A new approach to measure distance based on parallax

cncuong

Assuming I am looking down to the street, I can see the cars are coming to me. The floor of a car is farther than its top so it is moving slower.

My question is: based on the difference between the velocities of the floor and the top of a car, can we estimate the height of that car ?

I assumed that the ground is a plane and the top of a car is another plane, so measuring the distance between two planes is my point of view, which is measuring the height of the car.

evanh

Floor and roof will be same speed. If not then it would be very impressive acrobatics for a car.

Heater.

The question is not at all clear.

I imagine the idea is that we are a few floors up in some building watching cars the street below.

In that case the top of the car is closer to us than the floor. The floor and roof will have different angular velocity w.r.t. us as the car passes.

The angular velocity of the cars floor will be slower than the roor. So yes, one could indeed estimate the height of the car by measuring the angular velocities. Given that we know how high up we are from the road.

As you imply, evanh, the car would be doing some rotating if it's floor and roof had different speeds. That is exactly what happens as the car passes, it rotates with respect to us!

lardom

Trigonometry will give you the answer.

erco

Image grows at a mathematical rate as it approaches. What you do with that info is up to you.

Title says "measure distance", but your question is about estimating the car's height. Further, you intermix distance and velocity, so it's unclear what you are after.

Yes, Parallax the company is great. And yes, the parallax effect works great in Sharp distance sensors.

evanh

Ouch! That'll be Smile distance measuring at any significant distance. The further away the car is, the higher your sensor elevation would want to be.

It could work a lot better as an overhead, as the car passes by, speed measure I suspect.