What is the name for this mechanical linkage?
Martin_H
Posts: 4,051
This linkage allows the joint to pivot like a ball joint, but it looks like half a universal joint:
http://hackedfrompieces.files.wordpress.com/2009/11/gelenk.jpg
Anyone know the name of it?
http://hackedfrompieces.files.wordpress.com/2009/11/gelenk.jpg
Anyone know the name of it?
Comments
The larger system is clever but I don't see anything in the close-up photo you provided that looks anything different than a plain ole "linkage". There's no "ball-joint" like behaviour that I can see possible there. On the other hand, what the servos provide and what you get with that linkage does add up to something interesting.
Unless the word you're looking for is "yoke".
ElectricAye, they do work like ball joints because there's another axis perpendicular to the larger one.
I see 1 DOF at the Y-shaped pieces and 1 DOF at the servo. Is there another DOF going on at the Y-shaped pieces I'm missing? When I think of a ball-joint, I think of something that has at least 2 DOF. Or are you talking about the ball-joint as the combination of the Y-shapes and servo?
Somewhere around here I have a dogbone link, a titanium rod with 2 spherical joints, one at each end. Big fun to fiddle with in your hand. Several of those in the augmentor/nozzle of the F100 jet engine in F-16 fighter aircraft, from my formative years at Pratt & Whitney.
Izzat really what it's called? You wouldn't just be jerking our chain, would you?
erco-bone, I believe.
The Chihuahua example is a dogbone because it can freely tilt his head from side to side.
Kind of like a seesaw.
A dogbone is a force ballancer free to move at the center.
Eye's example is ridgid so is not a dogbone.
Duane J
If you want to locate small quantities of other exotic, but sturdy robotic hardare... try DIY Ultralight suppliers.
http://www.qa1.net/qa1_motorsports/industrial/rod-ends.html
http://www.qa1.net/qa1_motorsports/industrial/rod-ends.html
http://onlinecatalog.leadingedgeairfoils.com/skin/entrymap/entrymap_singlebook.asp?SkinId=7.1.6.20
Yes that is a delta robot, and a search for dogbone link turned up pictures of similar sorts of mechanism. I can see why a spherical joint could be called a dogbone joint, but not the y joint.
If you watch the video the second degree of freedom at the Y shaped piece is more apparent. A delta robot requires 2 degrees of freedom at both ends of the linkage.
Martin, I'm sorry, but do you have a link to the video? I haven't been able to find it.
I appear to either be suffering from a false memory from watching too many home brew delta robot videos, or I can't find it either.
"Double Link Universal Joint" I believe is the correct name for this thing.
According to my reference book called "Mechanical Movements and Devices Originally published in 1911 - Algrove Publishing
Classic Reprint Series".
The vertical members in the photo are normally placed horizontally.
Now I know I will sleep better tonight!
For my money, one of the most awesome demonstrations of raw power is a military jet engine on full afterburner. The titanium nozzle flaps glow red hot, and the diamonds in the exhaust are supersonic shock waves. http://images.search.yahoo.com/images/view;_ylt=A2KJkPxKWiBRzCgAT4aJzbkF;_ylu=X3oDMTBlMTQ4cGxyBHNlYwNzcgRzbGsDaW1n?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3Djet%2Bengine%2Bshock%2Bdiamonds%26sado%3D1%26n%3D30%26ei%3Dutf-8%26fr%3Dyfp-t-701%26fr2%3Dsg-gac%26tab%3Dorganic%26ri%3D10&w=400&h=207&imgurl=static.ddmcdn.com%2Fgif%2Fez-rocket-5.jpg&rurl=http%3A%2F%2Fscience.howstuffworks.com%2Fez-rocket1.htm&size=9.5+KB&name=%2Falcohol+%3Cb%3Eengine%3C%2Fb%3E.+The+series+of+rings+in+the+plume+are+%3Cb%3Eshock+diamonds+%3C%2Fb%3E...&p=jet+engine+shock+diamonds&oid=490ee2922b46b3a2a1d53a1d9e19a720&fr2=sg-gac&fr=yfp-t-701&tt=%252Falcohol%2B%253Cb%253Eengine%253C%252Fb%253E.%2BThe%2Bseries%2Bof%2Brings%2Bin%2Bthe%2Bplume%2Bare%2B%253Cb%253Eshock%2Bdiamonds%2B%253C%252Fb%253E...&b=0&ni=72&no=10&ts=&tab=organic&sigr=11fmp6msb&sigb=147fodmb7&sigi=1151k3hfd&.crumb=CkRjVKV1f8X
Hey, man, hey, like.... double link universal? .... wow, man, wow.... hey, now we're gettin somewhere...
http://www.blacksmiths-australia.com/1907-Mechanical%20Movements,%20Powers%20and%20Devices.pdf
It looks like the other DOF is at the end of the tee.
Hello!
I'll second that. Watching a Fighting Falcon (F16) take off and zoom off like that is the ultimate display of raw speed.
But nothing tops the display of raw anything of watching a B52 Stratofortress taking off. But what fully tops that is a B36H Peacemaker taking off. Eight engines driving props going along and four burning, (they borrowed engine pods from the kludge that was the B47 Stratojet to augment the greatbird.)
Either of those two represent the great might and hope we represented to the free people of the world.
Anyway that is what you're device is.
I'm gonna stick my neck out and suggest a tethered rocket sled launch. The tethers hold it until the rockets get up to their maximum thrust before it's let loose, so you get to stand there and feel your various organs jostle around among your bones as the changing thrust frequency searches for the resonance of your brain upon its stem. And finds it.
Hello!
Then you were watching an F4 who was about to retire. By then they were on their last legs, the Falcons were beginning to take over at front-line (Actual AFB units, not ANG ones) and now even they are about the same age.
Some years ago I took a trip and saw a crowd of B52s standing around. I found out they were being stored at the Boneyard next to the big airbase in Tucson. At the museum next door they had four there, including a recently retired NB52 who's specialty was dropping experimental aircraft. Not surprisingly at the museum that was Castle AFB I saw one there who was wearing under one wing a first generation cruise missile.
"YouTube Videos"
This form replaces the rotary connection with a pair of ball jointed links.
Cool huh!!!
Duane J
Hexapods have essentially 6 legs where Canfield Joints have essentially 3 articulated legs.
BTW, the Canfield Joint basic patent #5,699,695 is in the public domain
The basic advantage for the Canfield Joint is it has more freedom of motion than the Hexapod.
Both require quite complex math for positioning.
Duane J