H-point

The H-point (or hip-point) is the theoretical, relative location of an occupant's hip: specifically the pivot point between the torso and upper leg portions of the body — as used in vehicle design, automotive design and vehicle regulation. The H-point can be measured relative to other features, e.g. h-point to vehicle floor (H30) or h-point to pavement (H5): a vehicle said to have a "high H-point" may have an H-point that is "high" relative to the vehicle floor, the road surface, or both.

Technically, the measurement uses the hip joint of a 50th percentile male occupant, viewed laterally, and is highly relevant to national and international vehicle design standards such as global technical regulations (GTR). For example, a vehicle design standard known as the Society of Automotive Engineers (SAE) J1100 Interior Measurement Index sets parameters for such measurements as H30 (H-point to vehicle floor); H5 (H-point to pavement surface), H61 (H-point to interior ceiling) and H25 (H-point to window sill).

As with the location of other automotive design "hard points," the H-point has major ramifications in the overall vehicle design, including roof height, aerodynamics, visibility (both within the vehicle and from the vehicle into traffic), seating comfort, driver fatigue, ease of entry and exit, interior packaging, safety, restraint and airbag design and collision performance. As an example, higher H-points can provide more legroom, both in the front and back seats.

By the early 2000s there had been a global trend toward higher H-points relative to the road surface and the vehicle's interior floor. Referring to the trend in a 2004 article, The Wall Street Journal noted an advantage: "the higher the H-Point, the higher you ride in the car, and in some cases, the more comfortable you feel behind the wheel".

Buses, minivans, SUVs and CUVs generally have higher H-points (relative to the road surface and the vehicle interior floor) than sedans, though certain sedans feature higher H-points than most, e.g., the Ford Five Hundred. Sports cars and vehicles with higher aerodynamic considerations, by contrast, may employ lower H-points relative to the road surface. When an automobile features progressively higher H-points at each successive seating row, the seating is called stadium seating, as in the Dodge Journey, and Ford Flex.

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