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An automobile seat’s thermal performance can be challenging to quantify since it requires comprehensive human subject testing. Seat manufacturers must rely on subjective ratings to understand how the construction of a seat and its underlying heating and cooling technology may compare to other seats. Other factors may influence seat ratings published by global marketing information services companies (e.g., JD Power and Associates). In particular, occupants may be biased by the vehicle class in which a seat is installed and by how much the contribution of a specific vehicle’s HVAC system performance affects the perception of seat thermal comfort. Therefore, there is a need for an objective testing methodology that does not rely on human participants but is still capable of producing a thermal performance rating in terms of established thermal comfort scales.

A test protocol previously developed for automotive applications was adapted to evaluate the performance of a climate control system for a heavy-duty truck. Human subjects, as well as a test system composed of a high-resolution passive sensor manikin and a human thermal model, were employed to evaluate thermal comfort perception. Testing was performed in a climate-controlled wind tunnel equipped with a dynamometer. The truck’s HVAC system performance was evaluated in a −10 °C environment. Additionally, the test protocol was designed to explore a large range of thermal sensation and comfort states. Subjective responses, including thermal sensation and comfort, as well as thermo-physiological state information, quantified by skin temperatures measured across the body, were obtained from the human test participants and compared to that which was indicated by the test system.