Quote from Egor K :

...when camera is selected please show eyes coordinates...

In addition to the previous suggestion, also for the sake of unification, I've combined camera control suggestions in one post, and since in general they are needed when creating a vehicle, decided to post them in Mod System Suggestions section. So:

Rotate view by arrows as "RMB + mouse movement" alternative

in LFS free-floating camera (Shuft+U) control: Ctrl + left/right arrow used to roll; Ctrl + up/down arrow used to adjust height, but rotation (yaw and tilt) is only possible with mouse; in LFS Editor in 3D view same as free-floating camera in LFS; in 2D view Ctrl + arrows used to rotate model. It would be handy to unify controls (LFS and LFS Editor: Vehicle Editor and Modeller):

This will allow you to calibrate yaw and pitch separately and precisely, besides, combined with panning (only arrows) all camera manipulations can be performed using buttons.
BTW now in order to isolate rotation axes and increase accuracy of rotation I'm using Mouse Keys from Windows Ease of Access Center.

Display of camera coordinates and angles (both in LFS&LFSE) and store custom views (already available in LFS)

In LFS Editor:

In LFS free-floating camera
This will allow to compare projections from the same point of view and perspective between LFS/LFSE and other 3D editors so that, having received images, you can instantly switch between them and clearly see the difference in shading, etc.;
or, for example, to demonstrate differences between mod versions like I did in this post, but could not accurately match shots from LFS and renders from Blender. Although this can be done using Custom View, but only approximately:
firstly, coordinates are set not from vehicle origin, but from driver's eyes, which makes precise comparison difficult;
secondly, range is a maximum of 2m width, 3m length and 0.6m height in each direction.
Maybe it would be useful set camera background image in LFS Editor 3D view, position and orientation of which can be obtained from camera matching programs such as fSpy.
Also add slider to set Focal Length (for 36 mm sensor size) or Field Of View and buttons with typical lens focal lengths for fast switching.

Since you already made the front-engine 400Z, this time make a mid-engine car to diversify the class.

Quote from k_badam :

What about mclaren artura?

Artura is a hybrid so for now you can't really recreate it.

Aerodynamics > Lift (Downforce)

Quote from Driving Ambition page 76 :

Initial targets were a realistic 0.35Cd, CoP almost coincident about the centre of gravity and 160lbs (712N) downforce at 150mph (241km/h).

Quote from Racecar Vol6 No1 page 35 :

According to Murray, the McLaren F1 road car produces 500-600lb lift at its road maximum speed, at which it is able to cancel this lift and leave a nett 200lbs downforce.

Here's the tricky part, if stated downforce (200lbs or 890N) is correct for top speed of a serial car 221 mph or 98.8m/s, then by quadratic function at 150mph or 67.1m/s it will be 93lbs or 411N, which is 58% of the Initial target. Perhaps downforce generated by fans reaches maximum already at 150 mph and does not increase further because their speed can be controlled by some program.

Also print-out of tunnel 3/10 scale model run results is used as an illustration on Driving Ambition page 74, this one and above data summarized in table below.



Anyway, I see no reason to assign less downforce than planned, so 0.158 N @ m/s is chosen.

Spoiler - click to reveal

Have to mention "BB 'Foil" (spoiler), however, LFS currently doesn't simulate active downforce.

Quote from Driving Ambition page 79 :

Activated automatically by electronic control sensing heavy breaking, this "BB 'Foil" would deploy at 30-degrees, slightly raising Cd but crucially enhancing base-suction at the tail to generate greater downforce from the diffuser with its CoP in the right place.

How much "greater downforce" exactly? Gordon says twice:

Quote from Gordon Murray :

We have an active aerodynamic control system on the car which pops up a flap, which not only doubles downforce on each wheel, but doubles downforce in right proportion front to rear axle, so it helps stabilize the car...

Aerodynamics > Drag

Knowing frontal area=1.79 m^2 and drag coefficient Cd=0.32 (ρ is air density) drag force can be calculated, so for V=67.1m/s (150mph) Fd=1580N.

To find body drag for LFS Editor divide drag force (1580N) by square of speed (V=67.1m/s)^2 = 0.351 N @ m/s.
But using this value LFS Estimated Maximum Speed Calculator (hereinafter — LFS.EMSC) indicates 373 km/h (232 mph), moreover acceleration from 255 to 350 takes 20 sec (16 sec IRL) and from 350 to 370 takes 20 sec again (8 sec IRL).

