Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
mmm well i really am busting to build a working little bot, but just cant get any ideas for one.
the crusher is what i really wanted but that drill is just too huge for such a purpose. would be great for a featherweight lifter though (ideas ideas ). what im proposing to do is actually put a hydraulic system into the the beetle. albiet a totally gutless hydraulic system but hey it will be different.
ive got a couple of little bits and pieces ive accumulated over time that will make a fun little system. ive used some syringes and some water at the moment and using a 12g/mm (or some such stupid scale) and 6g/mm one i can send my 5kg scales off the dial. before the piston rockets out and blasts water everywhere hehe.
the thought is to use one of those tiny water pumps from dse but i want to see if i can modify it to be powered from the 550 and timing belt system. that will really build up somewhat of a pressure. i also have some impellors from old hyrdoponics pumps that i might put to use if that idea falls through. heres some of those pumps.
ive seen a little hyrdaulic ant that used cooking oil or something as fluid so ill pinch his idea
as for the piston... mmmm i was going to use that syringe but not sure anymore on that. i compressed both the syringes at the same time in the vice and the interconnecting pipe shot out across my lawn hehe, i guess it was 40psi or so? only needs to be one way i guess. the plan is to reverse the pump and suck the fluid out. not worried about air in the system as it seems to have a shyte load of grab with it in their anyway lmao.
no doubt it will be far less powerful than an electric system but hey how can you beat the coolness of hydraulics in a little bot... (think ill call this one, hyrdo.. i like that name for some reason) _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Sat Aug 20, 2005 10:25 pm
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
A positive displacement or piston pump would give you better pressure than a centripetal pump.
Two meter head of pressure is 2.8 psi. I wonder how a 12 v car tyre compressor would go pumping fluid. _________________ So even the rain that falls isn't actually going to fill our dams and our river systems
Sun Aug 21, 2005 6:22 am
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
it would be interesting to get one of those working as a hyrdaulic pump, might give that a go when i work out the cylinder _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Sun Aug 21, 2005 8:40 am
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
A cyclinder from car brakes might be modifieable to suit. _________________ So even the rain that falls isn't actually going to fill our dams and our river systems
Sun Aug 21, 2005 12:35 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Brake cyclinders don't have much travel and (according to my friendly machanic) they often don't have limit stops, so the piston can pop out the end if you ar not careful. They also weigh quite a bit.
I can't see hydraulics being effective in a beetle - the original crusher was pretty good, so why not down-size it a bit to fit into the weight? You could use a slightly smaller motor and change the jaw geometry to give a bigger leverage reduction and thereby keep the same crushing force. There is always that Ti sheet you could make jaws from... _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Aug 21, 2005 12:58 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
brake cylinders would probably be huge and of cast iron i would think.
the drill just cannot go in the beetle, its 600g alone and then i need a huge power source to power it. i was thinking of removing the case and just clamping the ring gear in for mounting but even then barely any weight is removed. only way i could see it working was if i where to make a custom gearbox and that seems to be really hard with only plastic gears around.
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
played around with the crusher again today, i tried to change it so the drill was facing straight upwards pulling the arm down which is a far better setup.
no bending of the drive shaft this time and it definitely had the power, it was kinking 6mm polycarb very nicely,but no way i could get it setup like that in a beetleweight. it was about 2x as tall as the featherweight lol. i took a look at the crusher jaw on sir killalot (some old style robot wars there) and that has an interesting design to it where the actuator lays flat across the robot and pushes against a linkage which closes the jaw. may have a look at that.
bah?!, beetleweights are annoying me now... got all the parts and just not any idea how i want to piece them all together. now i remember why ive never finished one of these things lol, so many ideas to try _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Wed Aug 24, 2005 9:59 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
felt the spirit of ghetto robotics today so i got some old pieces of 3mm aluminium and a couple of motors and hunks of steel and built me a crapsled tester for the drill motor and belt drive.
it is hands down the most shameful piece of work youve ever seen and thankfully ive disassembled it but i got it spinning by divine miracle and the belt drive is great, never slipped and instant spinup onto the 300g bar. spin up was maybe 1 second tops and the ratio is about 2:1 so im guessing about 4000rpm. there was so much slack and slop in the system im surprised it spun at all... no bearings or anything just the shafts running in some holes i drilled, ghetto!
it all came to end when one of the spacing pipes fell into the spinning bar and the entire piece of 4mm threaded rod holding it together was bent into a big ole V shape...
im tempted to re-assemble the old spinner beta max and stick the decent belt and drill onto it now.... or just make a new one with a decently made and designed spinner system. i was thinking of just using a stationary axle this time but finding a 4mm ID bearing would suck quite a large amount. _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Sat Aug 27, 2005 4:42 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Why such a small 4mm axle? Go to an 8mm axle and use some cheap bronze bearings like these:
http://www.flocast.com.au/brz_bushes_mtr%201of2.html
. Flocast bearings are available at Edcon steel near you and you could use a cut down high tensile M8 bolt for the axle _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sat Aug 27, 2005 7:04 pm
andrew
Joined: 16 Jun 2004
Posts: 3110
Location: Castle Hill, Sydney. N.S.W
or another method is to get small bearings from a scooter wheel (those razor type things) and use a threaded rod through it
thats what im oding and im sure it wont bend or break. _________________ Andrew Welch, Team Unconventional Robotics
Sat Aug 27, 2005 7:31 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
the 4mm seems to stand up surprisingly well, im sure its a good grade of steel too as its very tough to file although ive bent the crap out of it trying to remove it from the old bar (super glues second victim...), that was more a test to see the robustness and power of that drill and belt combo, gets my thumbs up! and ill also have to try find some old printers now
8mm diameter seems like an unneccesarily huge diameter though dont you think? i reckon you could bore it out quite a lot actually and still have it work well enough.
im fairly sure i wont have another spinner again in this class though. all of mine seem to be quite frankly, shyte house this crusher will get built!
btw heres a video.. just trying this bodgy medium so ill see if works myself...
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
ah well, nicks one is getting close to being done so i better make it some fodder,
cant be assed making up a weapon for it anymore so ill just make it into a cobra type wedge bot. with the slow and steady cybot drives, 7.2v nicads and the IR controller. should be done within a day. _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Wed Aug 31, 2005 8:46 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
okay the wedge is all layed out, but i had a major flash of inspiration (also known as one of my trademark plagurisms from some other design ) whilst looking over the can opener website
i figured that by having a horizontal crusher i might just be able to cram everything into the weight limit. and by having the little "jack" bolted to the robot itself and having the drill itself move back and forth along the robot i can make the mounts very small and also double as the jaw linkages.
im still cadding it up but its looking quite good at the moment. and having the drill pull the jaws shut in that sort of setup should mean its giving all its power to crushing, as opposed to last time that sort of pulled the jaws shut at a wierd angle.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum