Evaluation of Supporting Properties of Mattress Materials

Author: Synwin–Custom Mattress

The contact state between the mattress and the human body will affect the perceived comfort of the human body and further affect the quality of sleep. It is more likely to be the direct cause of pressure ulcers for long-term bedridden patients. In 1998, Peter and Avalino [1] studied mattresses using human body pressure test and subjective evaluation of comfort, and the results showed that the tested mattresses had better comfort than incompressible plank surfaces. In 1988, Shelton[2] proposed a pressure index (Pindex) through a large number of data analysis when synthesizing the average pressure average, pressure peak, pressure peak magnitude and other factors, and compared it with the mattress decompression test effect, showing a very good performance. good consistency.

In 2000, Defloor[3] conducted a study on the influence of different sleeping positions on the mattress pressure. The study showed that the 30° semi-sitting position and the prone position had the smallest pressure on the mattress contact surface, while the 90° side lying position had the lowest pressure on the mattress. The largest, which was also found to use a standard foam mattress, reduced interface pressure by 20 to 30 percent. In 2000, Bader [4] conducted a study on the relationship between sleep quality and bed surface hardness, and found that more people were better able to adapt to a softer mattress than a firmer mattress. In 2010, Jacobson et al. [5] conducted a study on patients with mild low back pain or stiffness. The study found that the human body contact interface during sleep has an impact on the quality of sleep. Replacing a medium-firm mattress can improve sleep discomfort and relieve the patient's waist. Back pain and stiffness.

In recent years, Chinese scholars have also increased their research on mattresses, and the main body is still reflected in the relationship between mattress comfort, sleep quality, mattress thickness, and material properties. In 2009, Li Li et al. [6-7] measured the body pressure distribution index of the human body by changing the thickness of the sponge on the surface of the mattress, and made a comprehensive subjective and objective analysis, and found that the thickness of the sponge has an important impact on the comfort of the mattress. In 2010, different types of sponge mattresses were selected, and the impact of sponge types on the overall and local comfort of the human body was analyzed and compared.

In 2014, when Hou Jianjun [8] studied the influence of mattress materials on the characteristics of the human body in the supine position, he found that the contact area between the mattress and the human body is large, and long-term contact can easily lead to human fatigue. It can be seen from the above that the research on mattresses mainly lies in the test of pressure distribution, and is also limited to certain materials. Objective evaluation methods for the support effect of mattress materials are relatively rare.

In this paper, 6 typical mattress materials are selected, and the compression test in the thickness direction and the human body pressure distribution test are carried out on them. The supporting effect of the mattress material. 1 Experimental method A healthy female college student was selected for the test. The subject had no history of musculoskeletal disease, was 24 years old, was 165 cm tall, and weighed 55 kg. The materials selected in this experiment are ordinary sponge, memory foam, vertical sponge, two different densities of spray foam and 3D material. The compression performance of mattress materials was tested using the American Instron-3365 material testing machine, which is mainly used for material tensioning. Elongation test.

In order to test the compression properties of mattress materials, a pair of specially made 10cm×10cm square iron plates were attached to the upper and lower chucks respectively to realize the compression test. The mattress material is cut into a cylinder with a diameter of 6.6mm, placed on the lower test plate, the upper iron plate slowly compresses the mattress material downward, and stops the compression when the thickness is 5mm, and records the pressure from the beginning of compression to the end of the experiment. . The body pressure distribution test adopts the dressing comfort test system of Japan AMI Company.

The device uses a balloon-type pressure sensor, which collects data every 0.1s during the test. For the body pressure distribution test, 6 parts of the seventh cervical vertebra, shoulder, back, leg, thigh and calf were selected for testing, and airbag sensors with a diameter of 20 mm were attached to each test point. The tester lies flat on the mattress, and when the pressure data becomes stable, the data is recorded for 2 minutes.