To match LFS.EMSC and Ehra-Lessien 391 km/h (243 mph) XP5 (experimental prototype number five) record run (not to be confused with official two-way average measured 386.7km/h or 240.3mph) body drag must be 0.304 N @ m/s.
Apart from fact that accelerating from 360 to 370km/h and from 370 to 380km/h takes one sec longer than IRL, even across Layout Square is not enough to reach 390km/h.

So 0.293 N @ m/s (LFS.EMSC 396 km/h) chosen because this body drag ensures acceleration coincides across all control ranges with deviation of less than a second.

Version 3 Aerodynamic changes

reduced Body lift from –0.450 to –0.158 N @ 1 m/s
increased Body drag from 0.270 to 0.293 N @ 1 m/s
reduced Side drag from 0.600 to 0.586 N @ 1 m/s

Other changes in addition to those listed here

gear ratios according to Autocar magazine: second from 2.21 to 2.19 and third from 1.68 to 1.71

final ratio from 2.99 to 3.03 to ensure maximum speed with

original starter sound from youtu.be/LSUvgTFp5Ts 0.740s (0.742s max)

original gear shift sound from youtu.be/KXihJTDSWb4 0.180s (0.184s max)

second (right) internal mirror disabled (not supported)

Thanks to Rony for helping me stop procrastination with improving the aerodynamics

Thanks to Martin because I had previously speculatively decided original tacho's four-digit readings must be too large to be readable on low resolution screen, but after he asked I tried and realized I was wrong.

Last edited by Egor K, Wed, 24 Jan 2024 21:55. Reason : "invisible" table reuploaded, listed additional changes

Approaching version 3.

Improved lod3

0.7E patch changes: dashboard, lights, passengers

Realistic dashboard.

with shift light (just like IRL)

Analog speedo with dashboard backing texture can only be used with one speed measurement unit, decided to use mph: after all, it's a British car plus kph dial too small to read on a low resolution screen. But below analog dial is now preferred unit digital speedo.
Still need to do metal pivots covers textures instead of black default ones, but I'll do that on texturing stage
Also added rear fog light icon and now high beam icon works correctly

High beam

Passengers (leg intersection with floor beams is known)

Minor animation improvements

Improved interior shading

However, the most important about new version is improved aerodynamics! Research almost done and I'll post it soon.

D51 upgrade (manually set rear seat width) allowed URC1 passengers to be seated, thanks!

But they sit with slightly shifted feet (example here, here, here and here), so please add feature to mirror passenger animation.

Last edited by Egor K, Thu, 25 Jan 2024 11:00. Reason : added examples from BEST MOTORing

Quote from Scawen :

We plan to fix the bugs and continue developing the Scirocco suspension

Quote from Scawen :

In real life, the suspension geometry is designed to produce an anti-dive effect under braking and anti-squat under acceleration. This has until now been absent from the LFS suspension systems, but now looks like an important development to support the realistic setups.

Quote from book Tune to Win by Carroll Smith :

There are two types of anti-dive front suspension.
The first, illustrated by A, uses brake torque reaction through the suspension links, which are convergently inclined toward the c.g. location in side elevation, to reduce orcancel the diving tendency.
If the point of convergence of the extended wishbone pivot axes intersects a line drawn from the tire contact patch to the c.g. of the sprung mass, then the torque reaction will cancel out the diving moment and we will have 100% anti-dive.
If, for example, we should determine that we want 50% anti-dive, then the line extended from the contact patch through the wishbone axes convergence point would intersect a perpendicular dropped from the c.g. to the track surface at a point halfway between the c.g. and the ground.
The alternative method, illustrated by C is to maintain the wishbone pivot axes parallel to each other and to incline them both downward toward the front. What happens here is that, under braking, the inertia of the sprung mass tries to rotate the sprung mass about the front wheels.
The inclined pivot axes from an inclined plane which forces the wishbones into the droop position which effectively lifts the front of the vehicle.
In this case, to achieve 100% anti-dive, the wishbone pivot axes must be parallel to the line drawn between the tire contact patch and the c.g.
We are using the inertia of the sprung mass to jack up the front of the car.
...
At the rear, the problem with vertical load transfer under acceleration is chassis squat with its attendant negative camber.
It can be resisted by anti-squat suspension linkage.
The same two methods apply, converging the pivot axes toward the c.g. or inclining them upward toward the front.
Once more we are resisting the natural downward force of load transfer with a reactive upward thrust so it is possible to lose sensitivity and get into tire patter and the like if too much anti-squat is employed.

Given the above, I assume a three-dimensional suspension is now a necessity.

Last edited by Egor K, Fri, 20 Oct 2023 20:00. Reason : minor abbreviation changes

Quote from Jardim :

Anti roll bar!

