Fixed Heel Point (FHP): Driver CAD accommodation model
The FHP: Driver CAD model is a parametric model that is intended to provide the composite boundaries representing the body of the defined target design population, including posture prediction. The boundaries defined include the seat adjustment range needed to reach vehicle controls and the resulting positions for the occupants’ helmet, eyes, torso, knees, legs, and shins. Clearances between the occupant and surrounding interior vehicle surfaces have been added per MIL-STD-1472G (e.g. head clearance required from head (helmet) to vehicle roof line and thigh clearance to the steering wheel). Direct vision zones and ground intercept have been added based on MIL-STD-1472G and SAE Recommended Practice J1050, Describing and Measuring the Driver’s Field of View, 2009.
This model is applicable to truck-like ground vehicles in which the driving controls include a fixed-position accelerator pedal and a steering wheel. The associated tools are also applicable to non-driver workstations equipped with adjustable seats that require the crew to interact with controls and displays using hands and horizontally directed vision.
Given that the primary vehicle input to the model is the nominal steering wheel position, the model can be applied as early as the concept phase of the vehicle thus ensuring ample opportunity to design the vehicle around the target design population. The model is also beneficial to vehicle upgrade efforts such as those involving the replacement of seats or the addition of new equipment near the driver and other crew members.