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The NCSU sweating manikin system is a "Newton" type instrument designed to evaluate heat and moisture management properties of clothing systems. This life-sized manikin simulates heat and sweat production making it possible to assess the influence of clothing on the thermal comfort process for a given environment. Simultaneous heat and moisture transport through the clothing system, and variations in these properties over different parts of the body can be quantified.

The manikin consists of several features designed to work together to evaluate clothing comfort and/or heat stress. Housed in a climate-controlled chamber, the manikin surface is divided into 34 separate sections, each of which has its own sweating, heating, and temperature measuring system. With the exception of a small portion of the face, the whole manikin surface can continuously sweat.

Using a pump, preheated water is supplied from a reservoir located outside of the environmental chamber. An internal sweat control system distributes moisture to 139 "sweat glands" distributed across the surface of the manikin. Water supplied to the simulated sweat glands is controlled to a desired sweat rate set by the operator. A software-controlled routine individually calibrates each sweat gland and the calibration values are used to maintain the sweat rate of each body section.

Water exuding from each simulated sweat gland is absorbed by a custom made body suit. This specialty designed suit acts as the manikin’s ‘skin’ during sweating tests. It is form-fitted to the manikin to eliminate air gaps and provides wicking action to evenly distribute moisture across the entire manikin surface.

Continuous temperature control for the 34 body segments is accomplished by a process control unit that uses analog signal inputs from separate Resistance Temperature Detectors (RTDs). These evenly distributed RTDs are used instead of point sensors because they provide temperature measurements in a manner such that all areas are equally weighted. Distributed over an entire section, each RTD is embedded just below the surface and provides an average temperature for each section. Software establishes any discrepancy between temperature set point and the input signal, and adjusts power to section heaters as needed using a proportional-integral (PI) algorithm. Temperature controls are adjustable, by the operator, for each heater control.