Tuning Into the Symphony of Road Noise

July 12, 2023

When it comes to immersive driving experiences in simulators the devil is in the details. Even the road’s texture from smoothly paved highways to bumpy off-road trails should not only reflect visually but should also echo in the haptic feedback. In this context it might seem puzzling: how can we convert the jargon of suspension data into the language of haptics?

Decoding Standard Deviation

Standard deviation is a measure of the amount of variance or dispersion in a set of values. In our context the “set of values” refers to the audio signals generated due to the interaction between tires and different road surfaces.

A low standard deviation indicates that the values tend to be close to the mean (or expected value) which translates to a smooth less noisy road in our simulator. On the other hand a high standard deviation indicates that the values are spread out over a wider range implying a bumpy noisy road.

Mapping Noise to a [0,1] Range

To convert the calculated standard deviation into a quantifiable noise factor within a range of [0,1], we compare it to a predetermined maximum noise value. For instance if we define the maximum tolerable road noise as MaxNoise, any calculated standard deviation (SD) can be normalized to a value between 0 and 1 by simply dividing SD by MaxNoise.

To illustrate let’s say the MaxNoise is 10 units and the calculated standard deviation for a particular road surface is 4 units. The noise factor for this road will be 4/10 = 0.4, a moderately smooth road.

It’s important to note that MaxNoise should be a reasonably high value to accommodate even the most extreme road surfaces. However it should also not be unrealistically high as that could result in most roads seeming smoother than they actually are.

The noise value then becomes a versatile input that can be plugged into the a haptic feedback system to adjust the vibration effects dynamically based on the real-time road conditions, contributing to a more immersive experience.

In essence the standard deviation does more than just crunching numbers. It acts as a bridge between the physical attributes of the virtual driving terrain and the sensation of the driver. Bringing an added layer of realism to the simulation. So buckle up and tune into the symphony of road noise.