I want the mod to be as accurate as possible. By the way, thanks to terga for link to the explanation:

Quote from interview with Gordon Murray on Carfection (30:04) :

When you look at the basic physics of roll compensation in a car you are trying to stop the roll in a corner. And you can, if you get frequency balance and percentage, you don't get too crazy on the percentage of roll compensation that's coming from the roll bar, you can do it all at one end. The reason why I never do it at the rear is you'll get all this trouble for traction. Particulary in a racing car. To get best bossible traction, best possible independent suspension ... and then you join left and right axles with the bar. It's nonsense. So on one wheel bump or coming out of a corner on roll you're unloading one side of the car. Artificially. Which is nonsense. If you want the best traction — you don't join the axles.

Quote from UnknownMaster21 :

Planning to make GTR version of it?

Yes, but a lot of GTR's specs (such as CoG height, suspension motion range, roll centre and roll compensation, etc.) still to be found.

Quote from UnknownMaster21 :

Or even "no-limit" version?

Also want make 'XP5' version as separate mod (raised redline, speed measuring equipment and fixed black color).

Quote from UnknownMaster21 :

Max Speed I got this vehicle was exactly 400km/h

Official record is 386.7km/h, although XP5 (experimental prototype number five) for 22 seconds kept at least 390km/h: 2:42 — 390 km/h, 3:00 — "not going faster", 3:04 — descending.

Why not let customize hotkeys like in Blender (see attachement), because that's pretty subjective

External mirrors

mesh+SubD, optimized for LFS

Bumper air intake

with flow dividers and intercooler

Transition to mudguard

Rim

Rim dimensions from alibaba.com. Hub dimensions from ZF Product Overview pdf (19.1 MB) (page 6/28).

Models for baking and for LFS tris limit:

Thank you guys for the kind words, although there are still textures and aerodynamics to be completed.

By the way, yesterday model was tested on Sim Racing Bible stream. Phil decided to repeat speed record, but did not reach 240 mph. Thing is for the speed record XP5 (experimental prototype number five) engine redline was raised to 8300 rpm, but URC1 has standard redline 7500 rpm.

For those who want to know more about record run there is "Racing Line" magazine article scans, though text hard to read, so you may use archived page with the same text.

Fog lights: reflector wireframe, material preview, rendered.


Diffuser textures baked using procedural normal map according to tutorial by pyrotechnick.

Bumper rough plastic texture according to tutorial by Golden Monarch.

Headlights inspired by Scania's 2009 redesign. As well as URC1 reflectors created using Extra Objects add-on: Add > Mesh > Math Function > Z Math Surface.

Spoiler - click to reveal

high beam reflector: ( x**2 + y**2 )/(4*.019) focus 19
X=09 and Y=09 subdivisions
Size X=0.17 Y=0.17

low beam reflector: ( x**2 + y**2 )/(4*.055) focus 55 but scaled to fit Z coordinate of boundary 0.08/0.083333=0.96000384001536006144024576098304
X=11 and Y=10 subdivisions
Size X=0.30 Y=0.30

@Gutholz, thanks

LFS Modeller displayed point coordinates accuracy is three decimal places (mm), but in fact points coordinates are more accurate and, for example, points with a difference of 0.1 mm are not automatically fused. Therefore, please increase displayed coordinate accuracy.

Last edited by Egor K, Thu, 22 Dec 2022 13:50.

Exterior progress

I used cabin outline, bumper, headlights and mudguard position from Scania P 250 DB4x2MNA day cabin, not trying to 100% copy though.

Interior progress

No drawings used for interior, eyeballed only. As I said, it's worth the time matching Blender camera to LFS point of view.

For seat and steering wheel position I used drawing about ergonomics.

Steering wheel

During modeling steering wheel form changed but at the beginning I used photo of Scania steering wheel from autoline-au.com.

My mate converting an Iveco truck from box to platform with back mounted crane and since in unladen state rather large mass located at rearmost point it's intersting how it will behave at high speed (high for truck) so I want recreate it inside LFS.

Mass / Object Positions

Some heavy parts mass cannot be set in mass menu, while some of these are unsprung, at least for now only way to set them — tubes, so they will be sprung.

Plan is: place native mass objects, build frame with extra mass objects, make sure weight distribution corresponds to EUROCARGO ML180E25S specs, then add bed and crane.

Mass > Frame (literally)

First I went outside and take some measurements

then modeled frame and bed in CAD and calculated mass per metre to build frame in Vehicle Editor.

Truck frame (without bed and reinforcement for crane load) set to 1202kg.

Mass > Engine

LFS Editor assigns mass of 5883cc engine 294kg. Cummins ISB 5.9L mass is 520kg. So added 226kg, then gearbox 350kg and radiator 99kg.

