The Science Behind Design for Ergonomics and Comfort Engineering

posted on - 2022-09-08

Vehicular ergonomics or ergonomics in general is defined by a set of parameters & math, the most important of which is the ‘H-point’. The H-point as you can see from the figure below is defined around the hip of a percentile manikin and its location is a standard constant. Vehicles are designed and built around the passengers for a number of logical reasons (some of which will be mentioned later) and the most crucial consideration is that of ‘passenger sizes’. Passenger sizes vary from continent to continent and also depend on the gender. Europe, USA, Japan passenger vehicles are designed based-on human size statistics gathered from census studies of their respective countries.

ergonomics,comfort, safety

The red here symbolizes the ubiquitous automotive term ‘H-point’

Percentiles are the chosen differentiation to cover a broad range of passenger size spectrum. For example, a 95 percentile manikin neglects 5% of the smallest female size and 5% of the largest male size, in other words, 90% of the human size population in that respective continent. A diagram showing various human sizes among males is shown below.

Male %ile (percentile) sizes for the U.S

Vehicles being designed inside out is one of the most fundamental aspects of vehicle design that define the safety of a vehicle. This fact would become even more widely-used to attain a fully crash safe vehicle in an era of self-driving autonomous vehicles.

Agricultural vehicles tend to accommodate larger human sizes, based on a very interesting study that farming equipment owners tend to be larger in size and weight as compared to an average passenger car owner. As shown below, a tractor seat occupies by its owner. Here again, H-point location plays a crucial role in the seating design of the tractor, right to the angle of the accelerator & the brake pedal, designed so as to appropriately absorb forces from the feet of the tractor driver.

H-point of a person sitting on a tractor is different from a racing car driver

An automatic vehicle recliner seat designed by us:

So intricate is the science of vehicle design these days that pedal positions for full tank, cruise drive, no fuel are defined during the R&D phase. One must assume that vehicle packaging will start to develop a whole new standard for EV & H-cell vehicles soon.