Regardless of your bite, half the energy of any collision comes back through the robot. Case in point being the magnets on my drive motors that were shattered in PP3D. You can thank newton for that one!
I'd still be weary of building it as a giant bearing. The tolerances are just too tight for it to take any kind of deformation.
So if it was instead done similar to mr speed squared, but use like 10x more bearings? With some kind of rubber on them to reduce the shock and hopefully stop them shattering. Also making the ring thicker vertically so it doesn't deform as much in that direction? Or using armox instead of hardox.
If you really want to go with the giant bearing idea, you will get better performance from a roller bearing than a ball bearing. I'd go for one large roller section and one ball bearing section to keep the inner & outer rings aligned.
Ok so taking your advice I have come up with 2 different ways to go.
A ball/roller bearing supported ring from 40x40mm hardox 26Kg
would probably use something similar to these: http://www.wychbearings.co.uk/nu205-e-tvp3-c3_nke.html
I think making it thicker with reduce the bending problem that mr speed squared had, although they only had 6 bearings per side.
bearing supported ring.png
Or my understanding of what overkill suggested, with a 26kg aluminium 6082T6 ring mounted with 18x18mm rollers and 25mm balls, which would then have hardox blades attached.
bearing with rollers.png
I am leaning towards the external bearings since they will be easy to replace and the ring will be stronger. Also seeing as it has already been tested on mr speed squared it should work, and its a lot easier to build as well.
I also seem to have managed to make them both 26kg completely by accident!
If you use external bearings, you can probably use smaller ones for the vertical support as most of the force will be in the horizontal plane. For the horizontal support bearings, you could use a stack of smaller bearings to save space and increase the load capacity.
The main problem with the external bearing option is that the vertical bearings will need to be protected from other spinners, while the taller integrated bearing ring is it's own armour.
What's your budget for all this?
That sounds reasonable for the bearings, so it would be a stack of say 4 ball bearings for the horizontal and 1 roller for the vertical. I don't really want to spend £1000 on just bearings especially if they are all going to break.
That's a nice looking robot maddox! I think a similar design as that but with 4x more bearing points would probably work good.
Budget is 2-4k might be able to get some stuff bought by the university though.
What do they mean in this when they say "sent to us by mentorn" did they provide parts?
Last edited by TechAUmNu; 27th August 2016 at 09:22. Reason: Phone typos
Mentorn / BBC gave each team a £1000 stipend to spend on parts only (no holidays to the caribean) but there's no guarantees the same will happen again for a second series.
Hehe, will be watching this with interest!
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