Mass > Suspension

Front axle of similar capacity mass (with oil and brakes) is 316kg. Front axle set to 283kg.
Rear axle if similar capacity mass is 645kg. Rear axle set to 600kg.

Wheels

By the way, factory truck had all wheels 315/70R22.5 and factory floor had continuous transverse beams that lay on longtitual beams of subframe. But bed must be low as possible to fit taller payloads and for that reason decided to T-weld transverse beams and to use rear tyres with lower profile: 315/60R22.5.

LFS Editor sets mass of four wheels to 176 kg. Conditionally divided mass into six wheels — two front, four rear — about 30kg each.
315/70R22.5 tyre mass is 59.70 kg. 315/60R22.5 tyre mass is 58.42 kg. 9.00x22.5 rim mass is 44.03kg. So one wheel mass is about 100kg, therefore added 406kg proportionally.
Same with spare wheel, but since frame tubes can only be added symmetrically, as well as spare tyre itself can be placed only in center, so additional 44kg is halved.

Mass > Battery

Mass of one Promotive 680108100 — 45.1kg, truck has two. Native maximum 40 kg battery can be moved to the side, but additional 50kg is halved as well.

Wheels, spare wheel and battery additional mass is 500kg.

Cabin structure based on pic from Scania Truck Bodybuilder — Cab Structure (1038kg).

Truck chassis is 5315kg total. Compared to closest in mass Iveco chassis not more than 28kg discrepancy along the axes. It is acceptable.

• IRL — 3440kg (64.2%) front and 1920kg (35.8%) rear;
  
• LFS — 3423kg (64.4%) front and 1892kg (35.6%) rear,
  

So now can add bed and crane.

Mass > Bed

Truck chassis with bed mass is 6034kg (bed 719kg).

Mass > Crane

I made crane with "LFS tubes" model in CAD to make sure COG matches, was only necessary to finish moving parts, cause I've already made model of fixed parts (using drawing from palfinger.com and self measurements) to calculate reinforcements of the frame tail, but that's another story.

Crane 1758kg

Engine

Cummins 5.9L 24V (ISB).

Final drive

Gearbox ratios from ZF 6S800.

Mesh

Current exterior progress
I make cabin and dashboard in Blender as I like, not trying to copy any particular model, but I am inspired by various MAN and Scania trucks.

Last edited by Egor K, Sat, 17 Dec 2022 10:37.

Steering wheel flange rendered using procedural carbon texture (here and below) according to tutorial by Chris Plush.

Steering wheel flange rendered

Dashboard rendered

Closer view from opposite angle. Just to show details.

Icons drawn from scratch, for these I used photos from GTspirit article and photos by Alex Bellus as reference:


and for these I used photo (12/24) from roadandtrack.com:

Improved driver's seat using fSpy to match camera with the photo by Richard Owen (item 65/150):

Last edited by Egor K, Thu, 8 Dec 2022 09:26. Reason : added driver's seat

Approaching version 2. Today's post about exterior progress.

Wiper subobject

Engine+exhaust subobject

Tubes created by converting NURBS curves.
Object Data Properties > Geometry > Bevel > Round. "Depth" sets tube radius and "Resolution" sets transverse polycount.
Object Data Properties > Active Spline: "Order U" sets curve shape transition and "Resolution U" sets longitudinal polycount.

Head- and taillights

Modeled diffuser, bulb and parabolic parabolic focus-balanced reflector for baking lamp textures.
Diffuser textures baked using procedural normal map according to tutorial by pyrotechnick.
Parabolic focus-balanced reflector modeled using Extra Objects add-on: Add > Mesh > Math Function > Z Math Surface. I chose low-beam headlamp reflector focus=23mm Z Equantion: ( x**2 + y**2 )/(4*.023) and high-beam headlamp reflector focus=19mm. Formula from here. Sounds like overkill, but I only achieved nice reflection with parabolic reflector with focus on centre of bulb.

Headlights rendered

Headlight baked textures, improved front air intake shape, added wings and molding below. Textures baked in Blender according to tutorial by Gamedev Fred.

Taillight rendered

Taillight baked textures, engine bay vent grille baked textures, exhaust.

More streamlined external mirrors.

Brake calipers (different front and rear according to disc size).

Quote from versiu :

Maybe make two internal mirrors as one subobject?

This is shown in the third scheme — neither mesh nor mapping rotates towards "eyes" because mirrors median point and "eyes" are in center (X=0).

Quote from Egor K :

Using united "internal mirror" subobject (doesn't matter build mirrored or not, or using flipped opposite side cutout or not).

