Chief Delphi - pic: 2003 TechnoKat Ball Drive : Patent Pending

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- - pic: 2003 TechnoKat Ball Drive : Patent Pending (http://www.chiefdelphi.com/forums/showthread.php?t=18772)

Quote:

Originally posted by Jeremy_Mc
You guys keep claiming that this will "inspire other teams". Perhaps to put the extra effort out and raise the bar, yes...but no more than your average joe team would, though.
Like I've said before, every bit counts in the long run

Personally, (not criticizing) but i think that takes away from the community. Patenting a drive train makes it a little awkward if a team makes a drive system somewhat similar, and then somehow it ends up they sue them over it or something. I'm not saying they would, but if they wouldn't, then why patent?
I'll let someone higher answer that one...

Odd thoughts yes...but I'm just curious as to why you would do that?
Please refer to previous answer...

And oh yes...an explanation of the system would be rather cool. I think I have it figured out but it's probably totally off.
You are comming to St Louis, come and see it for yourself

[edit] one more question, if someone were to pick that end of the robot up, would the balls fall out? or are they attached?[/edit]
They are attached

Quote:

Originally posted by M. Krass
It's no more susceptible to slipping than wheels interfacing with the carpet are.

You have the motors using a wheel to rotate the ball, interaction 1 that can slip. Then you have a slick ball that rotates on the ground, interaction 2. There are two of the main problem parts.

This is what FIRST is all about. I am Inspired. This thread is about Recognizing the Technocats. If you want, I will start another thread where I will recognize the things other teams have done that have inspired me and others like me. Not here. This thread is about 45's moment in the sun. I don't even care if it doesn't work as well as they would like. YOU MADE IT. You may never use it, but you made it. AWESOME. Every year there has been 1 team (sometimes 2) that has done something that really stood out. This year 1 team has done 2 things that stand out.
Thanks guys.

Quote:

Originally posted by JosephM
I never criticized the Tcats at all. I said I like it. I'm just saying that mabey the effort to build another bot or another drive system could have gone to inspiring another team.

even if another team had inspiration from them instead of them making a second bot (still don't see how they relate) they wouldn't have a moving robot if no one on the team knows how to make it move. i'm hoping the move-less robots will be elimintated this year, should be wtih that tranny FIRST gave every team this year

Quote:

Originally posted by JosephM
You have the motors using a wheel to rotate the ball, interaction 1 that can slip. Then you have a slick ball that rotates on the ground, interaction 2. There are two of the main problem parts.

There's slippage all over in a drivetrain. The cumulative amount is what's important. The number of places that slip, when examining things as a system, isn't terribly relevant.

I trust that the TechnoKats have worked out the perceived problems. But, we haven't seen it work at all yet. Like I said originally, maybe it's not really that big of an issue at all. Only time will tell.

I'm interested in learning how they solved whatever problems may have popped up, rather than making it sound like they made some horrible decision. It was their decision, not yours, after all.

team 461 would like to say one thing.
WOW!
that is all.

As always, I am inspired by what the TechnoKitties have done. Their ingenuity will push our team to do something as clever in the future.

About patents: They are intended to fully share an idea with anyone who wants to know about it. They do not stop anyone from using it. What a patent does do is protect the inventor from having his/her idea stolen. It stops a person or company from financially benefiting from another person's idea.

The original intention for the patent was to establish a record of innovative ideas in order to preserve them. It seems silly with today's technology, but if the only person on Earth who knew how to do this one brand new thing that everyone could benefit from died, that technology would be lost. The patent process helped prevent us from having to "reinvent the wheel" so to speak.

If the TK ball drive is patentable, then I say go for it. If a company sees value in their idea, then they can sell it and use the money for a greater good.

Great job 45.

-Paul

very cool design..and wow:yikes: great job t-kats

WOW!

Ideas don't drive technology advancement ... it's those who make ideas reality that drive it. Technokats, way to drive technology and thanks for letting us ride along!

Everyone, don't forget math class ... does anyone know the answer to the following equation?

Ball Drive + Segway =

... AWESOME!

I think some people are giving the TechnoKats less credit than they deserve...

Essentially, this is a true omnidirectional drivetrain. They can go forward, backward, left, and right at will. They can also change the direction their robot points at will. I haven't seen anything this great since the Kiwi Drive. Unfortuantely, you can't really do this without problems because of no 3rd drill motor this year.

