Anonymous at Fri, 29 Mar 2024 09:34:40 UTC No. 16103049

>>16102680
I think the rollers are frictionless. apart from their inertia. but if you'd incline it (to simulate driving uphill, have all juices in system sit in natural position for that inclination) and add friction to the rollers. like brake them a little to make the car work harder. that's it.

Anonymous at Sat, 30 Mar 2024 05:53:23 UTC No. 16104404

>>16103049
thanks for the reply anon. im still not convinced, in my head the load on a car going up a hill should be far higher, and I don't think its due to friction

I think the best model of this would actually be some type of rope tied to the back of the car pulling it backwards. very hard to simulate on a machine like this

Anonymous at Sat, 30 Mar 2024 06:18:39 UTC No. 16104440

>>16104404
Yeah normally if you want to test an engine at heavy load you are doing it with the crankshaft directly connected to a force sensor and then to some sort of load so that you can provide resistance and measure how much force the engine is generating at a given RPM.

Anonymous at Sat, 30 Mar 2024 22:22:10 UTC No. 16105480

>>16104404
what are you interested in measuring? you don't expect shock performance on such a test, so I suppose you are interested in engine performance and transmission stuff. if you incline the rig, secure the car at an angle, and figure out adherence, you only have engine performance. which does what when going uphill? works harder to move the wheels, which seen in reverse is the ground being harder to move. as in having extra friction on the rollers. just that you'd have to math out how much considering car weigth/angle.

Anonymous at Sun, 31 Mar 2024 23:47:52 UTC No. 16107022

bump

Anonymous at Mon, 1 Apr 2024 00:21:09 UTC No. 16107065

>>16107022
really?

Anonymous at Mon, 1 Apr 2024 00:21:10 UTC No. 16107066

In my mind, the main difference between an inclined test machine and an actual hill is, when driving up a hill, the car is overcoming gravity, requiring more energy per distance. While on a machine, I imagine the majority of the mass isn't actually moving at all.

Anonymous at Mon, 1 Apr 2024 18:35:32 UTC No. 16108039

>>16107066
>In my mind, the main difference between an inclined test machine and an actual hill is, when driving up a hill, the car is overcoming gravity, requiring more energy per distance. While on a machine, I imagine the majority of the mass isn't actually moving at all.
Yes, actual work is done, you're building up potential energy when driving up a hill.
If the rollers are frictionless, this work is not done, no matter (in a reasonable range of course, as long the car doesn't just fall off) how much you incline the whole thing.
You can however simulate it if you can set a resistance to the rollers. No inclining needed for that.
Have a nice day!

Anonymous at Mon, 1 Apr 2024 18:41:18 UTC No. 16108045

>>16108039
>No inclining needed for that.
technically not true. because while flat there's different amount of weigh on the front axle, if inclined that means less, which means less grip.
ideally you'd also incline it, and when you lose grip it would be equivalent to spinning your wheels while trying to climb.
but sure, just for engine performance and nothing else just add friction to rollers.

Anonymous at Mon, 1 Apr 2024 19:14:07 UTC No. 16108088

>>16108045
Your right of course, thank you!