I've tried manually rotating both mesh and mapping towards "eyes" to look backwards, but this doesn't change anything — in mirrors you see side windows.

Mirrors special placement problem Car has two internal mirrors and two external mirrors: four mirrors total, but LFS support only three: two external and one internal, which have to be centered.

Using two separate "internal mirror" subobjects, mapped with different cutouts (doesn't matter cutout flipped or not) — mappings rotated along Z together with last subobject towards "eyes".


After removing left "internal mirror" subobject, mapping rotated, same as before, but in the opposite direction.


Using united "internal mirror" subobject (doesn't matter build mirrored or not, or using flipped opposite side cutout or not).


Changing internal mirrors subobject to "attachment" (two external mirrors already mapped) leads to all mirrors turn black (doesn't matter build mirrored or not, or using flipped opposite side cutout or not).

After removing mappings from external mirrors, internal works like this:


Сonsidering central seating position, default POV=90deg, vehicle width, looking straight you can't see external mirrors, it makes sense to stick with last scheme for a while.

Last edited by Egor K, Wed, 16 Nov 2022 19:40. Reason : couple minor fixes

I use to have agang exe 24 (2011) street MTB and want recreate it inside LFS.
Who knows maybe LFS someday will support bunnyhop or at least hop (like GTA:SA does).

Engine

I figured that way:
Crank arm length = 0.175m
Rider mass = 70kg
Hand power (pulling handlebar) = 30kg
therefore
Rider force on pedal = (70+30)kg*9.8=980N
Engine moment = 980N*0.175m=171.5N*m
Since model mass (with rider) exceeds actual mass (due to: motor 26 kg, battery 7kg, wheels 19kg) I decided to set 152% torque.
IRL 12.3kg bike plus 70kg rider = 82.3kg
LFS 55.0kg bike plus 70kg rider = 125.0kg (152%)

Final Drive

Bike has 25 tooth front and 11 tooth rear sprocket, so 0.44 gear ratio. Since LFS allows 0.50 minimum, compensate with final drive ratio of 0.88.

Dimensions

According to dimensions from agang 2011 catalog (46.2 MB) (page 63/80):

Mesh

Current progress:


At first I thought to do it quickly, but got a little bogged down in the details

Quote from Flame CZE :

Ah yes, my bad. The way is to select all triangles and then click “select connected points”, then hide those.

Thank you!

Quote from Benzinass :

How to load LOD2 from file? when I try to load with LOD2 selected the the main object just gets replaced.

1 Load *.obj with lod2 (it will replace everything and became main object)
2 Save that main object from Modeller (mesh editor)

3 Load whole Vehicle again
4 Place triangles from main object to any other than first layer (must be empty)
5 Add "new subobject"
6 Load saved subobject from (2) by subobject > load

7 "merge into main"
8 Go to main object and select all triangles from first layer (that's why in (4) you need clean first layer - former subobject moved to it and now it's easy to select only lod2 triangles)
9 "add to : lod2"
10 remove lod2 tris from lod1

No matter which lod I choose, Modeller always shows all the points. Thus, regardless of the active lod "A: all" selects literally everything

A couple of workflow tricks.

While working on external shape to see clearly how adjust shape put marks, such as windows, doors, headlights, etc. by projecting NURBS curves:

Later, these contours were used to build the final mesh:
1 draw nurbs curve
2 add Shrinkwrap modifier (wrap method: Project, select Axis, allow Negative direction as curve is outside)
3 choose curve resolution (object data properties > Resolution Preview)
4 convert curve to mesh (check keep original)
5 join (Ctlr+J) converted curve to the final mesh

Since back of air duct meant to fit smoothly into external shape, I applied Lattice modifier to its part.

Image source: https://cars.mclaren.com/us-en/legacy/mclaren-f1

Triangle mode shows tris only from selected lod. But point mode shows vertices from all three lods.

Spoiler - click to reveal

This not only confuses work, also changing one lod leads to changing another, for example: duplicate triangles from lod2 to lod3 > using "fuse to green" to reduce lod3 tris = points from lod3 and lod2 fused synchronously. How to make visible and selectable points only from current lod?

SOLVED by Flame CZE

Last edited by Egor K, Wed, 19 Oct 2022 17:05. Reason : Problem solved

Thank you guys! Some progress in the following sequence:
1 external shape
2 external shape mesh + SubD
3 semifinal mesh + Subd
4 check
5 after shrinkwrap (3) to mesh (1)
6 final mesh
7 final

Last edited by Egor K, Thu, 12 Jan 2023 13:20. Reason : rearranged images