Ideal Occupant Positioning Through Virtual H-Point Simulation

The optimal seating position in a vehicle is critical to the ergonomics, comfort, and safety of the occupants. CASIMIR/Automotive supports this process through precise H-point and backset simulations, enabling accurate analysis and adjustments already during the early development phase.

Importance of the eating Reference Point (SgRP) in seat design

In seat design, the Seating Reference Point (SgRP) is initially established. This point serves as a reference for the occupant's position in the vehicle and forms the anchor for the entire interior design. The SgRP is the basis for the ergonomic layout of the vehicle interior and the positioning of all relevant control elements and safety systems. A seat is designed so that, starting from this point, the occupant can reach all key components, while sitting securely and comfortably. The SgRP is surrounded by a tolerance zone, within which the measured H-point (hip point) must fall to meet ergonomic and safety requirements.

Early alignment of the H-point with the SgRP

Our simulation methodology precisely determines the deviation between the H-point and the SgRP early in the development phase. The seat model from the static comfort simulation is combined with a H-point manikin model based on the SAE J826 standard. This approach delivers predictions that deviate only by a few millimeters from later prototype measurements. Thanks to this accuracy, measures can be developed and implemented during the virtual development phase to bring the H-point closer to the SgRP. This improves both ergonomics and comfort for the occupant while reducing the need for costly modifications in later development stages.

Backset simulation for determining headrest spacing

In addition to H-point simulation, we use the Head Restraint Measuring Device (HRMD) according to FMVSS TP 202a to determine headrest spacing (backset). This simulation is conducted in line with the prescribed testing procedures, allowing for precise measurement of the distance between the head and headrest. An optimal backset is essential for occupant safety, especially in rear-end collisions, as it minimizes the risk of cervical vertebra injuries.