Newbie with a question

[Will]

Hi All!

I'm Will and new to this but I've been interested in building robots for years (I just had too many other things to do!) but I'm now at a point where I wanted to get involved in making something.

I've seen the general advice to newbies already - build small (lightweight seems to be the ideal category as a starter) and read the build threads etc which I will do as questions occur to me.

I've got a few ideas (but don't we all!) involving springs to store energy vs CO2 or other methods as I could see them being much lighter weight than CO2 in the smaller weight classes yet still give a very explosive force on release and be much cheaper to maintain. I note in the rules that they must be unloaded at the start of a fight which seems perfectly sensible for safety. Has anyone used these with any success? Or is it in the realm of half baked ideas that don't quite work in practice?

I'm in the northwest (St Helens) so if anyone is nearby I would appreciate seeign them in the metal/plastic/etc to get a feel for things in the metal; I'm even prepared to lend a pair of hands if anyone needs them as I appreciate getting hands on is the best way to learn and don't mind being a spare wheel in a team.

[Eventorizon]

Hi Will

As you saw, the best place to start is the Build Diaries and reading through the posts in the corresponding weight class. There is no point in building a Lightweight in the UK though as no one has an arena to run them. The most common starter classes in the UK are Featherweight, Beetleweight and Antweight, and once you get there you can build a Heavyweight.

Springs have been used in the past but not recently. They will pack less of a punch than pneumatic weapons but I can see them still having enough power to flip opponents or even toss them out the arena. It would be great to see a spring based flipper! You would also have the advantage of, pretty much, unlimited flips, where as a pneumatic robot probably has a max of ~25 flips in a fight (That is a total guess, but its limited regardless)

There are teams based in Leeds, Sheffield and Birmingham so you are not the only person in that area. I'm a little further north near York. I am sure some one on here will be close enough to give you a hand if you need it.

Good Luck!

[daveimi]

I'm in Blackpool if that's not too far. The main reason springs don't get used, even though they store a lot of energy, is because you need some sort of big and complicated way to re-cock it after firing. (which adds complexity, will go wrong when your getting battered and thrown about etc.)

Best way is think about the end result you want and then work on the simplest way to achieve it for reliability.

[Garfie489]

Regarding specifically the idea, it has been done before (Diotoir i believe was spring powered) however it does have its potential problems. Namely the slow return, and also being the least powerful of the common mechanisms.

What you get for that is simplicity, uniqueness, and ease of continued use (once built). Also its something you can just charge up and play, which is always a bonus when starting out. Only potential problem is because its so rare, it may be difficult getting help unless you post an idea and get it "double checked". But certainly at the end you could have a very serious robot which is easy to use and maintain.

Oh btw, you may be thinking of featherweight rather than lightweight.

[Will]

You're right I'm thinking of featherweight - at the small end of the scale where costs are small and everything can be built on one desk without needing any special lifting equipment but not too small to be a pain to build!

I'll try and find a build thread for Diotoir. It might help to see what others have done, even if the scale is different.

With regards the re-cocking of the spring, I was thinking a steel cable that can just be released and then wound back up, or perhaps designing it so it could be re-cocked faster using the entire machines drive system, like into a wall or something.

[jonophilpott]

Small and cost don't normally come in the same sentence í ½í¸‚

[Will]

Well I was thinking, motors, gearboxes, batteries etc are all much cheaper if you're looking for small ones rather than big ones something to move 100kg around. All relative of course, I'm not fooling myself thinking this will be knocked together for £10 or even £100.

[Liftoff]

Well I was thinking, motors, gearboxes, batteries etc are all much cheaper if you're looking for small ones rather than big ones something to move 100kg around. All relative of course, I'm not fooling myself thinking this will be knocked together for £10 or even £100.

How about pneumatics to cock the spring? Have plans for something similar...

[bigsi]

How about pneumatics to cock the spring? Have plans for something similar...

Your pneumatics have to develop more force than the spring to be able to compress it - so there must be an argument for just using the pneumatics and not bothering with the spring!

Si

[Liftoff]

Your pneumatics have to develop more force than the spring to be able to compress it - so there must be an argument for just using the pneumatics and not bothering with the spring!

Si

Thats right, agreed. The main argument for the spring rather than pneumatics is the simpicity of the air system required to close the spring when compared to the air system required as a flipper. For an effective flipper using LP pneumatics you would require a buffer tank, large bore fittings and qev etc, basically you need a system which is optimised for flow and that takes up space.

On the other hand, if you use a spring, you get instantaneous power without the related problems of flow etc on pneumatic systems. The pneumatics to close the spring will not be effected by port sizes and flow etc because it does not matter if it takes a couple of seconds to cock the spring.....I think a set up with springs takes up less space and can possibly be more powerful...that said, it is not straight forward to build as it's not something I've seen built, so there's not much help around or build projects from where to take ideas.
I have a CAD design of one, which I'd like to build at some point...but I need to find time for it!