Gravity 4

I'll start with the basic specs of Gravity 4: Drive; 2x 500 Watt wheelchair motors ran at 36 volt, driving a 12" wheelchair wheel through a 16:1 wheelchair gearbox. weapon; 63mm bore x 320 mm stroke full pressure Co2 flipper, fed by a 1/2" burkert valve, which is fed by a 2litre fullpressure buffertank,, and bungee return. Speedcontrollers are from mythras (dutch engineer), with the current limit set to 75 amps @ 36 volts. I use a multiplex 2010 transmitter, and a futaba dual conversion 8 channel receiver.

Ok guys, You've read the story, Gravity 3 worked pretty good, but pretty good is not good enough for me. So, enter Gravity 4 !... You'd think... But instead of making a bigger, better, bolder version, I sold Gravity 3 and built a cheep downgraded version of Gravity, jut to be able to go to 2 live-events in the UK ! I started with gathering all the stuff I had laying around. Decided to use what was left of the frame of Gravity 1, because that what give me some more time in building the rest of the robot. Added 2 nice wheelchair motors with the gearboxes attached, made a mounting platen and bolted them on. Put the old 63x320 mm full pressure ram in there, welded up a nice little flipper arm, welded a dirty battery box, gave the buffertank a place on the left side of the ram and the Co2 bottle on the right.

stacking up

remains of G1

Motormounts in

flipper arm on

more parts in

Pictures from left to right : Me working on the robot with my usual highly precision tools, mounting the mythras 75A speedcontrollers, connecting the high pressure pneumatic burkert valves and the hoses to the Co2 cbottle, and the gas-dump valve. In the fourth pic you can see how I just layout the pieces of box section, in a way that looks pretty straight :) In the last picture you can see those pieces of box section welded up, including the stainless steel plate on the front of the robot. The frame that has to carry the armour has been put up and welded, and the total package doesn't even look that bad now... Does it ?

good tools

filling her up

front view

front layout

and its welded

Well, it's almost done. NO, its not. Damnit, I have to leave for england in 8 hours, and it isn't even half done ! The first pic is the last picture I made in Holland, the second picture was made after I came back and took the robot apart again. The last pictures were made in Newark, with miss KitKar. I didn't have any welding gas left the night before I went to the UK, so my friend Alex (team ODT) gave me a hand with his electronic welder. He finished the welding of the flipper arm, and some more stuff. Now the robot was mechanically finished, but still no electronics... I threw everything in the car, took a shower and raced to Capelle aan de IJssel to join up with Marien and the gang to go to the boat. The trip was fine, we arrived at the camping site, had a few beers in the local country club (lol) and had a good sleep. The next day I finished the electronics on the camping site, and it was ready to fight at Liverpool !

no armour?


stripped too

nice... robot

bit of cellulite tho