Here's a screen shot of Johnny Rico:
You can get the entire series in a 4-DVD set at Amazon.
Posted on 11/23/2007 8:34:39 AM PST by Flavius
Why, so I can spend more money on a car than I need to??
What happens when one of the multiple thousand lithium-ion cells goes bad, catches on fire, and/or blows up? That "does" happen, y'know. And what is the battery replacement cost when they inevitably go bad??
As I said, when they deliver a RELIABLE car that is capable of taking the place of a Honda Accord for a comparable price, call me. Otherwise, SDASU.
What is CGI?
True, hydraulic servo actuators consume about as much power in "throttling losses" (pressure drop) as actually delivered to the load. This all goes to temperature rise of the working fluid. I would judge that hydraulics is the only practical way to even attempt building a powered exoskeleton. I say that because of the power density possible with hydraulics. I can easily carry a two hundred horsepower hydraulic motor but I wouldn't want to put my hand on it when it's running!
Regards,
GtG
Here's a screen shot of Johnny Rico:
You can get the entire series in a 4-DVD set at Amazon.
Cool, thank you. I see it was originally produced by PAX. Too bad PAX essentially sold itself to NBC. They were more patriotic and religious than the other networks, or at least seemed like they could have been. I hope they will rerun it on the Sci Fi channel.
Reference
The TV series was quite entertaining, but it ultimately got canceled with only a few episodes to go. The story, as shown on TV, was therefore unfinished and everyone was left wondering how it was going to turn out. Later, the summaries of the (I think it was) three episodes were posted around the web so the fans would at least know what the writers intended, even if the shows themselves never aired.
It was a weekly show and the CGI artists were forced by scheduling difficulties to make the episodes pretty close to their air dates (and even so some of the shows were aired out of order). The commentaries on the DVD have lots of interesting information from the artists and directors. They would read the comments about the shows in the on-line forums and take that into account as they were making the later episodes.
Today the animation looks pretty simple, but back in 1999 it was considered pretty good for a weekly TV show. Clancy Brown reprised his role as Sergeant Zim from the movie.
The DVDs have the shows edited together to make a single long show out of what was (if I remember correctly) five shows. So you'll see "The Pluto Campaign", "The Hydora Campaign", "The Tophet Campaign", "The Zephyr Campaign", "The Klendathu Campaign", "The Homefront Campaign", each of which is an about 95 minute movie.
Because of the cancellation, "The Homefront Campaign" ends abruptly. There's been a petition going around the web trying to get the studio to finish it, but it's been so long I wouldn't think it'll get done. *Sigh*
Every once in a while I break out the DVDs and have a "Roughnecks" marathon session ...
ping
SDASU ???
You are really taking this discussion personally. I have not attacked you personally.
If you have a factory that can produce 1,000 a year, would you produce $100,000 cars or $20,000 cars the first year?
On Teslas web site they talk about battery life. They estimate that in 5 years (50,000 miles) the batteries will be down to 70% efficiency.
At the level of spending the new owners have obviously, a new battery after 5 years probably will not be a major investment. To you and I, it would, however.
I am glad they are getting these on the road so real world testing of it can proceed. I am sure it is not perfect, but they can learn a lot through owner feedback.
At any rate, I now realize that you have opinions that you will not change, so further discussion is pointless.
......Bob
At least with hydraulics they carry a large proportion of the waste heat back to the prime mover, where it can be extracted perhaps more efficiently than with the distributed dissipations of electrical actuators.
I bought a wheelchair for $500, and added batteries (another $200).
The seat has the joy stick on it, but other than that, it is all self contained in the lower portion.
The thought occurs to me, if I put a laptop on a platform, using wifi to connect the computer to the internet, some servos to control the joy stick and a tv camera with pan and tilt capabilities connected to the computer, I could sit at my computer, and send my little robot vehicle off into the real world.
Can you imagine my little fellow going to the store 3 miles away, picking items off the shelf, paying for it via the i-net, and bringing it home to me?
