Tentacle-Like Prosthesis Offers Simple, Practical Design

Both aesthetically and functionally, Kaylene Kau’s prosthetic design is nothing like the human arm — for one thing, it is long, conical and stark white. The device’s interlocking concave segments allow it to curl in toward the body, then straighten again, without folding in on itself and swinging backward. It definitely does not resemble current devices coming to market

But that is okay with Kau.

  Kaylene Kau, an industrial design student created a prosthesis that is nothing like a human arm.
  Kaylene Kau, an industrial design student created a prosthesis that is nothing like a human arm.
  Images: Kaylene Kau

A recent industrial design graduate of the University of Washington in Seattle, Kau and her classmates had 10 weeks to research, create and build a prosthetic device. Magnus Feil, MFA, FH, her industrial design professor, told his students to push the boundaries of prosthetic design and ignore current trends within the profession, she said.

“A lot of things with potential have not been explored, simply because [the ideas have] been constrained,” Kau told O&P Business News.

Because the prosthetic market is so small, Feil felt that his students had the opportunity to design devices that could impact the industry. The class set to work on doing just that. Kau and her classmates spent a great deal of time during the first month of the project researching and experimenting — and pretending to be amputees.

“We taped our hands up, we restricted the use of our hands for a couple days,” Kau said. “We tried to figure out what the problem areas were and what we could do to improve [them].”

The students also received guidance from Joanne Tilley, someone with a vested interest in their success. Tilley, a transradial amputee and local artist at Lost Limb Studios, wanted to collaborate with design students to hear fresh ideas and perspectives different from those of medical personnel and engineers. She served as an adviser for the project, working closely with the students as they navigated through the creation process. Tilley visited the class, critiqued their designs and ideas, and gave them valuable insight into the issues that amputees face every day.

  This prosthesis is meant to be an assistant to the amputee’s dominant hand.
  This prosthesis is meant to be an assistant to the amputee’s dominant hand.
 

Members of the prosthetic industry, like prosthetists and others working to create simple devices for third world countries, also provided guidance.

As part of the assignment, Kau and her classmates were encouraged not to try to replicate the sound limb. For one thing, it would not be a cost-effective use of resources considering the complexity of the arm and hand. Further, Kau realized that the prosthesis did not have to replace the missing human hand — it merely had to replace the macroscopic function of the missing limb.

“If you have a hand that is functioning well, that becomes the hand you do all your fine motor skills with, like writing and those detail-oriented things. The prosthesis just acts as an assistant to the dominant hand,” she said. “I wanted to focus on that.”

The tentacle prosthesis was born of that premise. The curling motion accommodates a variety of tasks and offers more stability than a hook prosthesis in lifting objects as the device curls around them and brings their weight closer to the amputee’s body. The device was designed to have a simple motor in the base of the prosthesis, with a pulley system retracting and extending the arm. Currently, Kau envisions the control to be placed in a remote device or in buttons on the side of the device. She said she hopes to construct the prosthesis from carbon fiber, with an interior silicone grip.

Feil encouraged her to build upon the idea, since its unconventional nature would likely generate attention for her work. And it has. The device, which Kau simply calls “prosthetic,” has been dubbed the tentacle arm in various Internet stories, even though she actually did not use the word tentacle anywhere in her portfolio presentation of the device.

“That’s just what people see, and I totally understand,” she said.

Other members of the class also worked on simple, task-specific ideas for their prostheses. One student designed a prosthetic limb to help amputees regain function in the kitchen; another created an arm consisting of only a laser cut piece of plastic that costs $25 to make.

The design of the prosthesis needs more work, Kau admitted, as she neglected elements like the interface in favor of the design in the limited amount of time the class was provided.

“The main thing is that I wanted it to be versatile and intuitive,” she said. “There are also a lot of problems with that, I realized. There are a lot of small things that I want to work on.”

  The device curls in only one direction and brings an object closer to the body, offering the amputee better control.
  The device curls in only one direction and brings an object closer to the body, offering the amputee better control.
 

She said she also plans to add a joint on the terminal device, which would allow the amputee to shift the curling device 360·.

Although amputees have contacted her to provide positive feedback on her prosthetic design, she has not had any interest from manufacturers thus far since graduating from the program in June 2010.

Undeterred, she plans to finish the device as she had originally envisioned it. And to find a job in industrial design. — by Stephanie Z. Pavlou

Disclosure: Kaylene Kau has no relevant financial disclosures.

