Posts Tagged 3D printing

[Abstract + References] Training of Hand Rehabilitation Using Low Cost Exoskeleton and Vision-Based Game Interface

Abstract

Motivating game-based training have the potential to improve therapy for people with neurological impairments. In recent years, the serious games have become extremely useful tools in rehabilitation field. They aim to stimulate the mobility of the body through an immersive experience that puts the user in interactive virtual environment. This paper is concerned about developing a customized augmented reality system for stroke rehabilitation. This will be done through integrating an interactive serious game interface with a hand exoskeleton device. This game-based rehabilitation system allows users to carry out physical rehabilitation therapies using a natural user interface based on Kinect’s skeletal tracking features and the electromyography (EMG) sensor. During game playing, the interactive user interface provides useful real-time feedback information such as the time required to grasp a desired dynamic virtual object, and the assigned score and thus the ability of the proposed system to provide a compensatory action regarding the dynamic behavior of the virtual target. The main goal of the developed virtual environment is to create positive influences on the rehabilitation process. Patient movement information and signals obtained from the developed exoskeleton device are used together to monitor the rehabilitation progress. The developed exoskeleton hand is a 3D printed low cost device suitable for grasping tasks that can be used even for domestic stroke patients. The developed exoskeleton device is not only a mechanical system able to perform the rehabilitation act but also it presents an effective tracking and traceability software solution. The EMG signals measured during hand motion are used to detect the intention of hand opening or closing which in turn will actuate the mechanical structure to accomplish the desired task. Parameters and results of patients’ exercises are stored and analyzed when needed to evaluate patients’ progress. The developed system is tested experimentally and it is able to restore the functions of the upper limb and mainly give patients more motivation to undergo the rehabilitation exercises.

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[Student thesis] Exoskeleton for hand rehabilitation – Full Text PDF

Abstract

This document presents the development of a first proposal prototype of a rehabilitation exoskeleton hand. The idea was to create a lighter, less complex and cheaper exoskeleton than the existing models in the market but efficient enough to carry out rehabilitation therapies.The methodology implemented consists of an initial literature review followed by data collection resulting in a pre-design in two dimensions using two different software packages, MUMSA and WinmecC. First, MUMSA provides the parameters data of the movement of the hand to be done accurately. With these parameters, the mechanisms of each finger are designed using WinmecC. Once the errors were solved and the mechanism was achieved, the 3D model was designed.The final result is presented in two printed 3D models with different materials. The models perform a great accurate level on the motion replica of the fingers by using rotary servos. The properties of the model can change depending on the used material. ABS material gives a flexible prototype, and PLA material does not achieve it. The use of distinct methods to print has a high importance on the difficulties of development throughout the entire process of production. Despite found difficulties in the production, the model was printed successfully, obtaining a compact, strong, lightweight and eco-friendly with the environment prototype.

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[WEB SITE] The future is now – Implications of 3D technology for orthoses | Lower Extremity Review Magazine

 

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2018 is shaping up as a breakthrough year for 3D printing in orthoses, as the industry moves from promise to reality. Experts agree: Three-dimensional printing will deliver custom clinical products, designed for individual patients at an affordable price.

By Keith Loria

3D printing is still a young technology for orthoses, and has great potential to change the way orthoses are designed and produced, say experts and specialists in the field.

The technology opens the possibility of adding value to the complete digitalization of analysis, design, and manufacture, said Blake Norquist, director of North American sales and business development for RS Print, a Paal-Beringen, Belgium–based company. He noted that combining digitized gait analysis and 3D printing may provide new standards and frameworks for experts based on objective, scientifically proven data.

One of the big game-changing aspects of this digitalization, Norquist noted, is the translation of data from objective analysis into a design that is then manufactured digitally. Expert involvement in the analysis and conversion toward design remains crucial, he said, adding, “[After] that point, the manufacturing becomes completely unbiased and reproducible.”

Gordon Styles, president and CEO of Star Rapid, a manufacturing company of 3D-printed medical applications based in Guangdong Province, People’s Republic of China, explained that 3D printing allows for orthoses manufacturers to respond quickly to requests for custom-made parts needed for rehabilitation. With this technology, he indicated, it is simple to create tailored supports, such as an insole, using high-resolution medical scans of a patient’s foot to determine arch and pressure points. By creating 3D computer-aided design (CAD) models from these scans, highly accurate sizes and shapes are built with very tight tolerances. This helps ensure optimal fit for the patient to support weak joints and limbs.

