Percussion instrument drums are traditionally made of wood, which is becoming less available as environmental concerns grow. In order to replace wood in percussion instruments, four types of epoxy resin composites reinforced with fabrics of hemp, flax, ramie, and jute, respectively, are fabricated using vacuum assisted resin infusion molding. The tensile and flexural properties of the composites are measured and compared with those of ailanthus wood. The results show that the flexural strengths and moduli of the composites are either better or in between to those of the horizontal and vertical strips of the wood. An acoustic test method is developed to test the acoustic performance of the composites and the wood. The results show that the composites have lower acoustic dynamic moduli, acoustic radiation damping coefficients, sound velocity, and higher acoustic impedance than those of the wood due to their lower flexural moduli and higher specific densities. The shapes of the acoustic spectra for the composites are somewhat similar to those of ailanthus. The acoustic performance comprehensive scores of the four composites are also in between those of the vertical and the horizontal strips of ailanthus. It is possible to match the acoustic performance of ailanthus by increasing the flexural modulus and decreasing the specific density of the composites through reducing the yarn crimp, increasing the fiber volume fraction, and introducing microvoids into the composites.

The hairy skin of the human body is the main receptor of fabric contact. In order to evaluate clothing comfort objectively, electroneurophysiological tests with nine subjects were carried out to determine their cognitive differences in fabric static and dynamic contact. Electroencephalography and electrocardiography signals were collected when the subjects statically and dynamically touched a piece of polyester fabric with their forearms. According to their electroneurophysiological responses to fabric contact, the subjects could be categorized into three different types, namely, extraordinary, ordinary and nonsensitive ones. Their different sensitivity could be observed from the activities of α waves, sympathetic nervous system and pneumogastric nervous system. The extraordinarily sensitive subject responded to the fabric–skin static contact with an intensive α rhythm reaction followed by a suppressed α wave, an enhanced activity of the sympathetic nervous system and a mild participation of the pneumogastric nervous system. During dynamic contact, the pneumogastric nervous system activity increased greatly to balance the nervous system. The ordinarily sensitive subjects responded gently to the fabric–skin static contact, with a gradually suppressed α wave, an enhanced activity of the sympathetic nervous system and the near absence of the pneumogastric nervous system. Fabric dynamic contact induced a strong α rhythm reaction followed by a suppressed α wave combined with a joint effort of the sympathetic nervous system and pneumogastric nervous system. The nonsensitive subjects responded with almost no difference between the fabric–skin static and dynamic contact in both electroencephalography and electrocardiography tests. This preliminary study could provide an efficient way to identify different types of subjects and lay a fair ground for comparison purposes in future electroneurophysiological studies of clothing comfort.

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