Both aesthetically and functionally, Kaylene Kau’s prosthetic design is nothing like the human arm — for one thing, it is long, conical and stark white. The device’s interlocking concave segments allow it to curl in toward the body, then straighten again, without folding in on itself and swinging backward. It definitely does not resemble current devices coming to market

But that is okay with Kau.

  Kaylene Kau, an industrial design student created a prosthesis that is nothing like a human arm.
  Kaylene Kau, an industrial design student created a prosthesis that is nothing like a human arm.
  Images: Kaylene Kau

A recent industrial design graduate of the University of Washington in Seattle, Kau and her classmates had 10 weeks to research, create and build a prosthetic device. Magnus Feil, MFA, FH, her industrial design professor, told his students to push the boundaries of prosthetic design and ignore current trends within the profession, she said.

“A lot of things with potential have not been explored, simply because [the ideas have] been constrained,” Kau told O&P Business News.

Because the prosthetic market is so small, Feil felt that his students had the opportunity to design devices that could impact the industry. The class set to work on doing just that. Kau and her classmates spent a great deal of time during the first month of the project researching and experimenting — and pretending to be amputees.

“We taped our hands up, we restricted the use of our hands for a couple days,” Kau said. “We tried to figure out what the problem areas were and what we could do to improve [them].”

The students also received guidance from Joanne Tilley, someone with a vested interest in their success. Tilley, a transradial amputee and local artist at Lost Limb Studios, wanted to collaborate with design students to hear fresh ideas and perspectives different from those of medical personnel and engineers. She served as an adviser for the project, working closely with the students as they navigated through the creation process. Tilley visited the class, critiqued their designs and ideas, and gave them valuable insight into the issues that amputees face every day.

  This prosthesis is meant to be an assistant to the amputee’s dominant hand.
  This prosthesis is meant to be an assistant to the amputee’s dominant hand.
 

Members of the prosthetic industry, like prosthetists and others working to create simple devices for third world countries, also provided guidance.

As part of the assignment, Kau and her classmates were encouraged not to try to replicate the sound limb. For one thing, it would not be a cost-effective use of resources considering the complexity of the arm and hand. Further, Kau realized that the prosthesis did not have to replace the missing human hand — it merely had to replace the macroscopic function of the missing limb.

“If you have a hand that is functioning well, that becomes the hand you do all your fine motor skills with, like writing and those detail-oriented things. The prosthesis just acts as an assistant to the dominant hand,” she said. “I wanted to focus on that.”

The tentacle prosthesis was born of that premise. The curling motion accommodates a variety of tasks and offers more stability than a hook prosthesis in lifting objects as the device curls around them and brings their weight closer to the amputee’s body. The device was designed to have a simple motor in the base of the prosthesis, with a pulley system retracting and extending the arm. Currently, Kau envisions the control to be placed in a remote device or in buttons on the side of the device. She said she hopes to construct the prosthesis from carbon fiber, with an interior silicone grip.

Feil encouraged her to build upon the idea, since its unconventional nature would likely generate attention for her work. And it has. The device, which Kau simply calls “prosthetic,” has been dubbed the tentacle arm in various Internet stories, even though she actually did not use the word tentacle anywhere in her portfolio presentation of the device.

“That’s just what people see, and I totally understand,” she said.

Other members of the class also worked on simple, task-specific ideas for their prostheses. One student designed a prosthetic limb to help amputees regain function in the kitchen; another created an arm consisting of only a laser cut piece of plastic that costs $25 to make.

The design of the prosthesis needs more work, Kau admitted, as she neglected elements like the interface in favor of the design in the limited amount of time the class was provided.

“The main thing is that I wanted it to be versatile and intuitive,” she said. “There are also a lot of problems with that, I realized. There are a lot of small things that I want to work on.”

  The device curls in only one direction and brings an object closer to the body, offering the amputee better control.
  The device curls in only one direction and brings an object closer to the body, offering the amputee better control.
 

She said she also plans to add a joint on the terminal device, which would allow the amputee to shift the curling device 360·.

Although amputees have contacted her to provide positive feedback on her prosthetic design, she has not had any interest from manufacturers thus far since graduating from the program in June 2010.

Undeterred, she plans to finish the device as she had originally envisioned it. And to find a job in industrial design. — by Stephanie Z. Pavlou

Disclosure: Kaylene Kau has no relevant financial disclosures.