I think a few $$$ and some off the shelf items could make it work.
Am I way off base (he asks the engineer)?
....Bob
50cc engines or chain saw engines don't have enough power to get the job done. Consider, one horse power is 550 foot-pounds per second. OK, so lifting 550 pounds five feet in one second is a theoretical five horsepower. The actuator efficiency is about 90% overall, the pump is probably 80% volumetric and about the same mechanical. The servo valve is about 50% at best so we need: 5/(0.9 x 0.8 x 0.8 x 0.5) or 5/0.29 or 17.4 honest horsepower input to the shaft.
That's just using one actuator. If our suit is going to be moving it's other articulating joints, each will add to the required total. The hydraulic circuit will have one pump and dozens of actuators in parallel through servo valves. The function doing the most work will set the pressure generated at the pump and any other function will have to be throttled down to it's required pressure by it's servo valve.
You can save power by slowing down and allowing more time for each operation but that is not a plus for combat situations. Also consider that you are not going to sneak up on anyone with a full throttle go-cart engine strapped to your back!
Some of the newer battery technologies look good as well as fuel cells but in any event you are going to stand out like a search light to any infrared scanner.
Regards,
GtG
Weaker leg amputees could walk and dance.
Ah, yes---Tesla Motors, the new Microsoft. Sorry, but product testing is supposed to be COMPLETE before sales to the public.
"At any rate, I now realize that you have opinions that you will not change, so further discussion is pointless."
Unlike you, I actually looked at other sources than the company's website. If you bother to read some of the BUSINESS stories, you would see that even the head honcho of the company doesn't think the technology is a sure bet.
As I said, I'll wait on real data rather than speculation based solely on company propaganda.
How about a small turbine powering up hydraulics? Even a small 2 cycle engine could provide enough power.
That is essentially what the Military is doing with some of their small robot gun platforms. In truth you would not even need the joystick (on the chair), the power electronics to control the chair motors is currently off the shelf hardware and can be interfaced directly by model airplane RC controls. I'd be a little dubious about using the Internet for "real time" control of any remote vehicle as I don't know what response time could reasonably be expected of the control loop. You wouldn't want your "little guy" to run into a "dead spot" and wind up headlong in traffic!
The difference between your idea and the powered exoskeleton is a wheel chair does no (or very little) heavy lifting and thus requires relatively low power actuators. Direct electric drive is practical as are battery packs. The exoskeleton however is intended for "heavy lifting" which requires power. The highest power density available (horsepower per cubic foot) is hydraulic and so makes a powered exoskeleton possible. Notice "possible" is not necessarily practical. The actual source of power and cooling have yet to be addressed by the prototypes demonstrated. They do look promising however. GtG
actually, it is pretty heafty in the drive department. It was built to Medicare specs with a maximum 300 pound weight. at the max weight 55ah batteries will give it a 12 mile range, so who knows what the range would be without all the weight.
As far as the inet connection goes, Qwest has a broadband connection at 15mbs covering the entire town, so I don’t think it would be a problem for dead spots.
I am just playing with it anyway in my mind, but if I take any action I’ll forward the story to you, if you are interested.
.....Bob
No, that would be a theoretical 25 horsepower.
Naturally there would need to be a storage device of somekind to supplement power during periods of peak demand. Batteries or capacitors would suffice. In the case of a hydraulic system, some kind of pressure reservoir would do the trick.
But the human isn’t totally helpless. THe exoskeleton is only meant as a “helper”, not the sole source of muscle power. So lifting 550 pounds five feet in one second would only require 8/11ths of 25 horsepower, or 18 horsepower...assuming the human can do 150 lbs on his own without the exoskeleton.
But a hightech 50cc motor with turbocharger, fuel injection, etc, should give you minimum 6 horsepower. Very likely twice that. If you go to a wankel, or better yet, a turbine, then your power output to engine weight ratio goes even higher, but your fuel efficiency goes down.
As far as infrared goes...a human without an exoskeleton stands out like a search light.
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