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*dead*

PostPosted: Fri Mar 06, 2015 1:13 am
by pnvv
Goal here - build an engine which has the best power-to-weight ratio.

Rules -
-Must be spawn, any configuration allowed
-Max Hz 140 (That's what I use)
-Max size 2x2 m
-No weight limit, but spawned geoms don't count.
-May use laser or collide-based ignition but must only spawn one geom per cycle (basically every piston can only spawn 1 geom per revolution), and that geom must fit in the chamber (However, this does not apply for rotary engines such as wankels, that don't have a fixed "cylinder" size.)
-Engine must give it's output through rotative motion. You can't just build a rocket...
-Has to be reasonably stable, and give full power for at least 15 secs. It can't just explode immediately....
-Max InertiaMultiplier = 2
-Must attach engine to background using hinges or springs, no gluing. Your engine mounts may protrude outside the box if necessary.

Scoring -
Only one category - horsepower per kilogram. The person with the highest power per kilogram wins!

Entries must be submitted by June 5th, and you may have a maximum of three separate entries, but you may modify those engines for more power if you want to as long as you don't just build an entirely new engine.

I will make and update a leaderboard on this thread - the person at the top when the contest ends wins, and the winner gets a nice trophy image to put in your sig!

Base scene. Post entries as a response or in this thread!
Rating: rated 5
Filesize: 7.95 kB
Comments: 0
Ratings: 1
download


An engine I made eons ago that I just tweaked a little to fit this contest. I'm not participating myself, this is just an example of a good entry.
Rating: rated 5
Filesize: 68.51 kB
Comments: 4
Ratings: 1
download

Re: Power density contest

PostPosted: Fri Mar 06, 2015 3:59 pm
by Kilinich
~10kW/kg :twisted:
decreased to 2.5kW/kg for stability

[scene]96509[/scene]

Re: Power density contest

PostPosted: Fri Mar 06, 2015 4:01 pm
by Kilinich
"May use laser or collide-based ignition but must only spawn one geom per cycle"
That needs additional explanation. What cycle? In whittch chamber? Is it allowed to use single chamber for few pistons?

Re: Power density contest

PostPosted: Fri Mar 06, 2015 4:17 pm
by pnvv
OK, I tweaked the rules a little based on what you said. But I still have to test your engine :thumbup:

Re: Power density contest

PostPosted: Fri Mar 06, 2015 5:43 pm
by Kilinich
"basically every chamber can only spawn 1 geom per revolution"
does that mean not more than one piston per chamber?

Re: Power density contest

PostPosted: Fri Mar 06, 2015 5:51 pm
by pnvv
No, the amount of pistons per chamber is only limited by the amount of collision layers you have available :)

I only mean you can't use multiple geoms per piston.

Re: Power density contest

PostPosted: Sat Mar 07, 2015 12:15 am
by Kilinich
Also, I'd rather you add rule not to glue/fix engine to background (density of body does not matter in that case).
And, if you wish, limit inertiaMultiplier to some value (physical maximum is 2 for circle, where all density at edge ring).
And, it's worth to say, solver for contacts should be iterative. :ugeek:

Re: Power density contest

PostPosted: Sat Mar 07, 2015 10:20 pm
by pnvv
But it won't run w/o blowing up....

Iterative contact solvers is a good idea; i'll add it. Also the InertiaMultiplyer thing, I'd say a good limit is 2 as well.

Re: Power density contest

PostPosted: Sun Mar 08, 2015 8:06 pm
by Kilinich
pnvv wrote:But it won't run w/o blowing up....

Iterative contact solvers is a good idea; i'll add it. Also the InertiaMultiplyer thing, I'd say a good limit is 2 as well.

Thats why i ask about stability... I dont have issues on my pc, but there could be problems on others. To judge stability you need to set less sim speed, like 1/2 or less.

Re: Power density contest

PostPosted: Sun Mar 08, 2015 9:20 pm
by pnvv
But if it runs at lower sim speed, that would be cheating.

And even at lowered sim speed, it still explodes.

