Four Wheel Drive Optimal Landing Angle

[jonjonz]

Which will produce consistently faster lap times, when landing a 4 wheel drive race car at speed:

- front wheels first
- rear wheels first
- front and back simultaneously

Given a 4 wheel drive race vehicle traveling at racing speed, suspended in the air, after driving off a jump or drop off, is there an optimal angle of the longitudinal plane in relation to the ground when the vehicle lands.

Variables include longitudinal rotation, and the horizontal angle of the plane the vehicle is landing on in relation to the direction of the vehicle.

My personal observations using a simulator running a course with multiple jumps is that landing front wheels first provides the fastest lap times while landing rear wheels first produces slower lap times. Landing both ends simultaneously seemed to be faster than rear wheels, but slower than front wheel landings.

Is there a physics based reason for this, or is my observation caused by something inherent in the design of the simulation.

 

[berkeman]

Which will produce consistently faster lap times, when landing a 4 wheel drive race car at speed:

- front wheels first
- rear wheels first
- front and back simultaneously

Given a 4 wheel drive race vehicle traveling at racing speed, suspended in the air, after driving off a jump or drop off, is there an optimal angle of the longitudinal plane in relation to the ground when the vehicle lands.

Variables include longitudinal rotation, and the horizontal angle of the plane the vehicle is landing on in relation to the direction of the vehicle.

My personal observations using a simulator running a course with multiple jumps is that landing front wheels first provides the fastest lap times while landing rear wheels first produces slower lap times. Landing both ends simultaneously seemed to be faster than rear wheels, but slower than front wheel landings.

Is there a physics based reason for this, or is my observation caused by something inherent in the design of the simulation.

Welcome to the PF.

It probably has less to do with the landing and more to do with the takeoff. I don't think 4WD race vehicles have anywhere near the attitude control in the air as motocross bikes. For MX bikes, you can optimize your takeoff and then adjust your attitude in the air to land evenly with the power on. With a 4WD race car, I'd expect them to leave the jump wide open, and just deal with however that makes them land. Are you taking off differently in your simulations?

 

[king_me]

Well let’s break it down…Landing on 4 wheels…

-less compression/rebound on 4 shocks = vehicle levels out faster
-more wheels on the ground = more torque transferred
-all tiers on the ground or in the airLanding on front wheels…

-more compression/rebound on 2 shocks = more bounce
-truck can “pull” itself
-truck will ‘teeter totter’ (bounce up/down - front/back wheels)Landing on rear wheels…

-more compression/rebound on 2 shocks = more bounce
-truck can “push” itself
-truck will ‘teeter totter’Now…

What is the amount of time the wheels are off the ground in the 3 categories?
What’s ideal, “pulling or Pushing” (remember the front of the vehicle 60-75%? of the weight (estimation))You could ask a bunch more questions but let’s keep it simple for now and get a base before we proceed. I can now see why landing on the front may be faster.-the car ‘fly’s’ over the hill
-lands on the front wheels
-all that weight being driven into the ground at some factor greater than the actual weight of the vehicle
-wheels spinning , getting superb traction
-car can “pull” itself from the front which seams better than pushing from the back (with less traction & steer ability in my opinion)
-as the car pulls itself forward it brings down the rear end to the ground
& even though its teeter tottering I believe the total lost time in ‘wheel to ait’ may be less than the 4 wheel bounce.Now your question is: What is the best angle to land the vehicle on the front wheels?Visually…. My guess is 3-5 degrees. Any more and you hit too hard, nose dive, bottom out & just plane out kill your momentum. Any less, your closer to landing all 4 wheels but hey… 1-3degrees could be the sweet spot?
Anybody agree with what was said? How much data are we going to need to calculate this little bugger?-total vehicle weight, weight distribution, wheel speed/traction, engine hp & torque, ground condition, hill, speed, air time, distance traveled in the air and what not…….