Combat Forces for Finite Element Analysis

[Eventorizon]

Being a student I am lucky enough to have access to both Solidworks 2012 and Autodesk Simulation 2012, and I was going to use both of these to help optimise the design of my robot, Shrapnel. But I am missing a few critical numbers so...

In combat what could be considered a typical value in Newton€™s/kilograms for the following scenarios:

Smashed against the arena wall by another robot at speed
A collision between two robots driving straight at each other at speed
Hit by a high speed spinning disc at full speed
Landing from being flipped

I am just looking at the worst case scenarios here, so who had the fastest robot, the most destructive disc etc

Thanks Alex

(On a slight tangent but still important, what is a good thickness for the base of a robot. The design is currently at 4mm 6061-T6 Aluminium but I am thinking that might be overkill, any ideas)

[typhoon_driver]

Re: Combat Forces for Finite Element Analysis

Don't bother. Having carried out a very basic FEA on a spinning disc I came to the realisation that it's pointless and very difficult to put figures to things.

You can do the basic sums from kinetic energy calcs when it comes to robots hitting each other. For the discs take a figure of around 5kJ of kinetic energy and assume that everything is transferred (never happens) in a certain angle of rotation. You can take the sums further from there.

I was once told by an engineer Stop measurebating and get building. Take from that what you will.

Regarding the base, 4mm will be fine, you could get away with 3 or even 2 depending on the rest of your structure.

[Eventorizon]

Re: Combat Forces for Finite Element Analysis

Yeah, its overkill. Though until I get some money CAD and the wooden prototype are all I have.

I am guessing for first time builders that the first robot will have to be along the lines of, 'you have done your best, now bite the bullet and build the thing', but after 9 months of designing and developing and prototyping the last thing I want is to see Shrapnel get turned into its namesake!

[PJ-27]

Re: Combat Forces for Finite Element Analysis

You build it, it breaks, you fix it, make it stronger, it breaks, repeat until awesome!!!!!!

Trial and error in the arena is the best way to learn, and given that full combat events are currently once a year some of the guys that have been going a while have a major advantage.

The huge variety of robot designs in the FWs though means it impossible to build the perfect robot and you have quite a nice Rock, Paper, Scissors effect going on.

Oh and even the best robots break!

[elobire]

Re: Combat Forces for Finite Element Analysis

My advice would be not to bother with them. I doubt the simulation would be anywhere as realistic as you expect because there are so many elements involved.

Just be patient.I have waited 2 years for the funds to build my robot.

I guess no matter how many simulations you create, it will not be more effective than experience.