Liftoff (FW) build diary

[Liftoff]

I'll check him out, don't know what type of alloy he has though, its listed as grade EN485, but that's not a grade I ever heard of...
Chains and sprocket is a good idea, as you mentioned weight will be an issue, but its an other option.

Bumped into this website by chance, dont know if anyone ever bought something from them, it looks interesting, they even have a complete track drive system, and its not expensive at all...my only concern is its plastic!
http://www.vexrobotics.com/vex/produ.../276-2168.html

[Liftoff]

Small update:
Got the armour cut and it's now back from the shop.
The large plate is the flipper arm, the other plates are the front and side armour. I opted for the front and side armour to be cut in small parts mainly for two reasons...
firstly, the material came for free but in the form of small pieces from which I could cut just one item....
second reason is that if a part is damaged I could easily replace it.

Also received some various thickness of hdpe to which the armour will be bolted.
I think 4mm titanium and 20mm hdpe should protect well against spinners...at least I hope so!

Have ordered some aluminium plate and box section for the chassis...still waiting for their delivery...and then back again to the waterjet shop to cut everything to size.

I've had to scrap the previous machine and build a completely new one from scratch as the old chassis was simply too flexible to work with. The shape will still remain the same though, only the name will change. Might start a new thread later on when I start to work on it...

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[Eventorizon]

Are you going to be bringing the weight down so that you can come and play with us at the Champs :-) That would be awesome!

The main thing that stands out for me is using lots of small pieces to construct your armour. There will be more things that could potentially break and if something does go mid fight then you are going to be very vulnerable as more can be ripped off from the resultant hole left in the armour. (This is assuming they are not welded into one single piece.)

Have you successfully resolved your track issues as well?

[Liftoff]

Sure, now that I'm starting afresh it should be easier...and yes I'm hoping I'll be able to enter it in next year's Champs. This November I'm coming over to the Gloucester event, that will get me a bit familiar and hopefully meet some of you as well.

Regarding the armour, I really had no option as the material I had was not a full sheet. Thought about geting it welded, and in fact I might as well go on with it, the thickness might be a problem though but I'll ask around... btw its being mounted on 20mm hdpe, so even if a piece had to come off, it'll still have some protection.

The tracks should not be an issue now, the system is a simplified version of the previous one, now it will be totally encased making it impossible for the track to come off. Have a look at 6th post from top.

My main problem now is the lathe, have lots of parts that have to be machined and not having acces to one I'm seriously considering buying one...but that might take some time to happen!

[Liftoff]

Update:

So I just found out the local robot wars event will be held on the 10th November...perfect timing, the same day I booked for the Gloucester event! Tough luck! Will have to give the local event a miss...

Still, I have a robot to build and that will have to be built almost from scratch in 3 weeks! Looks like a mission impossible to me, but worth a try. My brother will take it to the fight if we manage to finish on time.

The tracks issue will hopefully be resolved with the latest (and final!) redesign. Machined again a set of wheels and rollers, and this time every thing will run on ball-bearings at both ends for better rigidity.
Yesterday had a new set of tracks custom ordered, I picked them up this morning...so far all is looking promising. This weekend will fit all parts together in the track holder and...fingers crossed!

Will post some photos later

Edit: Photos added

Drive is through the red wheel, will have to grind the motor shaft to 1/4"square. The middle roller is an eccentric tensioner. The other roller is the fwd idler.

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[Liftoff]

Good progress over these couple of days, built the first track module (sorry no photos yet) and most of the previous problems look like they're solved. To test it I coupled it to an electric drill as I still need to modify and mount the Gimson motor. It turns ok with minimal friction and the track stays put, one less problem to worry about.
Now I have to copy and paste to build the other module, and then the rest of the build...

[Liftoff]

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The assembled module less the drive motor.

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A view of the internals and a short vid clip in action.

[SamO]

"This video is unavailable"

[Liftoff]

Should be ok, now...took some time to process the youtube upload! The video shows how the interals look like, but in reality the belt and rollers will be mounted internally as shown in the first two pics.

[Liftoff]

The build is going on overdrive at the moment! Only have till Tuesday to finish it off and I really doubt I'll make it

So I got most of the structure finished, drive as well (still untested), Hdpe under armour almost ready, now I'll trim the base plate to size and screw everthing together. Next will be securing the pneumatics and then installing tbe flipper arm....still a mountain of work to do!

Progress so far:

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