With the exception of the Kiwi Drive last year, I've yet to see a team that has a truly omni-directional drivetrain. Now the TechnoKats are added to this 2 team list. Many teams can create the illusion of an omnidirectional drive but they really can only move in 2 directions in any given instant. Swerve drives have to wait for the wheels to re-align. Teams with a 2nd drivetrain that drops down still can't move in a diagonal path, and have to wait for the drivetrain to lower.

I suggest some people read this:

Quote:

Originally posted by patrickd

I think there is some confusion about drive systems... and locomotion in general.

On a plane (i.e. the surface of the playing field), describing an object's position at any instant in time requires three coordinates. For example, a robot can have an x-location, y-location, and direction (angle) which the robot is pointing. You can not describe the robot's position correctly with less than three coordinates. It is also possible to describe position with polar coordinates and other coordinate systems.

Now, over time, a robot can alter these coordinates. Typically, a robot can move forward and backwards. In other words, it can translate along one axis (move in the direction of the front of the robot). Most robots can also turn at the same time (adjust the angle which their robot is pointing). These two "degrees of freedom" are what you get out of a tank-drive system, which most teams choose to use. The number of degrees of freedom your robot has is defined as the number of coordinates (x-translation, y-translation, and z-rotation) that your robot can adjust simultaneously. A tank drive might be able to turn and translate in another direction, but it can not translate sideways, thus it does not have the third degree of freedom.

Typically, an omni-directional drive system is defined as a drive system with three degrees of freedom. Very few (I can only think of one last year) teams ever have three degrees of freedom. Tank drive only has two. In fact, even if you can turn all your wheels in any direction you like (i.e. swerve drive) you still have only two degrees of freedom, because at any instant in time your wheels are pointed in a given direction, and your robot is restricted to that linear and angular movement, giving you only two degrees of freedom. However, the advantage of the swerve is that you have the ability to change the direction of your prismatic (translational) degree of freedom with respect to your robot. If you can change wheel angles almost instantaneously, your robot is almost as good as one that can go accelerate in any direction at any angle, thus you virtually have three degrees of freedom. Robots that have a set of wheels that drop down perpendicular to your main set also only have two degrees of freedom, since at a given instant in time they can only move in one translational direction and rotate.

Now, a crab-walking robot could be built such that it has three degrees of freedom, but it would be difficult and almost certainly very very slow. The efficiency of an electric motor is far better than the efficiency of a crab-walking mechanism.

There only two mechanical ways I know of to get three degrees of freedom... meaning at any time, you can have any x-acceleration, any y-acceleration, and any angular acceleration. One of these I have posted a brief paper on how to get started on applying it to a FIRST robot (in the white papers) and the other is a little bit abstract and not too likely to work on a FIRST robot. One team had omnidirectional last year, and I forget the number, but I think it was a first or second year team. Basically it entails having three or four omniwheels perpendicular to the center of the robot. With three wheels, each unique combination of independent torques to the three wheels results in a unique direction and angular velocity of the robot.

Challenge for next year: Try to improve upon this drive such that the traction between the ball and the drive wheels can be improved to the point where it rivals a tank-drive robot. If anyone can do this, they would have the supreme advantage.

Unbelievable.. and I am not just talking about this awesome robot!

Quote:

Originally posted by Andy Baker
The balls are 8" steel "gazing balls" (hollow) that you can buy from a home deco store (we got them for $6 per ball at Homier.com). These balls have urethane molded over them at about a 1/4" thickness. They are about +/- 0.003" out of round. They dent if dropped, and weigh about 3-4 lbs each. They are not inflatable.

So if they dent when dropped what happens if you go up the ramp? Could the rows of dents be a problem eventually?

Quote:

Originally posted by Katy
So if they dent when dropped what happens if you go up the ramp? Could the rows of dents be a problem eventually?

I think he means dropped from a significant height. The 1/4" thick urethane coating, which he mentioned, would absorb any small forces acting on the balls.

Hmm i have played with an idea like that in my head before. Its kinda like the opposite of a mouse. What is the exact status of ur patent. Are u sure this hasn't already been patented. What type of patent are you applying for?

AWESOME WORK!!!

all i can say is...you had to wait until after i left didn't ya?? grr...