Pneumatics in ants

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snow-shifters
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Pneumatics in ants

Post by snow-shifters »

Since most of the forum is lost due to hackers, i thorght i would start a new topic for people to write about pneumatics.

-Has anyone got a diagram, i could have of a antweight pneumatic system
-does anyone know good suppliers or tips on flippers. :D
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Andrew_Hibberd
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Post by Andrew_Hibberd »

The basic diagram for a pneumatics system looks like this
Image


There are a few ways to build a pneumatics set for ants, firstly and the cheapest option is to convert a lego pneumatics set-although these are not as easy to find as they used to be. Also be aware that you will need two valves for this to work.

http://antweight.hostrobot.co.uk/pneumod.html

That is the link to the guide done by chris cummins, who used this system is his ant rebel. This is very simple to do and can be very effective. As far as i can remember the lego ram has about 1.5kg of force however this may be wrong.

The other way i know of is to use the inertia labs pneumatics from http://www.robotcombat.com , I currently have a built (sort of) flipper using this kit.
NB. The kit can run on 145psi but the antweight rules only allow 100psi. There are three types of valves avaliable on this site the first is the 5 way valve-it is used so that the ram can be forced both up and down and used a servo to control it [so plugs straight into the RX]

The second is the 3 way valve, this also plugs straight into the rx, the ram can be forced in one way either up or down but the ram would need some sort of return feature, such as an elastic band.

The third type is the cheapest option in theory, the hi through valve, however it uses a solanoid to control it so a voltage is applied and the air can pass. This will need a control board to apply the voltage-i am using a barrello ant 150 board (this also can control two drive motors as well). This valve will also need a elastic band to return it to the starting point.


Flipper design is not simple as the :
movement of the ram,
the distance the ram acts along the flipper arm and
the position of the pivot need to be taken into account.

I have tried to make the ram have at least 500g of force at the point of the flipper and
that the ram acts at 90 degrees to the line between the pivot and the point of the flipper arm.

Hope that helps a bit
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marksie
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Post by marksie »

I'm just waiting for my little tanks to arrive from robot combat, they send the middle size one by mistake, how are you lot pumping your one's up to 100 psi, i've used a CO2 bike pump but not sure what pressure i've put in :-? .
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Post by Andrew_Hibberd »

Currently i am just using a lego pump using the robotcombat connector-this generates about 50psi-but i will be going to get a bike pump with a gauage that goes up to 100psi.
I have tried looking at electric pumps but there doesn't seem to be an easy or cheap option avaliable.
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Adam Hargreaves
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Post by Adam Hargreaves »

You can buy Lego pneumatics from the lego site, u get a set with everything for ?20
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Simon Windisch
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Post by Simon Windisch »

Unfortunately lego item 5218 "TECHNIC Pneumatic Pack" is no longer for sale from Lego.

You can pick up a second hand kit from bricklink http://www.bricklink.com/search.asp?vie ... rt=P&sz=10
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Post by Adam Hargreaves »

shame.
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Post by snow-shifters »

at the moment im tryin to use a kinder egg as the air tank. but im having trouble keeping the air pressuree inside that egg. Any hints?
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Post by peterwaller »

You can use a small model aircraft fuel tank. It normally has three pipes coming through a rubber bung which forms an airtight seal. I blocked one pipe with solder as it wasn't required. The second you block with solder at the end that is inside the tank and drill a small hole in the side of the pipe about 15mm from the blocked end. If you then slide a piece of soft thin walled silicon fuel tube over the pipe it acts as a one way valve for pumping the tank up. The third pipe is connected to the pneumatic valve used to switch the air to the actuator. The tanks come in various shapes and sizes. You do have to allow for the fact that they do expand under pressure.
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Rhys
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Post by Rhys »

http://www.westons.com/acatalog/Online_ ... _3679.html

Good for about 10 flips at 100 psi. You can easy fit about 3 or 4 into an ant though.
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