Alexis Noel, et al
The four phases of cat grooming - Top layer: Tongue extension, tongue lateral expansion, sweeping of the tongue through fur and lastly retraction of the tongue in a V-shape curl. Middle layer: Cat tongue spines when tissue is straight and curled. Bottom layer: Cat tongue mimic when silicone substrate is straight and curled.
A researcher from Georgia Tech has conducted an in-depth study into cat tongues using a 3D-printed model at 400% scale.
Alexis Noel, a doctoral candidate in mechanical engineering, was inspired to examine a cat’s tongue after watching her pet lick a thick, microfiber blanket and become stuck. Working in the Hu Biolocomotion Lab at Geogia tech, Noel decided to explore the ‘spines’ she noticed on her cat’s tongue while trying to separate it from the blanket. Cats tend to have backward-facing barbs on their tongue to make it easier for them to rasp the meat from bones of their prey.
“When the cat’s tongue hits a snag, it pulls on the hooks, which rotate to penetrate the snag even further,” explains Noel. “Like a heat-seeking missile for snags, the hook’s mobility allows the cat to better tease tangles apart.”
Noel likens this concept to using different types of hairbrush. She has been discussing what the concept might enable for more practical human applications, at the 69th Annual Meeting of the American Physical Society’s Division of Fluid Dynamics (DFD), between November 20th and 22nd in Portland, Oregon.
“A typical hairbrush has spines that stick straight out. When hair collects on the brush it forms a thick mat that must be removed by hand,” Noel said. “In comparison, the cat’s flexible spines make it easier to clean. When not in use, the spines on a cat tongue lie nearly flat against its surface, like overlapping shingles. This configuration provides openings in a single direction, enabling the mat of hair around the bristles to be removed with a single finger swipe. These openings face the cat’s throat and are also why cats swallow their hair and end up with hairballs.”
The concept was examined in the lad using macro- and high-speed videography equipment. Noel was able to zoom in and observe the unique shape and flexibility of the tongue spines during grooming. The tongue mimic was printed at four times its actual size to allow the researchers to sufficiently explore their theories.
“[We found] both the cat tongue and mimic are very good at cleaning and removing tangles in fur samples,” Noel said. “We also discovered that the cat tongue is self-cleaning. It’s easy to remove hair beneath the spines by simply brushing the tongue from tip to end.”
This may ultimately affect soft robotics technologies as they struggle to find ways for soft materials to grip surfaces.
“The cat tongue is flexible, but it can pull apart tangles in fur,” Noel added. “So we’re trying to develop a cat tongue-inspired surface based on our 3D-printed mimic. The flexibility of cats’ tongue spines may have broad-reaching applications from an easy-to-clean hairbrush to wound cleaning within the medial field.”
Moving forward, Noel and her group of researchers want to explore the spacing of cat tongue spines and how that affects frictional resistance. They want to use this knowledge to develop a hairbrush suitable for human grooming, before going on to study the tongues of larger species in the cat family.
Currently, Noel is planning to develop the cat tongue mimic technology through the Innovation Corps at Georgia Tech and communicate with consumers, beauty and medical specialists around the US about application opportunities. She intends to file a patent within the next year, having already submitted a technology disclosure form.
