Car H-point Explained

 

In vehicle design and especially automotive design, 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, either relative to the floor of the vehicleor relative to the height above pavement level—and pertinent to seating comfort, visibility from the vehicle into traffic and other design factors. Technically, the measurement uses the hip joint of a 50th percentile male occupant, viewed laterally.

As with the location of other automotive design "hard points," the H-point has major ramifications in the overall design of a vehicle, including roof height, aerodynamics, visibility, comfort,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.

There has been a recent global trend toward higher H-points. 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 will generally have higher H-points 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. 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.

Vehicle interior ergonomics are integral to an automotive design education. The Society of Automotive Engineers (SAE) has adopted tools for vehicle design, including statistical models for predicting driver eye location and seat position as well as an H-point mannequin for measuring seats and interior package geometry. Occupant posture-prediction models are used in computer simulations and form the basis for Crash test dummy positioning.

Regulatory definition: For the purpose of U.S. regulation and GTR's (Global Technical Regulations) — and for clear communication in safety and seating design— the H-point is defined as the actual hip point of the seated crash test dummy itself, whereas the R-point (or SgRP, seating reference point) is the theoretical hip point used by manufacturers when designing a vehicle — and more specifically describes the relative location of the seated dummy's hip point, when the seat is set in the rearmost and lowermost seating position.