Re: Power density contest

PostPosted: Mon Mar 09, 2015 9:40 pm
by Kilinich
ok, let's try to make it stable in your enviroment)
I've decrease spring strength and load.
2.5kW/kg
Please check it.
[scene]96509[/scene]

Re: Power density contest

PostPosted: Mon Mar 09, 2015 10:23 pm
by pnvv
It still explodes.

I even got rid of the load and it exploded. Hmmm...

Re: Power density contest

PostPosted: Mon Mar 09, 2015 11:50 pm
by Kilinich
pnvv wrote:It still explodes.

I even got rid of the load and it exploded. Hmmm...

Try reset config. I've record video showing no problem with any load on any sim speed.
Do you use aLgodoo 2.1 ?

http://youtu.be/rpzEWqtfJqw

Re: Power density contest

PostPosted: Mon Mar 09, 2015 11:54 pm
by Kilinich
I couldn't start your example:

http://youtu.be/dZboPrAxDO0

Where is load on your example? How you measure it? :wtf:

Re: Power density contest

PostPosted: Tue Mar 10, 2015 5:32 pm
by pnvv
That's so weird!!

Load is measured on axle in middle, and it increases with rpm. so try disabling it, hauling on flywheel to get it started then reenable it again.

Re: Power density contest

PostPosted: Tue Mar 10, 2015 10:11 pm
by Kilinich
I don't see any point in number of spawned geom limitation. It's really doesn't matter if you spawn two or one with double density.
Also, you should describe how to measure power, how to place load. I recommend you to draw 1m radius circle with at least same mass as engine and put brake hinge on it

Re: Power density contest

PostPosted: Wed Mar 11, 2015 12:19 am
by Kilinich
Another notice: since you don't count spawned geom mass it could be virtually +inf. That means it will not move at all during cycle, makes engine more powerful but unusable )

Re: Power density contest

PostPosted: Wed Mar 11, 2015 11:36 am
by Kilinich
(However, this does not apply for rotary engines such as wankels, that don't have a fixed "cylinder" size.)
oh cool, just build propeller with spawners on it and it will give virtually ifinite power :clap:

[scene]96837[/scene]

That's what happenet if contest rules not worked out well :thumbdown:

For better contest you need:
1) Limit weigh, limit density
2) Count engine weigh with particles
3) Describe how to measure it's power/weight ratio
4) Measure thrusters effect of spawned geom

Re: Power density contest

PostPosted: Wed Mar 11, 2015 4:47 pm
by pnvv
...screw this. I give up.

Re: Power density contest

PostPosted: Wed Mar 11, 2015 5:18 pm
by Kilinich
pnvv wrote:...screw this. I give up.

don't give up, it was good idea for contest, you just need more expirience)

Re: Power density contest

PostPosted: Wed Mar 11, 2015 6:02 pm
by pnvv
...yeah. I really don't have the algodoo know-how to run contests anyway.

Re: Power density contest

PostPosted: Fri Mar 13, 2015 2:58 am
by s_noonan
Good contest. How else would we get Kilinich to make the strongest engine in Algodoo? Maybe the next contest could be a fuel efficiency contest where we track the total energy produced divided by the total accumulated mass of the spawn geometries.

Re: Power density contest

PostPosted: Fri Mar 13, 2015 4:02 am
by pnvv
God I wish I could delete threads, cause this has been a complete disaster.

I do have an idea for another contest, Mars rovers. Basically it has to transport cargo a set distance with Mars-like gravity, But unlike Kilinich's contest which was very similar you get to make your own engine and such.

Re: Power density contest

PostPosted: Fri Mar 13, 2015 11:35 am
by s_noonan
You could do a Power Density Contest II where you take everything you learned in this contest and use Kilinch's suggestions to make the contest more restrictive. I may have screwed things up for you because I tend to look for loopholes that can be exploited. I could stay out of the next contest to make things easier for you. You could require a compression stroke, which would disqualify Kilinich's and my rotary engines.

Re: Power density contest

PostPosted: Fri Mar 13, 2015 2:10 pm
by Kilinich
Great idea about "fuel" as spawned weight count!