Moreover, according to Styles, 3D printing is being used to create patient-specific supports and braces, designed to enhance outcomes owing to their ability to create intricate lattice structures that can be used to create lightweight yet strong parts. “This ultimately makes orthoses more comfortable for patients,” he said. “If there is a requirement for a strong and durable brace, metal 3D printing often provides a stronger support than conventional methods.”

Clinical implications of 3D printing of orthotic devices include new possibilities of customization that have not been available with traditional methods.

The evolution

Computer-aided design of foot orthoses emerged in 1989. This method allowed creation of a digitized model of a foot, which would be sent to a laboratory to be milled from a block of plastic. Use of CAD models for orthoses was slow to evolve because equipment cost was high. With the emergence of 3D-printing machines, however, it has become easier to meet growing customer demand for highly customized parts.

Jay Raju, president of Cura BioMed, Inc., Morristown, New Jersey, noted that early 3D manufacturers offered products that did not necessarily provide the same value given by current solutions. The negatives, he added, far outweighed marginal benefits, and there was a wave of launches that never took off. One of the primary challenges, Raju said, has been the use of an entry-level printing technology called fused-deposit molding, which is “good for making prototypes but not great for industrial-level production.” Next-generation 3D printing companies have adopted a new manufacturing process that uses the more advanced selective laser sintering (SLS), which is used in other cutting-edge markets, such as the aerospace industry.

Because SLS technology incurs high fixed and operating costs, Raju added, it is not generally used for manufacturing orthoses. “But by marrying SLS technology with a robust supply chain from scan to design to manufacture to finishing, companies are now creating commercially viable products.”

With this convergence of supply chain and 3D technology, there should be a change in the functional orthotics market. Star Rapid’s Styles shared that, today, 3D CAD models are quite accurate and the cost of plastic 3D printing is relatively low, making this method better than standard methods, such as milling from a plastic block.


Commentary: We’re in a time of mass production of customized orthoses

3D printing is an accessible manufacturing option. Any other approach is just wrong.

By Chris Lawrie, MSc

As an engineer, I printed my first automotive part in 1989 and my first pair of insoles in 2010. It took until 2017 for the stars to align, however: 3D printing technology capable of printing a pair of shells quickly, in materials that meet the demands of the foot, at a production price point that means 3D printing is no longer just a premium offering.

It’s a fact: Today, labs can have shells made for a price that is comparable to shells manufactured by direct-milling polypropylene or positives. Scanners are off-the-shelf items that can, with the right app, give us results that make casting an insanely poor choice. Design software (such as FITFOOT360) can give you complete clinical control over a custom, print-ready device, and you can, case by case, choose whether to mill or print a shell or a positive. I describe this digital mass-customization process as simply “capture–design–make.”

What’s the key to us introducing 3D printing into our foot-health community (for good, this time)? It’s producing a device that is better clinically while being believable to both clinicians and patients; after all, 3D printing it is just another way of making something. Any strategy that presents 3D printing as a premium product or high technology is dated and flawed; it simply maintains the low-volume, high-price strategy that has slowed the evolution of 3D printing, in all markets, over the past 30 years. The recent move by Hewlett-Packard to promote the democratization of printed materials has enabled entrepreneurial companies (such as iOrthotics and FIT360) to capitalize on a wholesale approach to designing and manufacturing 3D-printed insoles. As a result, 3D-printed insoles are already the preferred choice of many labs worldwide.

This is an exciting time in the world of 3D printing—a time that we will all benefit from, as our colleagues in the dental world did nearly a decade ago. As you invest in new technology for rapidly capturing the human form to precisely represent a prescription, please, consider a digital process: from capturing the human form instantly, to creating a custom 3D prescription in seconds, to choosing the ideal “make” option for you, whether form, mill, or print.

To sum up, for the first time in this industry, 3D printing is an accessible manufacturing option. Be careful, however: Do not assume that you need to offer space-age printed devices to your customers… Some entrepreneurs have been here before, and have failed.

Chris Lawrie, MSc (Engineering Business Management), is chief executive officer of FIT360 Ltd (www.ff360-sw.com), developers of software, including FITFOOT360, for use by manufacturers of digital custom insoles.

