Unity *scaleable* raycasting car/physics very realistic -- 3

Dear Sirs or Madams, i need to have a raycast based vehicle physics-model which acts very very realistic, while the whole vehicle is scalable in the parent root (scale factor x/y/z). The full behaviour and feeling must be remain the same at every scale-size! That is the most important point. The car should act/feel very realistic at jumps, drifts, slides, breaking, while driving over bumps and jumps. Please check out this example movies to get a good base for this: Raycast-based vehicle with suspension and different surfaces: [login to view URL] Raycast suspensions: [login to view URL] Tilt/Flips: [login to view URL] ***Technical requirements, which must be 100% fullfilled*** - use Unity 2019 LTS - in EVERY case the vehicle must be scaleable without changing physics behaviour (the car should act with scale size 0.5 exactly the same like scale size 2,33 or 5, or whatever) - integrate a scale-slider in HUD to test the effect which scales the car at runtime - use a rectangle collider with rigidbody as physics - provide different car-setup variables in inspector to adjust the physics and change car-behaviour following the car-type (truck, kart, drift-car, f1-car, etc) - the 4 raycasts to the ground should detect different surfaces (please use a very simple version, just to see different behaviours according to physics-settings. For example: a car on grass got less forward+side traction) The hierarchy should be like that: - CarRoot (root element for scaling) -- Audio (empty) -- Physics (rectangle collider+rigibody) -- Visuals (meshes, etc.) ***Car settings*** - the distance of 2 axes (length+wide) of the vehicle must be changable to get different behaviours (for example: a very very thin vehicle could be a motorcycle, a very big vehicle with high suspesions-settings could be a monster-truck) - accelleration / braking settings - 2wd (front/rear) / 4fwd settings - suspensions settings must be available (strength, stiffness, length, etc) - dampened springs (Hooke's law) - forward/side/... traction settings must be available - maybe slip setting must be available - slope settings must be available - mass + gravity settings must be available - the center-of-mass should be adjustable ***Input*** - use classical/old input system ***Visuals*** - please use 3 different kind of visuals (f1 car, monster-truck, drift car) - the visuals should show a tilt/roll effect regarding the physics behaviour - the suspension should show a spring effect regarding the physics behaviour - the visual is in an extra hierarchy element which is synchronised to the physics-transforms Dont focus on visuals that much, the physics behaviour got priority! ***The final result should shown*** - a very realistic drift car (with bumps, jumps, drift, braking on sand, tarmac) - a feelable difference between 2wheel-drive (front) and 4 wheel-drive - if 2 cars collide, the collisions should shown nearly realistic (flips, turnovers, tilt sideways, etc) Focus on: realistic behaviour in every scale, realistic collisions, realistic feeling ***Paying and acceptance*** Id like to split this task in 3 milestones. Paying ONLY after a working/playable build to test the results. The split of milestones must be discussed.