WIP Beta released Citybus Hybrid 8.1.0

Huh; I wonder how I let that regression slip through. I had fixed that in a previous version (it's trying to aggressively charge the battery, which produces forward torque)...I'll look into why it's happening again.

 

Arcanox updated Hybrid Citybus with a new update entry:

Better Efficiency!

Read the rest of this update entry...

 

The update is fantastic. When inrease throttle the electric consumtion goes up to accelerate the ICE, then goes down, when decrease throttle it use regen to slow down the ICE before return to 0kW, making the engine adequately loaded even when moving throttle
Bug: The mod overide the buses' key binding, making. instead of max height, kneel right etc. Manually rebind the key is possible, I'm ok with it.
The brake pedal indicates brake pad engagement and not the driver's brake application

 

Great update, it does seem to manage the engine a lot better now. However, it still likes to lug the engine a bit too much sometimes. The ETK800 hybrid sport seems to get better highway mileage than the hybrid eco model, because the eco engine gets lugged and spends most of it's time at 100% load, and the same can be said for the Wentward under certain occasions. Probably just needs some fine tuning on the load vs RPM logic, and rev a bit higher to try and keep load under control. Interestingly, all 6-cylinder ETKs get better highway mileage than all 4-cylinder ETKs, because the 4speed revs too low and gets lugged badly by the automatic trans (it could probably use a slightly shorter final drive). I didn't test too much though, so if you think the logic is fine as is don't worry. Keeping the ETK800 at highway speed with such a tiny engine is gonna load it no matter what, and my testing techniques weren't exactly perfect (driving back and forth on WCUSA with the throttle pinned at around 25%)

Also, the bus hybrid transmission causes a vehicle error if you install and engine that doesn't have a turbocharger with it. The turbo pre-spooler throws an error in the console.

 

Note: The configs are using the modded 3.0L I6 Eco Engine that is slightly different than the BeamNG official engine. To get an accurate measure of the MPG improvement of (only)the hybrid drivetrain, set the initial battery charge to 60% and use the non-modded engine is recommended

 

The Eco engine is basically the same engine but with about 15% less torque, the idea being that it's running on the Atkinson cycle instead of Otto, which is what all hybrid vehicles that I know of use (even the 6cyl Highlander hybrid uses Atkinson).
--- Post updated ---

I probably need to add a parameter to limit the maximum torque that can be demanded of the engine so it can stay a little bit under 100% load, although the bus does need as much torque as it can get especially when driving up steep hills. I may be able to tweak the engine's input gear ratio a little to improve that.

The bus crashes without a turbo because the prespooler is installed on the transmission jbeam itself...I should have made it its own part. I'll fix that in a minor update

 

Great! and yeah, I'm aware in a lot of cases you really do need 100% of the engine torque, especially in more underpowered vehicles like the bus or ETK800 eco hybrid. Doing some testing, (using the 2L diesel), the eco hybrid transmission will get higher mileage than the stock 8-speed in pretty much every condition, so it's clearly working (I also discovered that the cruise control app PID hates your hybrid, and like half the transmissions in the game). It also seems to act a little strangely when given non-stock engines, the ETK will jerk around the engine RPM quite violently in some cases.

I feel kinda bad writing all this, every time you release a new update we pick apart everything wrong with it. But this mod is seriously awesome, and keeps getting better.

 

I probably need to add a parameter to limit the maximum torque that can be demanded of the engine so it can stay a little bit under 100% load, although the bus does need as much torque as it can get especially when driving up steep hills. I may be able to tweak the engine's input gear ratio a little to improve that.

The bus crashes without a turbo because the prespooler is installed on the transmission jbeam itself; I should probably make it a separate part so it can be removed if the engine doesn't have a turbo.

No, don't worry about it! I do appreciate constructive criticism because it helps me to find issues I wouldn't otherwise find and thus keep perfecting the system

And yes, I've noticed the same issues with the cruise control UI app...I looked at the code and it doesn't even use a true PID loop. It's implemented weirdly and not tuned right. I should make my own version

 

Fuel Efficiency Test

A typical Utah sightseeing route
10 laps, 96km, more than 2 hours each run, with an average speed of 42km/h. Note: The fuel efficiency in the "trip computer" is inaccurate, use "engine debug" or any app that can acually display the remaining fuel.

Open rear differential, 4.04:1 final drive, T350 turbo. The only difference was the transmission, 6AT vs CVT vs eCVT.

6AT 47.75L/100km or 4.926MPG


CVT 41.73L/100km or 5.637 MPG (14.4% improvement)


eCVT 38.24L/100km or 6.151 MPG (24.9% improvement)

 

Nice! I have a hard time breaking 5.5 on Utah routes, but I do the bus routes which are usually one-way up hill. I have a version of the trip computer app that I fixed to properly use "total distance traveled divided by total fuel consumed" for the MPG, so it's actually accurate. That's what I use for my own hybrid MPG benchmarks.

 

I did these tests in Freeroam without resetting, not Bus route, since you need to set the battery level at 50% (60% in the tuning menu) before the test to prevent excessive electricity from giving an overrated MPG.

 

The latest update was supposed to fix the conflicting keybinds, but I think the switch from 4.0 to 5.0 resets your current bindings because I changed the name of my input_actions.json file. This is a one-time thing, and the fact that I renamed mine from "input_actions.json" to "input_actions_hybrid_arcanox.json" means that there will be no conflicts in the future, ever, since I have my own bindings file now.

The problem before was that I hijacked (replaced) the bus's input_actions.json. I don't know if the "layered bindings files" feature is new or if I just didn't know about it before, but I read about it on the wiki recently and migrated my mods to use layered files instead of replacing the default ones.

 

Arcanox updated Hybrid Citybus with a new update entry:

Tweaks and bug fixes

Read the rest of this update entry...

 

Creep in L is slower than D, is that intentional? nice feature

 

It's not necessarily "by design", but rather a side effect of the fact that the bus is geared so high that the regenerative braking is able to slow the bus down to below 5 MPH (which is the "creep speed" of my hybrid transmission). In L, regenerative braking wins over creep, so you end up with a creep speed of somewhere between the minimum speed of regen braking and the 5 MPH of "D" creep.

 

Is it a known issue that the bus refuses to charge once the battery hits 0%? It'll lock itself in park and enter charge mode, but the battery won't charge at all. Is this modeling the need for the windings in the MG to be charged beforehand in order to generate power (at least, if it isn't using a permanent magnet), or is it a bug?

 

It should definitely charge up from 0% as long as the engine is running. Would you be able to record a video of this problem happening?

 

Seems to have fixed itself while I was trying to reproduce it. It does charge after a while, it's just that the UI app still reads the battery at 0% after it finishes. Have to go into EV mode to get the battery charge to show up. Sorry about that.

 

Ah, that's because the UI app shows the "usable region" of the battery, which is less than the actual battery capacity (as is the case with all real-life Lithium batteries). I believe on the bus it's either 25% or 30% to around 90%, so if it's outside that range it will just show 0% or 100%.

 

I am not sure which update this occurred in but I recently I noticed the bus top speed is now 80 mph instead of 110 mph and hybrid mode doesn't use all of the electric motor power. I feel like the top speed and power reduction takes away from the idea of a racing version. I am not sure if this was to make it more realistic or more efficient but it the old bus was simply more fun to drive around the maps. Most mods have versions of their vehicles that are stupid but fun and I recommend a version of the bus like this.