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Clinical implications

3D printed foot orthoses are designed and manufactured using the latest digital technologies and require limited manual intervention. Industry experts say that this not only guarantees clinical accuracy of the product, required by clinicians for their patients, but also ensures that orthoses are of consistent quality, durability, and flexibility.

From a clinical perspective, Raju stated, the orthoses produced by 3D printing will deliver all the clinical modifications needed, while also making the insoles more flexible, durable, and ultra-light compared with co-poly– or carbon-based competing products. This may broaden the range of choices in shoe type and lifestyle available to patients.

Raju offered an example of how a 3D-printed orthosis can aid in correcting a pronated foot, in which the hind foot is directed into excessive valgus and impairs efficient heel strike and toe off in the gait cycle, causing calf pain and fatigue. The 3D-printed insoles have built-in hind-foot corrections specific to the patient’s deformity to permit a stable, neutral hind foot during the gait cycle.

Andrei Vakulenko, chief business development officer at Artec 3D, Luxembourg, believes the clinical implications of using 3D scanning and 3D printing are limitless. Following the creation of personalized 3D medical solutions, such as prosthetics, back braces, and even something as intricate as an ear, orthopedists are finding an industry that is constantly creating and improving the software and expanding the tools available for the seamless creation of both ready-made and custom orthoses.

For instance, Vakulenko said, the Robotics and Multibody Mechanics research group at Vrije Universiteit Brussel (University of Brussels) has, as one of its projects, a lower body–powered exoskeleton, built using the Artec Eva 3D scanner. The design uses a tightly fitting orthotic device for the user’s leg that is created by 3D-scanning of the limb. This process replaces the use of uncomfortable, messy plaster molds to capture the shape of a limb; the molds are then shipped to a manufacturer.

“The precise 3D scan is used to digitally model an orthosis that can be 3D printed,” Vakulenko said. “Once printed, the orthotic is reinforced with carbon fibers and epoxy composite. Creating this form-fitting interface between the user and device ensures less energy is lost by the exoskeleton’s actuators and mechanical components that are built around it.”

Bruce E. Williams, DPM, DABFAS, director of gait analysis studies at the Weil Foot & Ankle Institute, Chicago, Illinois, said the potential for 3D-printed devices is huge because of the ability to control segmental stiffness in a way that has never been done before. “There are huge benefits to being able to control specific segmental elements in an orthotic. This cannot be achieved with traditional polypropylene devices,” he said. “The ability to stiffen the medial arch, create more flexibility in the medial or lateral columns has huge benefits for athletes and even day-to-day patients.”

This variation in both local and directional flexibility reflects the biomechanical data from digital, dynamic analysis. “It results in lightweight devices that last longer than traditional orthotics, giving the patient better value for money,” Williams said.

For example, Dr. Williams has made orthoses with decreased stiffness of the lateral column specifically for athletes who have had, or are at high risk of having, a 5th metatarsal fracture. After implementing this modification, the pressures and length of high pressures under the 5th metatarsal decreased markedly and greatly reduced or minimized further risk to these athletes for that type of injury.

Norquist added that from a technical perspective, using 3D printing offers new possibilities of customization that have been impossible with traditional methods. What the clinician has ordered is what is received, fostering a trusting relationship with patients.

Getting results

Photo courtesy of RS Print

The process of using 3D printing can produce high-quality results, and Vakulenko shared that, with constant technological advances and new developments in the tools and materials being used, customized solutions are becoming lighter, more ergonomic, and more cost-effective. In most cases, customized 3D-printed orthoses have the potential to improve on standard methods in terms of accuracy, cost, and procedure. Using 3D scanning to create a model that is then 3D printed delivers the exact data required for sizing the orthosis, creating a perfect fit and a durable solution. Because the process is additive, there is no wasted material when creating parts, eliminating the risk of additional costs.

Williams added that some materials, such as nylon, are largely unbreakable and allow for significant variability in stiffness and flexibility. Norquist agrees: “The choice of the material wasn’t just a lucky guess,” he said. “PA 12 [nylon powder] is a material that lasts far better than, for example, EVA [ethylene vinyl acetate] or cork and leather.”

However, Vakulenko cautioned that, just as with anything else, there is always room for improvement. “3D printing is the best option for personalized orthoses; however, if an orthotic is mass-produced, it will be more cost-effective to do so with a more traditional manufacturing process,” he said. “In addition, 3D printing can be rather slow compared to, for example, milling machines.”

