Vehicles have started to be equipped with multiple cameras, radars, parking sensors, etc.
Sensors information shall be represented efficiently in a non-distractive way to the driver.

Nowadays, the drivers are usually well isolated from sounds of the outside world. Well enough - for my innovation.

Background of the invention:

Once I drove alone in the very thick fog. It was very quiet outside. To help me avoid the hedges, I carefully adjusted the front windows so I could hear my car noise sound reflected from the trees of the forest along the road. I could hear any clearances by changes in the pattern of reflected noise of my engine.

The idea:

Human brains are processing very well the sounds reflected at short distance as a way to avoid collision with objects, and here comes the idea of using carefully reproduced natural sounds as a sensory information channel.

My idea isn't related to echolocation only: the information may arrive from radar, an infrared camera, etc.

It is reproducing the reflected sounds at the heart of my innovation.

Justification:

It is very important to avoid distracting drivers visually and audibly (beeping warnings are very distracting!). Using my invention, a driver's vision can stay extremely focused on the road
and acoustic channel in surround sound mode may tell objects kind, distance and direction,
by recreating natural sounds familiar to driver, for the best balance of comfort and attention.

Implementation:

To create surround sound in the vehicle, I would use car seat head restraint speakers. This sounds like a well controlled location, not distracting the vehicle's other passengers and limiting drivers' distraction by other sounds coming from the cabin and from the outside. Speakers volume has to adapt to the noise level.

The idea applies to collision avoidance with:
Ground vehicles:
...objects in blind spots, lane departure, fog, parking manueuvers
Airplanes:
...objects and ground clearance in heavy fog landing

The idea relates to the safety category by:
...helping to avoid collisions
...limiting a driver's distractions by unnecessary beeps/displays
...providing sensory comfort by reproducing natural sounds