Concerning the new power to wheel to weight ratio calculation

My vehicle used a RV as a base and I haven’t completely populated it with parts, I’m still looking for those ever elusive Ice Cream trucks :frowning:

I’ve only found one, but I pillaged its minifreezer. Its nice.

They are and I’m pretty sure that a mod like Malkeus’ version of Cata++ has a bigger version just like the fridge but I’ve only seen the recipe once and never found it again

Roller drums have much lower rolling resistance than treads, and he might have better aerodynamics though I can’t tell. Since rolling resistance is proportional to weight, you’re taking a hefty penalty for those treads.

Also, 2 enhanced engines have 1.6x as much power as a single enhanced engine, while 7 engines have 2.8x as much power as a single enhanced engine. That’s how CDDA has always handled multiple engines, so there’s no change there, but you’re burning a lot of juice for not a whole lot of extra power.

Things that will help:

  • use aerodynamic designs with halfboards up front, followed by windshields
  • try to avoid having full boards and aisles on the same vehicle, especially on the same column as a turret because that raises your vehicle height.
  • narrow designs have less air resistance than wide designs - though the penalty for the 6-11th tiles is a lot less than the first 5, so there’s not as much payoff there.
  • armored wheels, rollers, or standard wheels give better performance on roads than treads - though your off-road performance may suck

Sadly, any realistic performance calculation is going to make massive, multi-engined mega-vehicles burn energy like crazy without necessarily going very fast.

One thing that would probably help - and that I support but may have problems getting merged - is providing REALLY LARGE engines. A M1 Abrahms tank doesn’t have 5 diesel v8s, it has a single 1500 HP turbine. Fuel consumption is still awful, but not nearly as bad as 5 diesels would be.

Do floor trunks count as aisles? Do stowboards count as full boards?

I don’t have a single full board or aisle on my vehicle, but I’ve got some floor trunks and stowboards.

I could definitely use an electric equivalent of the abrams gas turbine engine.

Stowboards count as full boards.
Floor trunks have always counted as aisles - the code checks for the “AISLE” flag, which is also the flag that reduced the penalty for moving through a vehicle tile.

what do storage areas or cargo dimensions count as?

Cargo spaces and cargo dimensions don’t add to vehicle height.

My only concern with huge engines is making the size, maintenance and installation requirements reasonable.

Maybe we do something fairly elaborate, or maybe we just support them by having them appear already installed in vehicles, and the only way to interact with them is to modify the vehicle around them.

You could always just adjust motors to act in parallel instead of the diminishing returns setup. Or just lessen rate the returns diminish.

I think with mark looking at holistic vehicle efficiency, we can switch the system over to being based on the property that large engines are more efficient than an equal mass/volume of smaller engines instead of the artificially inflated power loss from stacking multiple engines (though as I understand it, those losses do exist). I have to stress though that im pretty sure any system we come up with will work best with one large engine.

2 Likes

On the more cosmetic side of things, since these variables are pretty obscure and hard to reason about if you don’t know about them, it would be nice to have a more detailed overview in game for at least some of these:

“The turret sticks out a lot, it will increase drag”
“Installing more engines will give diminishing returns. [Perhaps you could find a larger engine?]”

And for the threads vs. other “wheels” there should probably be either more transparent numbers or similar descriptions. (“Threads: good for offroading, but in general not as efficient as other ways of moving about”).

1 Like

Yeah, I’m working to improve the information display.
But in my defense, this was a huge and hard piece of code to figure out, I wanted to take a break for a few days.

1 Like

Its still a good update. My old speed was ridiculous. I could go 90mph IN A TANK.

I’m working on tearing down and redesigning my tank now. I shaved about 2500 lbs off by replacing all except the exterior 2 layers of tiles with regular frames instead of heavy frames, and 2 enhanced electric motors is now enough to get it moving I think. I used to need 4 to even make it budge. Its still going to be at around 55-60k lbs, but it should be more efficient than if I had left it as is.

Some things that would be EXTREMELY helpful:

  1. A number to indicate gas mileage/battery usage rate. Like in charge/tile or mililiters/tile or something.
  2. A number to indicate how fast your batteries are currently being charged, such as from solar panels, minireactor, etc.
  3. A number to indicate current electricity consumption rate.

Yeah, those are pretty much the goals, along with an estimate of when your batteries will be fully charged or fully depleted.

I’m probably not going to include reactor power, because reactor power is basically “your batteries will be fully charged in 30 seconds or you will run out of plutonium cells.”

Alright, so I retooled my tank, I’m getting much better performance than earlier. I can run it at decent speeds with only 2 enhanced electric motors, with 2 more as spares. That acceleration is gonna be problematic if I need to run anything over from a dead stop, but hopefully it will be fixed soon. I cut about 10,000 lbs off of it by swapping some heavy frames for regular ones, and unloading excessive crafting materials & spare parts. Eliminated the aisles and floor trunks too, and replaced them with another layer of armored quarter panels up front. Added 2 more solar arrays as well to help keep up with the power consumption, for a total of 6.

You if anyone deserve to take some time off if you want to, your contributions are gold =D

A case for including nuclear power into the “cosmetic upgrade” - if it’s easy enough at least - is specifically for the same reason you don’t want to include it, because part of the fun in having overpowered stuff is the “oooh, lookit the numbers go!” part =P. And I would say theres a case to be said to just having things be consistent.

Current implementation here:
https://github.com/CleverRaven/Cataclysm-DDA/pull/27089

If you have suggestions for improvement, please read the PR and make them there.

2 Likes

If every single one of the treads is broken, and they are, the speed should be 0, not 4.

It doesn’t matter if I put an FTL warp drive in it, it cannot move.

In fact, there was an Atomic Mini-Tank that had one broken motor and one in horrible condition, but it had all of its treads intact, and its speed was 0.

Don’t roller drums weigh over 3/4 ton each?

I was going to propose power adders. Instead of 5 diesel V8s, you would have a single twin turbo diesel V12, ala M60 Patton.

The aforementioned diesel V12 (or the naturally aspirated one in the Challenger 2) has much better fuel consumption than the turbine in the Abrams. The main benefit of the turbine engine is that it can run on virtually anything that is flammable. Liquor stores become gas stations. (Maybe add a “Mixed fuel” fuel tank type for this for simplicity) Turbine engines also have the same efficiency regardless of how fast the vehicle is going.

In my opinion, HUGE engines would absolutely be the way to go. Possibly make the HUGE ones impossible to install in anything below a certain weight class. Boom crane required, obviously. I can at least visualize how I can fit two 12-liter V12s in my Hatchback, but a 29-liter would be almost as big as the car.

Electric motors always report speed 0 until you turn them on for the first time. Not 100% sure why, don’t care enough to spend a couple of hours debugging the issue.

Possibly? But rolling resistance is the sum of each’s wheel’s rolling resistance, times a small fudge factor for having a lot of wheels, times the entire vehicle’s weight. For the same set of wheels, heavy vehicles have more rolling resistance than light vehicles, and for the same vehicle weight, treads have much more rolling resistance than rollers. Put the two factors together and heavy vehicles on treads have a lot of rolling resistance.