Statistics regarding amputees, discussed in the recently published ‘Functional evaluation of a non-assembly 3D-printed hand prosthesis’ are disturbing, as nearly 40 million people are in need of prosthetics today and only five to fifteen percent of them are granted the proper access and affordability necessary for replacement limbs.
While some modicum of healthcare may be accessible for patients in big cities of developing countries, those who live in more isolated areas may find transportation challenging—not to mention expenses all around. For those who attain healthcare, the chances of them returning for follow-up care are slim.
3D printing has been shown to offer positive benefits for healthcare in rural areas, from offering diagnostic devices often in the form of 3D printed smartphone attachments, for testing and treating of parasitic infections, cancer, malaria, and more. As for prosthetics, organizations like e-NABLE have also been behind the design and fabrication of countless prosthetic devices, often for children in need.
Relatively easy to master and affordable to purchase, 3D printers offer undeniable potential for developing countries; however, complex assembly could be an issue—leaving the researchers to design a prosthetic that can be fully printed. One of the most realistic scenarios involves the completion of 3D prints of prosthetics by servicers, allowing delivery to the end-user through local organized networks.
For this study, the researchers designed a prosthesis with the following features:
- Body powered control
- Cosmetic appearance
- Lightweight structure
- Water and dirt resistance
Each hand prosthetic is made up of four fingers and a thumb, with the fingers connected to the palm and then joined via a whippletree design.
“All fingers in motion are activated by a force transmission scheme which is made out of a main driving link, the whippletree arrangement, and the links that connect the four fingers,” explain the researchers. “The hand is actuated by a Bowden cable attached to the main driving link that is allowed to go on a linear motion following the movement of the cable.”
The leaf spring configuration consists of 3D printed plastic sheets that both bend and pull, driven by activation of the fingers.
“When the fingers are activated, the pulling forces drive the leaf springs to unbend and deform to a straight configuration,” explain the researchers. “As the leaf springs return and recover from the deformation, spring-like behavior is provided, combining actuation and a return spring in one non-assembly 3D printed element.
“In order to achieve non-assembly fabrication of the concept, a number of design guidelines were used using the advantages of 3D printing for design versatility while circumventing many of its shortcomings.”
Customized samples were printed on an Ultimaker 3, using PLA, testing the leaf spring and movement of the hand in five different experiments. The designs were tested using both the Box and Blocks Test (BBT) and the Southampton Hand Assessment Procedure (SHAP) test as 20 healthy students were enlisted from the Delft University of Technology to participate in the testing portion of the study, simulating use of the prosthetic.
The hand was fabricated with almost no assembly required—aside from the removal of supports and one ‘snap-fit step.’
“The hand achieves adaptive grasping even though it is made out of only two parts,” explained the researchers. “We argue that such a design and fabrication approach can increase accessibility of hand prostheses since easily accessible low-cost equipment (an Ultimaker 3 3D printer) was used together with low-cost material (PLA).”
There were some challenges, in the end, however, as the material for the leaf spring was deemed ‘not suitable’ for durability and reliability over the long term.
“… the 3D-printed hand evaluated in this study shows comparable performance with just a small friction enhancement on the finger pads. Yet, grasping and functionality can be improved by increasing the pinch force. Moreover, it is worth noting that most ADLs require low grip forces,” concluded the researchers.
“The non-assembly design achieved a comparable level of functionality with respect to other BP alternatives. Taking into consideration that most ADLs require low gripping forces and adding an increased accessibility provided by the advantages of the nonassembly and 3D printing approach, we consider this prosthetic hand a valuable option for people with arm defects in developing countries,” concluded the researchers.
