An artificial finger designed to simulate human fabric evaluation could help apparel manufacturers obtain objective fabric ratings.

Whether choosing high-quality cotton sheets or determining if a fine linen shirt is worth the price, consumers historically have evaluated fabric hand based on subjective physical contact. But Seshadri S "Ram" Ramkumar, PhD, a researcher at Texas Tech University's International Textile Center, is hoping to change all that with the touch of a finger.

Ramkumar has developed an artificial polymeric finger, a device which not only simulates the way fabric is felt with the human hand, but also assigns a standard measurement to each fabric. The system was created in hopes of providing a faster and more accurate method of evaluating aesthetics than human touch or other established industry methods.

"When a consumer goes into a store, they may rub a jacket or sweater between their fingers to decide its quality. The problem is the finger test is not very accurate," Ramkumar said.

Common standard
Running fabric between the finger and thumb of an evaluator's hand - a time-consuming and costly test for manufacturers - is the most common standard for measuring the quality, or hand, of a fabric, Ramkumar notes.

Other fabric testing methods, such as the Kawabata Evaluation System for Fabrics (KES-F) and the Fabric Assurance by Simple Testing (FAST) method measure some hand-related properties, but many apparel companies complain that these testing methods are still costly, cumbersome and time-consuming.

"[My solution] is to create an industry-wide rating system for fabric, similar to the one currently used with cotton fiber. That way, consumers will know whether garments made of two fabrics that feel completely different are of similar quality," Ramkumar explained.

After initiating the project while at the School of Textile Industries, University of Leeds, England, Ramkumar collaborated with Dr David Wood and Katherine Fox of the Division of Restorative Dentistry, Leeds Dental Institute, to create the original prototype of the artificial finger, which measures the frictional properties of fabric.

Electronic signal
Describing how the device works, Ramkumar explained that the polymeric finger, which is rubbed over the fabric, sends an electronic signal to a computer system, which is used to measure the friction properties. During the process, the material is placed on a small platform, and a pulley creates a back-and-forth motion. The polymeric finger touches the fabric where the nerve endings would meet in a human finger and then simulates what a human finger would feel.

In describing apparel industry applications for the polymeric finger, Ramkumar told Bobbin that he envisions manufacturers using the device to obtain objective ratings of fabrics that can be used in production planning. For example, the device could be used to quantify the characteristics imparted through enzyme applications. "This would be of immense importance to denim apparel manufacturers," he said.