jorice@maths.tcd.ie (Jonathan Rice) (09/21/90)
In <7467@milton.u.washington.edu> zik@bruce.cs.monash.OZ.AU (Michael Saleeba) wr ites: >Does anyone know how polhemous (sp?) tracking devices work? ^^^^^^^^^ Polhemus Sorry, not really. I was told it was some sort of system using an AC magnetic field. >It seems to me that these devices are even >more impressive than datagloves; apparently being able to sense location, >direction, and rotation in three dimensions. Sure they can, but they can't measure finger positions (unless you put one on each joint, which is overkill). A position and orientation sensor such as the Polhemus is part of most gloves - VPL's Dataglove actually has a Polhemus sensor mounted to the back of it, while Mattel's PowerGlove uses an ultrasound ranging system. >Also, does anyone know who produces these devices commercially and how much >they cost? I don't have any price for the Polhemus, but I don't think you're talking cheap here. I do have some info on a full plug-in-and-go RS-232 position and orientation device from Ascension Technology Corp. of Vermont that uses a *DC* field. This apparently gives better immunity to eddy currents in metallic objects in the sensor's vicinity. Anyway, that device costs $5000. Not cheap. The beef: The Bird (TM) 6D graphics input device Ascension Technology Corp. P.O. Box 527, Burlington VT 05402 Tel: 802-655-7879 There's also this similar device called the Flying Mouse (TM): Flying Mouse (TM) SimGraphics Engineering Corp. 1137 Huntington Dr., Suite A-1, South Pasadena, CA 91030 Tel: 213-255-0900 Fax: 213-255-0987 I don't have a price for that. It uses a Polhemus sensor. -- Jonathan Jonathan Rice, jorice@cs.tcd.ie Disclaimer: I've no connection with Ascension or SimGraphics. I've a slender enough connection with anything in the real world, come to think of it.
murray@vs2.scri.fsu.edu (John Murray) (09/24/90)
In article <1990Sep21.143120.21614@maths.tcd.ie> jorice@maths.tcd.ie (Jonathan R ice) writes: > >In <7467@milton.u.washington.edu> zik@bruce.cs.monash.OZ.AU (Michael Saleeba) w r >ites: > >I don't have any price for the Polhemus, but I don't think you're talking >cheap here. I do have some info on a full plug-in-and-go RS-232 position and >orientation device from Ascension Technology Corp. of Vermont that uses a >*DC* field. This apparently gives better immunity to eddy currents in metallic >objects in the sensor's vicinity. Anyway, that device costs $5000. Not cheap. > >The beef: > The Bird (TM) 6D graphics input device > [..address + phone deleted..] I was told at SIGGRAPH that The Bird also uses a Polhemus sensor. On the other hand, the blurb I've got in front of me touts it as "the only 6D input system that works...near metal and other obstructions," so you may be right about the DC. (maybe Polhemus makes both, now?) Also, the $5000 price tag is the single-unit price. 2-4 units saves 20%, 75-99 saves 55%, >99 "consult Ascension." >There's also this similar device called the Flying Mouse (TM): > Flying Mouse (TM) > SimGraphics Engineering Corp. > [..address + phone deleted..] >I don't have a price for that. It uses a Polhemus sensor. The price I was given at SIGGRAPH was $4K, no specific mention of volume discounts. The Flying Mouse was being demoed in the Polhemus booth. In my (humble) opinion, one big difference between these two devices is ergonomic. Both are standard mouses on the ground, and 6D mouses in the air. (I'm pretty sure) both have RS-232 interfaces. The Flying Mouse is a largish thing, about like a DECStation mouse with wings that fit nicely under the thumb and pinky, while The Bird is a tiny thing that made my hand cramp just looking at it. Notice how everything using the Polhemus sensor has a pretty hefty price tag on it? My guess is that nobody gets the sensors for less than $1K or so. I'd like to know the single-unit price on it if anyone happens to know. SimGraphics had an engineering proto of a Flying Mouse with a hacked-up tactile sensing. Next year, maybe. Interesting, interesting... >-- Jonathan > >Jonathan Rice, jorice@cs.tcd.ie > >Disclaimer: I've no connection with Ascension or SimGraphics. I've a slender >enough connection with anything in the real world, come to think of it. John R. Murray | "They call me Mr. Know-it-all, I am so eloquent. murray@vs2.scri.fsu.edu | Perfection is my middle name! | ...and whatever rhymes with 'eloquent'." - Primus
pepke@SCRI1.SCRI.FSU.EDU (Eric Pepke) (09/24/90)