What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.[Source / Images: ‘Functional evaluation of a non-assembly 3D-printed hand prosthesis’]
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Takwimu kuhusu watu waliokatwa viungo, zilizozungumziwa katika tathmini ya kazi ya prosthesis ya mkono iliyochapishwa kwa 3D isiyo ya mkusanyiko, ni ya kusumbua, kwani karibu watu milioni 40 wanahitaji prosthesis leo na asilimia tano hadi kumi na tano tu kati yao wanapewa upatikanaji sahihi na bei nafuu muhimu kwa viungo vya badala. Wakati baadhi modicum ya huduma za afya inaweza kuwa kupatikana kwa wagonjwa katika miji mikubwa ya nchi zinazoendelea, wale ambao wanaishi katika maeneo ya kutengwa zaidi wanaweza kupata usafiri changamoto - bila kutaja gharama zote kuzunguka. Kwa wale wanaopata huduma za afya, uwezekano wa kurudi kwa ajili ya utunzaji wa kufuatilia ni mdogo. 3D kuchapisha imekuwa kuonyesha faida nzuri kwa huduma za afya katika maeneo ya vijijini, kutoka kutoa vifaa vya utambuzi mara nyingi katika fomu ya 3D kuchapishwa smartphone viambatisho, kwa ajili ya kupima na kutibu maambukizi ya vimelea, kansa, malaria, na zaidi. Kwa upande wa vifaa vya kunyoosha, mashirika kama vile e-NABLE pia yamekuwa nyuma ya kubuni na utengenezaji wa vifaa vingi vya kunyoosha, mara nyingi kwa watoto wanaohitaji. Kwa kuwa ni rahisi sana kuitumia na bei nafuu kununua, printa za 3D hutoa uwezo usioweza kukataliwa kwa nchi zinazoendelea; hata hivyo, mkusanyiko tata unaweza kuwa suala - kuwaacha watafiti kubuni proteti ambayo inaweza kuchapishwa kikamilifu. Moja ya matukio ya kweli zaidi inahusisha kukamilika kwa uchapishaji wa 3D wa proteti na watunzaji, kuruhusu utoaji kwa mtumiaji wa mwisho kupitia mitandao ya ndani iliyoandaliwa. Kwa ajili ya utafiti huu, watafiti walibuni protesi na sifa zifuatazo: - Udhibiti wa nguvu ya mwili - Muonekano wa kifahari - Muundo mwepesi - Upinzani wa maji na uchafu - Kila protesi ya mkono inajumuisha vidole vinne na kidole gumba, na vidole vinavyounganishwa na kiganja na kisha kuunganishwa kupitia muundo wa whip. "Vipande vyote vya vidole vinavyoenda kwa mwendo huendeshwa na mfumo wa usambazaji wa nguvu ambao umefanyizwa na kiungo kikuu cha kuendesha, mpangilio wa whippletree, na viungo vinavyounganisha vidole vinne", wanaeleza watafiti. "Kikosi cha ""Bowden"" kinaweza kuendesha gari kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden, na kwa njia ya mstari wa Bowden." "Wakati vidole vinapoanzishwa, nguvu za kuvuta husababisha vijiti vya majani kuvunjika na kubadilika kuwa umbo la moja kwa moja", wanaeleza watafiti hao. Kama spring jani kurudi na kupona kutoka deformation, spring-kama tabia ni zinazotolewa, kuchanganya actuation na spring kurudi katika moja isiyo ya mkutano 3D kuchapishwa kipengele. "Kwa hivyo, ili kufikia utengenezaji usio wa mkusanyiko wa dhana, miongozo kadhaa ya muundo ilitumiwa kwa kutumia faida za uchapishaji wa 3D kwa ubunifu wa muundo wakati wa kuzunguka mapungufu yake mengi. sampuli zilizoboreshwa zilichapishwa kwenye Ultimaker 3, kwa kutumia PLA, kujaribu spring ya jani na harakati ya mkono katika majaribio matano matano.""" Kwa mfano, katika utafiti wa kwanza, wanafunzi 20 kutoka Chuo Kikuu cha Teknolojia cha Delft walipewa nafasi ya kushiriki katika sehemu ya majaribio ya utafiti huo, kuiga matumizi ya kinga. Mkono huo ulitengenezwa bila kukusanywa kabisa - mbali na kuondolewa kwa msaada na hatua moja ya "kufaa haraka". "Mkono huo hupata kukamata kwa kubadilika ingawa umetengenezwa kwa sehemu mbili tu", walieleza watafiti. "Kama ilivyoelezwa hapo juu, ""Mafunzo ya kubuni na utengenezaji yanaweza kuongeza upatikanaji wa vifaa vya mkono, kwa kuwa vifaa vya gharama nafuu vinavyoweza kupatikana kwa urahisi (mchapishaji wa Ultimaker 3D) vilitumiwa pamoja na vifaa vya gharama nafuu (PLA) "" - lakini kwa sababu vifaa vya spring ya jani vilionekana kuwa ""haifai"" kwa muda mrefu." "Kikosi cha 3D-printed Hands kilichopimwa katika utafiti huu kinaonyesha utendaji sawa na ""kuongeza kidogo tu kwa msuguano kwenye pads za vidole.""" Hata hivyo, uwezo wa kukamata na kufanya kazi unaweza kuboreshwa kwa kuongeza nguvu ya kukamata. Zaidi ya hayo, ni muhimu kutambua kwamba ADLs wengi zinahitaji nguvu ya kushikilia ya chini, <unk> walimalizia watafiti. <unk>The non-assembly kubuni mafanikio kiwango cha kulinganisha ya utendaji kuhusiana na mbadala nyingine BP. "Kukumbuka kwamba ADLs nyingi zinahitaji nguvu za kushikilia za chini na kuongeza upatikanaji ulioongezwa unaotolewa na faida za mbinu ya usanifu wa 3D na usanifu wa 3D, tunaona mkono huu wa prosthetic kuwa chaguo muhimu kwa watu wenye kasoro za mkono katika nchi zinazoendelea. """ Una maoni gani kuhusu habari hii? Tuambie maoni yako! Kujiunga na mazungumzo ya 3D-Printing katika 3DPrint.com """Kutumia 3D Printing kwa ajili ya utengenezaji wa vifaa vya 3D, ni muhimu sana kwa ajili ya utengenezaji wa vifaa vya 3D, kwa sababu kila kitu kinaweza kufanywa kwa njia ya 3D, na kwa njia ya 3D, kwa njia ya 3D, kwa njia ya 3D." Kuongeza 3D Models yako na kupata yao kuchapishwa haraka na kwa ufanisi.