Looking ahead

3D printing is already being used in orthopedics to create implants and in minimally invasive surgery to create small devices, resulting in less tissue damage during operations. With the growth of this technology, most believe that use will be more widespread in the future.

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Although 3D printing for the medical industry is highly practical for the creation of customized devices, Styles noted that, regrettably, using this process for mass production of supports and braces may not become a reality in the near future. Until plastic 3D-printing machines reach commercial speed, he explained, the time needed to create a part will be days, and the size of a finished orthotic is limited to the size of the 3D machine’s print bed—typically smaller than what can be made using computer numerical control machining or custom casting.

Ultimately, Raju explained, the biggest caveat for the 3D-printed orthotics industry is not what technology is being used but, rather, how that technology is married with the entire value chain of production—from design to global supply chain to product pricing to quality control to research and to design and innovation.

One key competitive advantage of 3D printing is that it can be used to manufacture objects with complex geometry, such as an object within another object that cannot be created by any means other than 3D printing. In the long run, 3D printing may eventually replace traditional methods of manufacturing, both mass-produced and customized, in numerous industries.

Vakulenko said that most traditional methods of creating prosthetics are approaching obsolescence, and practicing orthopedists are embracing the new 3D technologies for a much cleaner, faster, and more precise process. “Today, using both high-tech 3D-printing and 3D-scanning technologies opens up a large variety of possibilities and allows for a much more flexible workflow with the use of the cutting-edge systems,” he said. “With the development of highly advanced tools to tailor to the healthcare industry, it is safe to say that we are now witnessing a significant shift in the procedures of the orthotics field.”

Keith Loria is a freelance medical writer.

via The future is now— Implications of 3D technology for orthoses | Lower Extremity Review Magazine

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[WEB SITE] Project3 – Flexo-glove

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Project Description

Flexo-glove is a 3D printed soft exoskeleton robotic glove with compact and streamlined design for assistance in activities of daily livings and rehabilitation purposes of patients with hand function impairment.

Specifications:

  • Overall weight of 330g including battery
  • Providing 22N pinch force, 48N power grasp force and object grasp size of up to 81mm in diameter
  • Two control modes: intention-sensing via wireless surface EMG for assistive mode and externally-directed via an accompanying smartphone

Project Details: —> Visit site

My Role:

  • Initiated the project with the idea of using soft 3D printed materials in design of the Flexo-glove inspired by X-Limb
  • Performed feasibility study for using cable-driven mechanism in actuation of rehabilitation glove
  • Leading a group of four mechatronics engineering students to fabricate the prototype and characterise the grip forces

Awards

  • Received Dyason fellowship, $5000 travel fellowship awarded by Melbourne Robotic Lab. to visit Harvard BioRobotics Lab

Related Publications

 A. Mohammadi, J. Lavranos, R. D. Howe, P. Choong and D. Oetomo

  Flexo-glove: A 3D Printed Soft Exoskeleton Robotic Glove for Impaired Hand Rehabilitation and Assistance

  40th International Engineering in Medicine and Biology Conference (EMBC), 2018.

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[ARTICLE] A Finger Exoskeleton Robot for Finger Movement Rehabilitation – Full Text HTML

Abstract

In this study, a finger exoskeleton robot has been designed and presented. The prototype device was designed to be worn on the dorsal side of the hand to assist in the movement and rehabilitation of the fingers. The finger exoskeleton is 3D-printed to be low-cost and has a transmission mechanism consisting of rigid serial links which is actuated by a stepper motor. The actuation of the robotic finger is by a sliding motion and mimics the movement of the human finger. To make it possible for the patient to use the rehabilitation device anywhere and anytime, an Arduino™ control board and a speech recognition board were used to allow voice control. As the robotic finger follows the patients voice commands the actual motion is analyzed by Tracker image analysis software. The finger exoskeleton is designed to flex and extend the fingers, and has a rotation range of motion (ROM) of 44.2°.