The Polhemus tracker is made, surprisingly enough, by Polhemus Navigation Sciences (which used to be Polhemus Data Services, I think.) Byte magazine had a little summary of the Polhemus tracker in the same issue that described the DataGlove, July 1990. The transmitter has three orthogonal coils of wire. So does the receiver. Each of the transmitter's three coils is pulsed, and you get amplitude measurements for each of the three reciever's coils, for nine measurements. That's enough. I think the tracker runs a couple of $K. Beacuse everybody uses their tracker, I guess they've got a pretty tight patent on it. Eric Pepke INTERNET: pepke@gw.scri.fsu.edu Supercomputer Computations Research Institute MFENET: pepke@fsu Florida State University SPAN: scri::pepke Tallahassee, FL 32306-4052 BITNET: pepke@fsu Disclaimer: My employers seldom even LISTEN to my opinions. Meta-disclaimer: Any society that needs disclaimers has too many lawyers.
cdshaw@cs.UAlberta.CA (Chris Shaw) (09/27/90)
In article <8073@milton.u.washington.edu> you write: >In article jorice@maths.tcd.ie (Jonathan Rice) writes: >>*DC* field. >> The Bird (TM) 6D graphics input device The Bird uses a continuous version of electromagnetic sensing (what someone refers to as DC field), whereas the Polhemus uses some sort of pulsed sensing. I don't know the electronic details. >I was told at SIGGRAPH that The Bird also uses a Polhemus sensor. No. The Bird uses Ascencion's "own" sensor technology. >other hand, the blurb I've got in front of me touts it as "the only 6D >input system that works...near metal and other obstructions," True. However, when I used it, it seemed to me that the cable was artificially too short, and that the effective range of the Bird was about 2.5 feet, less than Polhemus' 4-5 feet. Also, either the demo program introduced lots of lag or the Bird was heavily lagged. Either way, I think that the Bird's metal immunity is bought at the expense of limited range and slow response time. >(maybe Polhemus makes both, now?) No. Although there's a legal battle underway. The president of Ascension is an ex Polhemus employee. You can guess the stolen technology arguments. >Also, the $5000 price tag is the single-unit price. 2-4 units saves 20%, > 75-99 saves >55%, >99 "consult Ascension." The Ascension guy's dreaming. He's got to get his software up to snuff first. Anyway, do you plan on buying more than 4? >>There's also this similar device called the Flying Mouse (TM): > >In my (humble) opinion, one big difference between these two devices is >ergonomic. Both are standard mouses on the ground, and 6D mouses in the >air. (I'm pretty sure) both have RS-232 interfaces. The Flying Mouse is a >largish thing, about like a DECStation mouse with wings that fit nicely under >the thumb and pinky, while The Bird is a tiny thing that made my hand cramp >just looking at it. I thought that the mouse sizes were about equal, but the SimGraphics thing was better because it fit the right hand better (or worse, if you're left handed). >Notice how everything using the Polhemus sensor has a pretty hefty price >tag on it? My guess is that nobody gets the sensors for less than $1K or so. >I'd like to know the single-unit price on it if anyone happens to know. Basic Polhemus Isotrak is $3000. That's one source & one sensor. If you're going to use more than one sensor, get one of the multi-sensor single source models. It's a lot more convenient, and you have only one reference frame instead of N for N sensors. >SimGraphics had an engineering proto of a Flying Mouse with a hacked-up >tactile sensing. Next year, maybe. Interesting, interesting... Actually, it was another company who was doing the Flying Mouse hack with Sim Graphics' help. Anyway, I think that SimGraphics' software is a whole lot better than what Ascension is offering. Ascension is offering some doofus serial line driver software for PC's I think (like Polhemus with Isotraks), while SimGraphics has integrated its Flying Mouse into the Iris GL Graphics Library, and other machines also, I'm told. You can get Flying Mouse events in the GL event queue if you want. That alone (i.e. painless system integration with no kernel hacks) is almost worth the price of admission. >John R. Murray | "They call me Mr. Know-it-all, I am so eloquent. -- Chris Shaw University of Alberta cdshaw@cs.UAlberta.ca Now with new, minty Internet flavour! CatchPhrase: Bogus as HELL !
