Can't wait to see it in combat! The weight distro might bite you in the ass, but will have to see what 3kg of armour does to it _________________ https://www.halfdonethings.com/
Wed Nov 21, 2007 7:08 pm
Daniel Experienced Roboteer
Joined: 30 Aug 2005
Posts: 2729
Location: Gold Coast
Why does everyone pick on Avenger. You used it to test the first Hellcat and to test Devastator and Philip used it to test Marauder and now you used it again for Hellcat. It gets more air time during tests then it did in the arena. I brought home some 15kg steel blocks for a reason.
Thu Nov 22, 2007 8:38 am
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
Andrew, do you know the weight of the paintball ball valves that you have? _________________ So even the rain that falls isn't actually going to fill our dams and our river systems
Tue Dec 11, 2007 8:39 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
If you mean the 1/8" ball valves I am not sure. My 3kg scales a busted and my 700g jewelers scales are missing. I got them from Palmers Pursuit Pro Shop and they are listed as weighing 3.0oz or 85g which feels about right. they are rated to 1000psi. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Tue Dec 11, 2007 9:36 pm
assassin
Joined: 27 Jun 2004
Posts: 1105
Location: SunshineCoast
I'm going to try some different pneumatic setups next year Philip, and I have found some high pressure and high flow ball valves and fittings that are easy to get and are light and very good quality. But you have to pay thou. Also found some quick release fittings rated for 3000 psi which are about $15 - $25 each, which I like. PM me if that stuff interests you. _________________ Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.
Albert Einstein.
Tue Dec 11, 2007 10:27 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
Well its been a while but I have been busy.
Hellcat didn't go so well at our last meet. The key problems are:
Center of gravity is too close to the wheels so when accelerating forward the front lifts which makes it hard to get under other robots. This makes it hard to flip them.
The front of the flipper arm deformed slightly making it even harder to get under another robot.
The angle of the pneumatic ram is so low it requires too much force to start flipping. The arm would return too far making it hard to fire again. I had to up the pressure of the system so much I ended up bursting a seal in my low pressure valve.
So I will re-work the flipper to solve most of these in one go.
I have an old pancake type single acting ram I bought a couple of years ago that has been sitting on the shelf that fits perfectly in Hellcat. It has a much larger bore so will give me more force to play with. This arrangement will also allow me to switch to having the hinge at the back so Hellcat wont need to get so far under other robots to flip them.
I will also see about converting an old soda stream bottle into an accumulator to give a little more pop.
The added bonus is that after changing 2 fittings I can ditch the regulator. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Sun Apr 20, 2008 8:13 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
After getting a new $1.80 bushing today the new ram has been plumbed up minus a buffer tank. I was a little unsure how it would go at 200psi without a buffer but a 12kg lump of steel did a full 360 before coming back down so i think it should do ok.
Tomorrow I'll do up a mounting plate for the ram and reverse the hinge on the arm and then we should see how it'll go in practice. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Sat Apr 26, 2008 6:07 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
After some experimenting with valves and such Hellcat is looking good. Well as good as it can with various bits of scrap metal welded all over the place.
It is now using the ram and valve from the forward hinged setup but the ram is pulling chain which is connected to the rear of the flipper to raise it. The 5/3 dual pressure, centre pressurised valve was unpoppular because the only way to use it was to connect it up as a 5/2 valve. To make things easier I removed the solenoid and actuating piston from one side and replaced it with a chunk of ali and a spring and removed the centering spring from the other side. This works well.
At the moment it is being re-wired but has had some 3mm steel armour added to the front. the rest of the robot will be covered in something lighter.
I wish I had money for plane tickets. It looks like it will be flipper heaven in Sydney this weekend. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Sun Sep 07, 2008 10:11 pm
Daniel Experienced Roboteer
Joined: 30 Aug 2005
Posts: 2729
Location: Gold Coast
I went to the engineering market in Shenyang and got these.
The valve is 5/3 center pressurised with 1/2" ports and 12V solenoids = 105 RMB
The ram is 63mm x 100mm double acting with 1/2" ports = 95 RMB
Five 12mm push fittings = 2 RMB
1m of 12mm tubing = 5 RMB
All up it cost me about $44 back in Australia.
Just wished I got a few more fittings, but I got a little excited in that shop.
Oh, and a 3/4" 1000psi diaphrame valve was also only 100 RMB, or at the current exchange rate, about $20.
Here's a photo I took of the market. 100 stalls per floor and three floors high. Unfortuantly robot type motors were at the electronics market in a different part of the city.
http://www.facebook.com/photo.php?pid=1353632&id=763249842
Sat Jan 17, 2009 1:24 pm
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
quote:Originally posted by Daniel:
Oh, and a 3/4" 1000psi diaphrame valve was also only 100 RMB, or at the current exchange rate, about $20.
I am prepared to offer you $21.
Do you know if they have any 3/2 HP valves? I was looking to build that 3/2 Flow valve that Woody showed me. _________________ So even the rain that falls isn't actually going to fill our dams and our river systems
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