sabre

Finally decided on the name of my next featherweight and spent some time working on the CAD side of things.

For those that don't know I bought the frame and disc off kenny for the vert spinner he was building. Quick spec below,

- 3.6kg tool steel vertical disc, going at roughly 4500rpm
- powered by two brushless motors with a combined output of around 9hp (give or take)
- 10 cell lipos
- bosch 35s for drive
- full titanium chassis

Spent this evening reverse engineering the current frame and disc assembly into pro engineer allowing me to now go on and design the chassis and other parts into the design.

The disc is only 3.6kg? Wow, for some reason I thought Kenny had made it something mad like 5kg+
Not that being 1.4kg lighter is a bad thing, because it's still going to pack a punch.

Best of luck with the build Gary. Any idea if you're going to incorporate self-righting into it or do you intend to smash up the opposition before they get a chance to flip you? (or is that a silly question? :))

I remember this from the champs in Newcastle. Brilliantly engineered thing, going to definately pack a punch.

you should of said gary i have the cad's for it

No worries mate, I've never found drawings from other programs to easily import into pro engineer. Just you worry about sorting out that disc for me ;)

Been indirectly doing more work on the robot. For a uni project using ansys to carry out a finite element analysis I decided to carry out an analysis on sabre's disc. The following shows some of the pics of the results,

In each analysis the disc was completely fixed in the center, ie on a solid shaft and the disc was stopped from full speed to a stop within a 30 degree angle. Two rather large assumptions but they get me going on the analysis. Curiously if this was to happen the disc would experience forces of the order of 450kN plus. The first analysis was carried out with the force being applied to a tooth, ie me hitting someone else, and the second with a large force acting at the edge of the disc, ie someone hitting me.

Of course all of this creates these nice colourful pictures which is the bit that everyone's always interested in :D

Spent a bit more time on the CAD for sabre. Now that I have a job for the summer I should be able to afford to throw it all together and use these expensive parts that i've had sitting around for over a year!

Looks good - but get those sides slanted!! It will look so much nicer and be alot better against other spinners.

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Originally Posted by grant_ploughbot

Looks good - but get those sides slanted!! It will look so much nicer and be alot better against other spinners.

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I agree.

Everyones a critic! Lol but thanks for the advice guys, slanted sides it is :)

Looks good.

Any plans for self-righting? Or is the plan to destroy before you get flipped? :)

ahhhhh good old Ansys analysis !!

I remember that from uni... i did a whole robot arena, and got lots of pretty pictures !!!

Jamie yeah I'm looking at a self righter. Did the calcs and the disc is gonna apply an upwards force of around 30kg upwards at one wheel whilst giving the same into the ground on the other as I turn hard so I'm gonna need a big magnet, and a righter for when it all goes wrong :P

Jonno its still as wonderful as ever! No sodding undo button!!!!!!!!

ohhhhhhh yes remember now.

The first project i did on it was comparing the theoretical mathematical and ansys calculations of the forces of a car steering system under different conditions...

The amount of times i had to restart !!

You'd think they could add an undo button.

Spent a week working out the maths, and about a day working out the ansys, they actually matched.. well to the tolerance given. Computer wins hands down !!!

Was amusing a few weeks ago in the computer labs, around 40 PCs filled with us lot all working on ansys and every couple of minutes you would just hear large amounts of swearing along with a few mutterings of mesh, nodes or keypoints from a different direction :)

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Originally Posted by typhoon_driver

Spent a bit more time on the CAD for sabre. Now that I have a job for the summer I should be able to afford to throw it all together and use these expensive parts that i've had sitting around for over a year!

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Hey thats a pretty good CAD. What CAD system did you use :?:

pro engineer

I've used a lot of Cardboard Aided Design, and the last one a piece of string and wooden blocks. :)

Ah, Cardboard. Where would I be without you? The closest I come to CAD is Appleworks Drawing.

I don't even use cardboard :P it could be said that my robots aren't designed as such, they just happen to adopt a certain shape.