1. Introduction

Statistically, one in six people in the world will have a stroke [1] at some time, or develop some debilitating bone condition. Most strokes are caused by an interruption of the blood supply to part of the brain. It is very important for stroke patients to move the parts of the body that have been affected to restore and retrain movement. This rehabilitation is very important for the patient and is particularly so for the achievement of full movement. This not only helps to maintain muscle tension and strength, and increase durability, but also promotes blood circulation [2].
Rehabilitation systems have been extensively studied for effective restoration and training of muscle activity in the arm or hand [3,4]. The degree of upper limb rehabilitation is also used in clinical tests [5]. However, a finger exoskeleton is more difficult to design than one for the arm because it requires many more degrees of freedom (DOF) of motion and this involves small moving parts [6]. The design of a typical finger mechanism is complicated, has involved control requirements, and is usually very expensive. To reduce the cost and simplify the fabrication and operation, many people working on the problem began to use underactuated mechanisms in the design of a robot finger [7,8].
An underactuated mechanism has fewer driving sources than the number of DOF. Such an underactuated finger mechanism can be simple in structure, and is easily made even simpler by linking the motion of individual joints, or linking the motion of one finger to another finger [9]. Tendon-actuated and linkage mechanisms are the most common underactuated mechanisms in current use. However, the development and progress of robotic engineering has allowed the underactuated robot to include more DOF and has also lowered the complexity in many different applications.
A tendon-driven mechanism [10] can simply use a nylon line to stretch and bend the fingers. It has the advantage of simplicity and also absorbs shock; however, the line itself is under tension, which puts more load on the finger joints that increases friction forces, and is itself subject to elastic deformation. This kind of mechanism can only be used under a small load. Linkage-type mechanisms driven by auxiliary links to control the fingers have advantages. They are easy to analyze and mechanically rigid, but the many links lead to a loose structure and a humanoid robot finger comparable in size to that of a real finger is not easy to achieve [11].
Various hand exoskeleton technologies for rehabilitation and assistive robotics have recently been developed [12]. To design a proper hand or finger exoskeleton, the biomechanics of the hand/finger, robotic mechanisms, and control methods must be considered. Hand exoskeletons can be driven by different actuators, including electric actuators, pneumatic actuators, and smart material actuators [12]. Allota [13] used external servo motors to drive the exoskeleton fingers, whereas the radio control (RC) servomotors pulled the cables to actuate the fingers in the opening or closure phase. Polygerinos [14] used a soft pneumatic glove to produce bending motions to follow the motion of human fingers.
In this paper, a rehabilitative robotic finger is presented that can be used to maintain muscle strength through repetitive action, which also has the effect of functional recovery by rebuilding the sensorimotor links through the reorganization process in the damaged brain. To avoid the limitations of the heavy and bulky exoskeleton, the design of the finger used an underactuated mechanism, and a 3D printer was used to fabricate a prototype. Thus, the exoskeleton is affordable and competes with conventional therapy costs. In continuous passive motion therapy, a patient usually cannot control the movement through conscious effort; therefore, we used auto speech recognition to help patients control rehabilitation efforts themselves. A specific key word was used to start the robot and a carefully chosen stepper motor was used to power the mechanism. The actual motion was analyzed using the Open Source Physics tool, Tracker.

2. Design and Simulation

The design of the exoskeleton robot was undertaken with a number of important considerations in mind, the most pertinent of which were shape, size, cost, and weight. The weight and cost of the exoskeleton are critical to the users. In our design, the cost (around 30 US dollars) is affordable and competes with conventional therapy costs, while the weight is less than 45 grams. The device needed to fit on a finger and its movement had to follow the finger of the disabled patient. Before embarking on the project, we first studied finger bending motion as well as the general structure of finger muscles and bones. The input torque is set to 30 N-mm according to the motor selected. In the experiment, this torque can move the finger slowly, which is suitable for slight stroke patients. For moderate stroke patients, a higher torque motor with a similar size can be selected with a slight increase of cost and weight. We used Solidworks™ and Autodesk Inventor™ to both design and analyze the system.

2.1. Design

The slider-type robotic finger we designed can be divided into two main parts: the slider itself and the N-shaped linkage, as shown in Figure 1. The design concept of the slider mechanism was to locate the centers of the two arc-shaped sliders on the proximal and distal finger joints separately and to ensure the robotic finger followed human finger motion. In addition, the N-shaped linkage mechanism was designed to connect the proximal and distal arc-shaped sliders and to make them bend together. The N-shaped linkage used is simple and reduced the size of the finger.
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Figure 1. Design of the finger exoskeleton robot that allows the finger to curl from (a) extended to (d) flexed.

