Speed against time(continuous)
Low speed acceleration is actually quiet good, which doesnt make much sense given the vehicle is accelerating in the worst possible gear with the engine completely out of its torque band.
It’s almost like they have tried to model torque multiplication, causing oddly high, low speed acceleration, even when out of band.
Although, the mid to high end appears to be modelled relatively accurately actually, the differences in accel are wayyy too small tho.
+1
Between this and regenerative steering, all high tier tanks need this.
Just because T-34s and KV-1s had only clutch steering doesn’t mean modern ones should be stuck with that alone.
+1, engine torque is something that is desperately needed in this game.
absolutely dead and buried post but i think they must have some kind of power difference between engines in the game since they specify that engines have power at a certian rpm.
for example the leo 2 has 1500 at 2600rpm, leclerc has 1500 at 2500rpm and the abrams has 1500 at 3000rpm (because turbine). Is the rpm value just for show then or does that mean the leclerc has more power at low rpm and therfore better acceleration? I have alway wondered about this and i would love if people looked into it more.
Note that i forgot but this could be another way to balance the game. I am of the opinion that the tank factors that are classified should be used to balance that tanks since you cant just model them like real life, leaving them open to be changed in whatever way you want. (within realistic margins of course)
You could reenforce the leclerc’s role as a speedy fast accelerating tank by buffing its troque to make it more competitive, since it pales in most aspects compared to the other top tier alternatives.
I did some follow-up experiments on this topic, and here are my results.
Method
I used Pzkpfw III J1, which has no torque converter nor CVT. A gear was selected manually. The vehicle speed and acceleration of a Pzkpfw III J1 were measured on the runway in Cargo Port map. Time for the tank to reach 2 kph from 0kph, 4 kph from 2 kph, 6 kph from 4 kph, … , were calculated from the obtained data, and acceleration for each velocity was calculated. Acceleration characteristics were measured 5 times and obtained acceleration data were averaged.
Results
First, I would like to show one of the raw measurement data.
The black line shows the selected gear, and the blue line shows the vehicle speed. Most noticeable in gear 6, the speed curve seems similar to the previous reports in this topic. Similar 5 results were processed and acceleration characteristics of the tank were obtained.
Here’s the relation between tank acceleration and vehicle speed.
I must note first that there is a greater error in low gears because the vehicle speed has increased too quickly. However, with all the gear ratios, vehicle acceleration seems to be exceptionally high at low speeds, less than approx. 8 km/h. This threshold velocity seems to be the same for all the gears, and regardless of engine RPM.
I also calculated the powertrain output. Output power can be calculated by multiplying vehicle mass (kg), acceleration (m/s^2) and speed (m/s). This formula ignores the friction that the vehicle receives from the terrain, but I consider it to be a good basis on which we discuss.
As seen clearly, peak output seems too small, and greatly differs among each gear. A Pzkpfw III J1 is supposed to have 300 hp peak performance, and the engine output should not be affected by the gear ratio. Of course the vehicle faces more friction at higher speeds, but I think this result cannot be explained solery with friction.
So, I divided the engine output with corresponding gear ratio, which makes no physical sense at all.
The “engine output” seems more viable this time. The peak output is more aligned, especially for 5th and 6th gear (purple and brown). For the other gears, the high power range might be truncated, and hence appear to have lower output. Also, it seems that something like “common output power” exist for low velocity regions. From this result, it is likely that the developer team wrongly applied gear ratio not to torque but to output.
I also tried to estimate engine torque. Engine output P = 2πnT, where T is engine torque and n is engine RPM. So engine RPM is needed to calculate engine torque from output power. However, I found out that engine rpm shown in game is not what we can rely on.
The engine RPM and vehicle speed are not proportional, even in conditions where the clutch should be fully connected. Engine RPM seems to follow something like n = cgv + n_min, where c is a constant, g is gear ratio, v is vehicle speed, and n_min is the minimum RPM. It should be n = cgv when clutch is fully connected. Also, in-game engine RPM data seems to respond after the vehicle speed changes. This might be to recreate the tachometer response in real life. So I also tried to calculate engine RPM from vehicle speed, but I couldn’t figure out the proportionality constant.
Conclusions
Acceleration characteristics of Pzkpfw III J1 tank was measured on a runway in Cargo Port map.
It is likely that the developer team wrongly multiplied engine output when they implemented gear shift mechanism instead of engine torque. Therefore, this tank has excessive acceleration (torque) with low gears, and low output with high gears. And it was found that the acceleration at low speeds, less than approx. 8 km/h, is exceptionally high. However, this might be necessary to aid tanks to move and rotate at very low speeds. Engine RPM, which seems to be calculated after vehicle speed, is also not calculated correctly. So, let alone engine torque, none of the power output, engine revolution and clutch operations are correctly modeled.
Of course War Thunder is a game, and has to be fun to play. If it is too hard just to move a tank, it would ruin player experience. However, current implementation cannot reproduce the individuality of each tank and is reducing attractiveness.
It will be a hard rework since modification on the base powertrain model will affect all the tanks. But I would love to see tanks with their unique drive systems running around.
Excellent Work, Think you’re on to something.
the wolfpack has a 10 speed gearbox lol additional gears indeed