cdshaw@cs.ualberta.ca (Chris Shaw) (09/27/90)
>In article jorice@maths.tcd.ie (Jonathan Rice) writes: >>*DC* field. >> The Bird (TM) 6D graphics input device The Bird uses a continuous version of electromagnetic sensing (what someone refers to as DC field), whereas the Polhemus uses some sort of pulsed sensing. I don't know the electronic details. >I was told at SIGGRAPH that The Bird also uses a Polhemus sensor. No. The Bird uses Ascencion's "own" sensor technology. >other hand, the blurb I've got in front of me touts it as "the only 6D >input system that works...near metal and other obstructions," True. However, when I used it, it seemed to me that the cable was artificially too short, and that the effective range of the Bird was about 2.5 feet, less than Polhemus' 4-5 feet. Also, either the demo program introduced lots of lag or the Bird was heavily lagged. Either way, I think that the Bird's metal immunity is bought at the expense of limited range and slow response time. >(maybe Polhemus makes both, now?) No. Although there's a legal battle underway. The president of Ascension is an ex Polhemus employee. You can guess the stolen technology arguments. >Also, the $5000 price tag is the single-unit price. 2-4 units saves 20%, > 75-99 saves >55%, >99 "consult Ascension." The Ascension guy's dreaming. He's got to get his software up to snuff first. Anyway, do you plan on buying more than 4? >>There's also this similar device called the Flying Mouse (TM): > >In my (humble) opinion, one big difference between these two devices is >ergonomic. Both are standard mouses on the ground, and 6D mouses in the >air. (I'm pretty sure) both have RS-232 interfaces. The Flying Mouse is a >largish thing, about like a DECStation mouse with wings that fit nicely under >the thumb and pinky, while The Bird is a tiny thing that made my hand cramp >just looking at it. I thought that the mouse sizes were about equal, but the SimGraphics thing was better because it fit the right hand better (or worse, if you're left handed). >Notice how everything using the Polhemus sensor has a pretty hefty price >tag on it? My guess is that nobody gets the sensors for less than $1K or so. >I'd like to know the single-unit price on it if anyone happens to know. Basic Polhemus Isotrak is $3000. That's one source & one sensor. If you're going to use more than one sensor, get one of the multi-sensor single source models. It's a lot more convenient, and you have only one reference frame instead of N for N sensors. >SimGraphics had an engineering proto of a Flying Mouse with a hacked-up >tactile sensing. Next year, maybe. Interesting, interesting... Actually, it was another company who was doing the Flying Mouse hack with Sim Graphics' help. Anyway, I think that SimGraphics' software is a whole lot better than what Ascension is offering. Ascension is offering some doofus serial line driver software for PC's I think (like Polhemus with Isotraks), while SimGraphics has integrated its Flying Mouse into the Iris GL Graphics Library, and other machines also, I'm told. You can get Flying Mouse events in the GL event queue if you want. That alone (i.e. painless system integration with no kernel hacks) is almost worth the price of admission. >John R. Murray | "They call me Mr. Know-it-all, I am so eloquent. -- Chris Shaw University of Alberta cdshaw@cs.UAlberta.ca Now with new, minty Internet flavour! CatchPhrase: Bogus as HELL !