The prototype robotic finger has three sliders, five links, ten bolts, and one motor. As the motor rotates, the blue crank moves the gray coupler forwards or backwards. The gray coupler pushes and pulls the yellow slider arm, making it move along the slot. When the yellow slider moves, this causes the green link, or N-shaped linkage, to rotate, which in turn causes the yellow and outer red sliders to move together. The N-shaped linkage continues to push and pull the outer red slider, causing it to move along the slot. The outer red slider connects to the human finger and causes it to bend.[…]

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[Abstract] Gamification of Hand Rehabilitation Process Using Virtual Reality Tools: Using Leap Motion for Hand Rehabilitation

Abstract:

Nowadays virtual reality (VR) technology give us the considerable opportunities to develop new methods to supplement traditional physiotherapy with sustain beneficial quantity and quality of rehabilitation. VR tools, like Leap motion have received great attention in the recent few years because of their immeasurable applications, whish include gaming, robotics, education, medicine etc. In this paper we present a game for hand rehabilitation using the Leap Motion controller. The main idea of gamification of hand rehabilitation is to help develop the muscle tonus and increase precision in gestures using the opportunities that VR offer by making the rehabilitation process more effective and motivating for patients.

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Source: Gamification of Hand Rehabilitation Process Using Virtual Reality Tools: Using Leap Motion for Hand Rehabilitation – IEEE Xplore Document

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[WEB SITE] The future of footwear and orthoses is here. Now what?

A shift in tone was apparent at this year’s Ortho Technology Forum (OTF), and not just because the focus of the event has been expanded to include design and manufacturing technologies for footwear as well as foot orthoses. Speakers and attendees are no longer just speculating about how technology will change the footwear and foot orthosis industries—because those changes are already occurring in mainstream, high-profile ways.

The key difference between 3D laser scanning (left) and photogrammetry (right) is accuracy, experts say.

The questions now focus on how foot care specialists’ role will change in an industry in which start-up companies often champion technical bells and whistles at the expense of accuracy and clinical relevance, and how clinicians themselves can use technology to their advantage to stay competitive.

“The war has started,” said Chris Lawrie, Healthcare Business Development Manager for Birmingham, UK-based Delcam Healthcare Solutions, which organized the April event held in Vancouver, Canada.

Lawrie was speaking specifically about how the growing accessibility of 3D printing technology has created a market for entrepreneurial footwear and orthoses manufacturers who are less con­- cerned with clinical effectiveness than their bottom line. But the assessment could as easily be applied to other aspects of technology being used by entrepreneurs to battle clinicians for a share of those markets.

“There isn’t a part of our industry that isn’t being affected by technology right now,” said Graham Archer, CPed(C), vice president of pedorthic services at Kintec Footlabs and president of Kiwi Software Solutions, both in Vancouver, in an OTF presentation.

The challenge for clinicians, and for other players in the footwear and orthotics markets for whom quality is a priority, will be to prove that new technologies aren’t just for newcomers. OTF presenters detailed multiple ways in which new tools and processes can help even established labs and clinics become more efficient, more accurate, and more profitable.

“The key is how to get around the paradigm shift to take advantage of things like new materials and new design opportunities,” Lawrie said.

3D printing

Feetz prototype custom shoes

It’s tempting to dismiss 3D printing, also known as additive manufacturing, as the province of start-up companies looking to make a quick buck off drugstore-grade insoles or creative types designing futuristic-looking shoes that nobody in the real world would ever wear. But 3D printing is also being employed by a number of companies in ways that could potentially have much more practical and even clinical applications.

Chattanooga, TN-based Feetz is currently in the beta-testing phase of its personalized shoe business, which aims to 3D-print individual pairs of shoes based on either an in-store scan or on customers’ digital photos of their feet taken with the company’s app.

“One in three consumers are seeking personalization in their shoe purchases, and one in five Americans have foot issues that affect their shoe purchases,” Feetz CTO Nigel P. Beard said in an OTF presentation, while modeling a bright green prototype pair of Feetz shoes. “Our motto is: ‘You’ll never try on another pair of shoes again.’”

With few footwear-specific materials available that are compatible with 3D printing, the company ended up developing its own materials, ranging from ceramics to antimicrobials to scented polymers, Beard said.

Continue —> The future of footwear and orthoses is here. Now what? | Lower Extremity Review Magazine.

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