The latest advances in 3D technologies are revolutionizing the ability to measure the human body, and this is having a tremendous impact on the healthcare industry and in the development of healthcare products. For example, Japanese research company Unitika Garments Technology is using optical 3D scanning to measure the human body to research use of dimensional inspection for quality control of textile products. Optical 3D measurement produces data that cannot be gathered using traditional methods.

The company's goals include verifying the hygiene level of the tested products, performing chemical and bacteriological analysis, and assessing the product's impact on the human body, including the differences between the amount of swelling when using various materials. In particular, the company wanted to verify the effectiveness of its client's compression socks and assess their specific effect on the body and the degree to which they could reduce leg swelling. However, during the project, the company was unable to sufficiently determine the daily level of a patient's leg swelling and whether the socks were able to reduce their swelling. The researchers found that traditional measurement methods did not provide the needed dimensions to compare the amount of swelling before and after wearing the socks. Measurements obtained by calculating water displacement turned out to be too imprecise due to the barely discernible level of the swelling in the legs.

To address the issue, Unitika used an optical metrology system from SmartTech3D, Warsaw, Poland. The scan3Dmed system, which is factory calibrated, is a metrologically certified device that enables researchers to obtain precise data in color by projecting strips of light onto the measured object. The cloud of points that represent the scanned surface has an accuracy of up to 0.01 mm. Because the system's measurement method is based on white LED structured light, there is no laser or physical contact involved so the entire process is safe for use on a patient's skin. In addition, the large volume of the device allows researchers to precisely measure the entire body — legs, arms, chest, and face. Scanning time is less than 0.7 seconds, which reduces the effect that a patient's respiratory system has on the results.

Fig. 1 - 3D scanning using a rotary stage.

By retaining the saved source data, the company was also able to conduct future additional analysis without the participation of volunteers, which reduced not only costs, but also time.

Case Study: Introduction

Unitika Garments Technology conducts research in the field of dimensional inspection and quality control of textile and plastic products in accordance with ISO/IEC 17025 standards. The company's research produces reports that are designed to not only improve the comfort of textiles, but also to optimize production costs. It uses the latest methods to analyze and assess the changes that take place in the body when the body is in contact with various materials. The company's research focuses on the following areas:

  • Textile product quality performance, measurement assessment.

  • Measurement assessment of safety and hygiene functions.

  • Chemical analysis, optical/electron micrography.

  • Assessment of comfort and functionality.

  • Human physiology measurement.

The Problem

When assessing human physiology, it is sometimes necessary to make calculations related to the body, such as measuring of the human face before and after some sort of treatment or measuring a person's waist before and after wearing a belt. For this case study, the calculation needed was a measurement of a person's leg swelling in order to verify the influence of a compression sock on the swelling.

Initially using traditional measurement methods, Unitika asked volunteers to avoid wearing socks all day so that it could then measure the natural level of swelling. The test was then repeated with volunteers wearing a compression sock. Measurements were taken in the morning and in the evening. The researchers measured the volume of the legs using a container with water to calculate the volume based on the filling.

Fig. 2 - Volume measurement by S3DM.

It was quickly apparent that it was extremely difficult to calculate swelling in this way, because the amount of leg swelling is too small to obtain an accurate measurement. Modifications made to the assess functionality of a textile product also made obtaining measurements difficult. In many cases, such modifications were imperceptible when using traditional methods. For these reasons, the study required a more accurate and precise metrology system. In addition to providing accurate measurements, the system needed to be capable of determining the influence of individual textile products on the leg swelling at a particular measuring point.

3D Measurement and Assessment

For measurement, the researchers used an optical 3D scanner operating in structural light technology. The device obtains precise data in color by projecting stripes of light on the measured object. In addition, the device instantly detects markers, thus meeting the requirements regarding the determination of the measuring point.

Table 1. Volume measurement results. Target: Four people.

In addition, because the scan3Dmed system measures a large volume (800 × 60 × 350 mm), it allowed researchers to measure not only the legs, but also the arms and chest. Because of the system's rapid measurement time, the team was able to minimize the impact of the patient's respiratory system on the measurement. In addition, the system's SMARTTECH3Dmeasure software and a dedicated rotary stage enabled the measurements to be automated (see Figure 1).

Data Processing

Fig. 3 - Calf measurement of morning with no swelling (left) and evening with swelling (right).

The 3D scanner and software were sufficient to carry out all of the research needed for the study and generate a report that could be presented to the customer. The system provided all of the results necessary to conclude the tests (see Figures 2 and 3) and obtain required data. As shown in Table 1, the volunteer's natural daily leg swelling increases its volume by 2 percent from 10 am to 4 pm when wearing no socks. When looking at the effect of the compression socks on the swelling, the Type B sock was determined to maintain the volume of leg swelling throughout the day, whereas compression sock Type A reduced the swelling by 2 percent compared with the subject's original condition. In addition, as shown in Figure 4, software added to the optical 3D scanner allowed the researchers to measure the diameter of the perimeter of the leg at rest for further investigation later.

Fig. 4 - Leg radius data.

Conclusion

Advances in optical 3D technologies are greatly improving measurement of the human body to aid in research and in the development of products for treatment. For Unitika, the 3D scanning technology enabled it to assess the product's impact on the human body, including the differences between the amount of swelling when using various materials for the compression socks.

The analysis not only made it possible to evaluate the effectiveness of the client's textile products, but the system also collected a lot of additional data. And because the system could store the 3D models, the researchers were able to conduct further analysis without re-engaging volunteers, thus reducing costs and time.

This article was written by Andrew Ostrowski, Marketing Manager for SmartTech3D, Warsaw, Poland. For more information, Click Here.