but wonder why you'd want to use coils (heavy) and magnetism (weak) instead of plates and electric fields. If new technology is being developed here, wouldn't it be more promising to explore the electric field as a purveyor of force, rather than magnetic?
You get me wrong my friend. I don't think there's anything wrong with CMOS/CCD "Barbie-cams". Especially not for the hobbyist. They are great, absolutely great. I have a dozen of them or so in different projects. Two of them are used in an eye-tracking goggle I designed for bio-feedback experiments. They are cheap, small, flexible. So, let's get that out of the way. However, you start talking advanced, next generation humanoid, advanced interaction with the environment and things are different. Using these imagers to try to develop higher-level solutions is a proverbial excercise in futility. A complete and utter waste of time. That's what I've been trying to say. Maybe this time I made it clear. I hope.
No, the context is the whole project. One for which absolutely no supporting data of any sort has been offered. Just wild claims. So, someone like me, who's done some pretty high-level motion control, image processing and related work, reads all of this and thinks "this guy is pulling our collective legs". So far, that's where my opinon sits. I think this whole thing is a joke. I might have some time this week to entertain looking at whatever might be in the Yahoo group. It bugs me though that it is OK to stirr things up in a public newsgroup and no information, absolutely no information at all is provided publicly to support these outlandish claims.
I think this is way out of line. How about we don't engage in name calling? I don't know this guy at all. I'm the one who voice strong skepticism about this whole thing being real. Read the thread.
Well, I've been doing newsgroups since before anyone knew the Internet existed. So what.
I realize that it is easy to loose sight that we might be talking to and with real people. I've taken the liberty to send you a private email with information on the company I own and run. I'm not this guy's sidekick, by far.
OK, how about some links? Or is everyone going to keep discussing this thing without one shread of evidence that any of it is real. I'll stand alone and say that what is being propose by Bruce is beyond the achievable today. And, that, based on the technology he is proposing the thing will not work and will provide any semblance of a useful humanoid. Humanoids are still way, way beyond what we can do in robotics.
Here's a simple test/task for Bruce and his team. Construct a wheeled robot (it doesn't have to be pretty) that can navigate any house and do just one thing: Use one or two arms (your choice) to make a cup of coffee and deliver it to the person who requested it. The environment, utencils and devices that this robot should use should be unaltered from those used by a human being. Make THAT happen and then worry about putting legs on the darn thing. This task alone could take a very capable team YEARS to resolve.
True, but this is only due to the superior cognitive abilities of humans. Sort of like driving in the fog. We can do it because we are able to process the seriously flawed information and get somethign out of it.
YOu have to keep in mind that a lot (years) of accumulated visual experience goes into being able to interpret flawed images. Something as simple as being able to tell that the shape behind a box isn't another object but rather the shadow cast by the sun requires pretty high levels of processing, particularly if done in real time, in motion and with all sorts of different objects (animals, plants, etc.)... Is that shape of a plane that's approaching me an object that's going to flatten me or just the shadow of an jet overhead?
I argue that you need lots more image data to even have a chance to derive real-world useful knowledge from a camera. I work with cameras costing in excess of $100K and, in some ways, they still lack what you need in advanced robotics (mostly frame rate and dynamic range).
The problem is that most people have never seen what a "real" camera looks like. Some of the better digital stil photography cameras can give you a sense. Dynamic range is not properly represented because you invariably endup in front of a 24bit (8 bit per channel) display. But, as a means for experimentation, someone could take their camcorder and a still camera and compare still images (you'd need video capture). The difference is huge.
So, if you were to put together a humanoid project, I would say that you'd need a team of a dozen accomplished experts JUST to develop vision technology that's conmesurate witht he stated goals. That will probably NOT cover the cognitive aspects of the problem. Just the hardware and some sort of processing engine.
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