The Robotic arms project conducted by a group of DTU lecturers for two disabled children from Quang Nam helped reduce the daily hardships they faced at home and school. In the near future, the team will enhance the product esthetically, making it even more compact, in eye-catching colors and cheaper.
With his new robotic arm, Hieu was quickly able to grasp objects of varying sizes and weights independently (Photo: H.T)
The Robotica team at the DTU Center for Electricity and Electronics (CEE), which won a prize for the best hand-controlled robot and automatic robot in 2013, and a third place and a style prize in 2014, was founded with the enthusiastic support of a team of lecturers, including Mr. Dang Ngoc Sy, Dinh Huu Quang, Pham Quyen Anh, Dr. Ta Quoc Bao, from the Center for Advanced Chemistry, and originator, Ms. Thao, who used to work at the DTU Silver Swallows Studio. They quickly set to work creating robotic arms for disabled, needy students.
Phan Trong Hieu lives in Ai Nghia, in the Dai Loc district of Quang Nam. Four years ago, when he was tending the cattle, Hieu lost most of his right arm and part of his left one because of an unexploded bomb. After the accident, Hieu became shy and withdrawn. Not wanting to give up his studies, he and his mother had the idea of boring holes in a plastic pipe for him to write with. However, with the “new arms”, he can now ride a bicycle and do simple things, like pouring water and packing his own schoolbag.
The DTU Robot Arm team also donated a robotic arm to Tran Dang Khoa, a sixth-grader at the Nguyen Hue Junior High school in Dai Loc. Khoa was born without a left arm, which made him unconfident with others but Khoa’s parents were too poor to afford prosthetics. So they were jubilant when they heard their son shout out, “I have two hands now!”
The research group made several trips to Quang Nam to meet them and take accurate measurements. Hieu’s case was not congenital, so the measurements of his left and right arms were completely different and many adjustments were necessary.
The first version of the robotic arms was only 50% successful but, by the third version, were much improved. After being fitted with their robotic arms, the children could grasp objects, and pour and drink water. Hieu could even ride a bicycle with them.
In addition to the basic materials, including plastic wire, non-stretch zippers, absorbent padding and durable fasteners, DTU also needed to invest in two visible-light technology plastic 3D printers to fashion the prosthetic arms. The CEE manufactured two thermoplastic 3D printers to simulate the details, with high accuracy and durability. To produce an arm that could simulate the human arm, the Robotica group had to design the minute details of the fingers, hands, arms, joints and muscles in 3D using the Solidworks software application before printing in 3D. The printing took much time, on average six hours, while some needing up to fifteen. For accuracy, they had to repeatedly compute the stresses and the most suitable shapes to fit the length of the arm of each child.
After readjusting the parameters twice, the robotic arms became more compact, light, esthetic and allowed the users to grasp objects of different sizes and weights. Dang Ngoc Sy believes that, to create an economical robotic arm, the development team must master the technology and locate the necessary materials, the plastic wire, non-stretch zippers, absorbent padding, durable fasteners and so on. Every detail, fingers, hand, arms, joints and muscles must have its parameters computed to fit what the children have left of their injured arms.
After the success of their second version, the Robotica team continues to construct a third version for different types of other disabilities. “Our objective is to provide for the disabled from 10 to 25 years- old,” said Mr. Sy. “In the future, we will enhance the product esthetically, making it even more compact, in eye-catching colors. One of the most important goals is to establish self-confidence and comfort when children use the robotic arms.”
The research group is also planning to upgrade the robotic arms to integrate sensors that can receive signals from the central nervous system and control muscle movement, making things even easier for the users.
(Media Center)