It doesn't need large teeth with such a high rpm as even at full forward speed you are only going to get a mm tops engagement (can't be bothered doing the sum atm)
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It doesn't need large teeth with such a high rpm as even at full forward speed you are only going to get a mm tops engagement (can't be bothered doing the sum atm)
theres a reason for the small teeth Dave-
If you look at most drum robots with similar drums, the teeth tend to rip out of the keyways....my teeth go twice as deep into the drum as they protrude... giving it strength.
Also, if you look at the tips on a disc robot like 360... the teeth are 30mm on that... but only the last 5mm of that actually have any damage to them.
I reckon it'll be ok... might spin it up and drive it into diablo to see what happens when i get chance.
It should be plenty. You're spinning the drum at 215.2 revolutions per second, which means with two teeth, the potential for an impact every 1/430.4 or 0.0023 seconds. Even at a combined approach speed of 10m/s, you're getting 2.3cm of bite in absolutely optimal conditions.
Yeah drivings gonna be hard.... not even 1/4 throttle;
http://www.youtube.com/watch?v=E3AO3Arbo6s
That seems um... safe! :shock:
Like to see it at full speed :proud:
Not as bad as i thought it would be.
Up the armour to weigh it down and you will notice a difference. It may be worthwhile turning down the turning speed as well as chances are it won't need to be that high.
I'll need to have a look through my old uni notes as I once worked out how much upwards force i would have gotten with that tool steel disc at 4000rpm from a few basic sums.
turn it....down?.....How very dare you. :shock: :mrgreen:
That actually scares me, need too make sure this new one is angled very well and hope it will fly out when it hits :lol:
A low angle is no use against a ground skimming drum as I've shown many a time with the beauty machines which would beat many other spinner types on a regular basis.
Video to show all who doubt my engagement skills;
http://www.youtube.com/watch?v=2KoJjk--4wY
was a bit pants, hitting ploughbots old shell... about 3kg...not enough weight behind it to get a good hit on it.
everyone enjoys a good fail so heres 720's automatic disconnection setup after it KO's the opposition;
http://www.youtube.com/watch?v=NsdhS_vQZUg
But this is what it does to wood;
http://i685.photobucket.com/albums/v...s/651cf551.jpg
All in all not to bad... also made a start on the outer armour today which is coming along nicely.
that's given me a really good idea.
not to take my wood robot to the champs
What's the little black thing that rolls away before the Li-Po flings out? Is that a puff of dust or smoke as it hits the ground?
Looks pretty awesome though!
Just dust of the floor... and i think it was a castor that jumped out the box when the wood flew into it.
Haha, bet you worried for a moment though!
Didnt even notice until i watched the video back PJ...
Started armour, tacked in place... current weight is 13.515kg... should be in weight easy.
http://i685.photobucket.com/albums/v...s/af716551.jpg
Still need a name for it....maybe Gash or The Gash or i might just call it Boss.
Looks slick man, I love it! Do you intend to paint it or leave it shiny?
And, name? I like Boss. Maybe even Baws. ;D
duno might paint the hardox bits black and just sticker bomb the top or something - not seen that done on a robot yet.
yeah baws is ok- maybe honey badger... cos honey badgers dont care (youtube it if you dunno what im on about)
great name fits perfectly cant wait to see it chewing into other robots
Honey Badgers always go for the man parts, just thought you'd like to know that.....
lol already new, will have to attach some balls to the robot and see if it can get them :lol:
I both love that bot and am scared of it at the same time :lol:
looking good davindra and the robots not bad either, is that my hardox?
Yeah, i think you should just give me some more?
mr_turbulence, you made a great work, 720 looks great!
Which is the diameter of the shaft of the drum? what is the type of bearings that you using?
I'm anxious to can fight against 720 and Drumroll at same time =P
A drum-off! Will be awesome.
Thanks Guilherme, just finnished it today actually;
armour TIG welded;
http://i685.photobucket.com/albums/v...50898243D0.jpg
And painted;
http://i685.photobucket.com/albums/v...62C7C7956B.jpg
The shaft is 20mm solid silver steel, which is then key'd into each bulkhead 15mm deep (into 20mm bulkheads, and then bolted up with an M10 bolt either side... so, nice and strong hopefully.
these are the bearings im using; http://uk.rs-online.com/web/p/roller-bearings/0506208/
one either side, facing inwards... to try take horizontal impacts.
Can't wait to put Binky up against 720! Insane drum spinner against insane disc spinner!
Have you had a chance to test drive it yet? How fast can you have the drum spinning and still be able to drive it without it gyro-dancing?
Yes it would!Quote:
Originally Posted by PJ-27
Looking at your build diary Dave always feels me with a bizarre but equal measured emotion of amazement and depression, since I know there's a chance I'll have to fight it!
Thanks guys.
Not sure how well it'd do against other robots... it was desighned to fight hdpe/thin metal robots and nst mostly :) Would be good anyhow..
Any no, not had chance to test it...need to sort out radio reception problems before i do that... might have to mount a satelite reciever behind one of the wheels... turns out 2.4ghz has trouble getting through 20mm alumec :blush:
Any updates on your new drum robot or have you decided against it?
The drumbot idea got dropped after we bought the bulkheads and disc off Gary.
Binky is based on those rather than us trying to build a machine from scratch that could take the forces involved.
Might look at it further down the line but thats the same with the other dozen ideas I have got.
I'd try simply increasing the length of the aerial first.
2.4Ghz wave is up to 120mm long, so make the aerial longer and isolate from any metal, some thin plastic would help.
That's looking great Dave, as usual :)
I love how meaty those welds are, armour looks absolutely solid. I'm also impressed with how tight things are at the front of the robot. On Drumroll there is quite a lot of air and gaps around the drum/bulkheads that a horizontal nasty spinny thing could easily grab onto and rip apart, but you've managed to keep everything butted up against each other so much that it shouldn't be an issue.
Can't wait to meet it in the arena.
Thanks Jamie... was part of the design to get it all as small and beefy as possible.
just done an aggressive spin up test on a full lipo;
http://i685.photobucket.com/albums/v...720datalog.jpg
337.9amps, 13517rpm.... this is gona end in a fire :).... just goes to show how much more current you can pull through an automotive fuse then expected... bearing in mind theres a 100a fuse in there.
also its 390g over weight.... so ill probably change the baseplate for titanium, mill some pockets etc etc at some point.
this is going to be a beast, do some nice milling patternwise. it will look stunning
337 amps?
Man now that's just silly. :lol:
I will be expecting a phone call then.Quote:
Originally Posted by Gabe01
Given your self a job now Ed! I was just going to mill a square pocket in the back on the manual mill at the coopers, but since you offered... :lol:
I'm thinking of a circuit board design
Also cover the red bits in brown leather give it a steam punk look
Circuit boards exposed... Leather... I shoulda just built a terminator lol