8. Open source hardware: Robotic Arm#

Research#

Prosthetics of the 3rd Industrial Revolution#

The democratization of digital fabrication machinery has opened the opportunity for manufacturing customized solutions in less time and for much cheaper than traditional manufacturing. It has been particularly transformative in the medical field with new advancements in technology already showing signs for a new era of prosthetics design. The disruptive nature of these digitally fabricated prostheses can also prove revolutionary in transforming the distribution of devices and care in fragile populations, particularly in alleviating the current situation in third world countries through a number of different approaches in the manufacturing process.

Advantages of 3D Printed Prosthetics

  1. Customization and Personalization

The greatest advantage that 3D printed prostheses provide is the freedom to produce custom-made products that can provide great value for every individual patient. Each device has the ability to be personalized according to individual needs and requirements. Design customizations are adaptable to suit the variety of residual limbs along with accommodating specialty designs tailored for specific activity use such as driving and holding a pen.

  1. Increased Cost Efficiency

Another important benefit offered by 3D printed prosthetics is the ability to produce items cheaply. The average cost of a traditional upper limb prosthetic costs $2,400 in Jordan, which is unaffordable to the 60 percent of refugees across Jordan now living below the national poverty line. This cost is also unfathomable for one in six Syrian refugee households living in abject poverty on less than $40 per month [UNHCR 2015]. The average cost of a 3D printed prosthetic is only a fraction of the cost at $50. This cost efficiency is especially important in designing for children whose limbs are quickly outgrown and costly to replace. With the current cost of traditionally manufactured prosthetics, many families forgo prostheses altogether as they have no other option.

  1. Enhanced Productivity

The time required for the production and shipping of a traditionally manufactured prosthetic is up to 6 weeks. In contrast, 3D printing only requires some hours, ranging from 12- 30 hours to print and assemble depending on size, quality and design. In addition to speed, the resolution, accuracy and strength of 3D printed prosthetics are also markedly improved and are actually preferred to more expensive myoelectric prosthetics [Simon, 2014]. 3D printed prosthetics also weight about 160 grams for an adult-sized hand, greatly improving the weight compared to the traditionally heavy arm prosthetics which cause inflammations and are often discarded over time.

  1. Collaboration and Democratization

Another beneficial feature offered by 3D printed prosthetics is the democratization of the design and manufacturing of goods. The nature of 3D printing as data files offers an unprecedented opportunity to share amongst researchers and collaborate, providing the ability to rapidly innovate with global communities in concert with specialists on the ground. Additionally, Fab Labs or other makerspaces with internet access have the capability to print and assemble these devices by accessing the fabrication files online for those with no internet access. The open-source model has set off a wave of community-driven prosthetic designs. Online communities, like E-Nable, have provided platforms for volunteers to be involved in the design process through sharing of open- source files. Currently, there are numerous examples of open-source prosthetic designs but for the purposes of this research, the focus will be on the three most relevant designs: the Cyborg Beast, the Flexy-Hand, and the Custom Partial Finger Replacement. These 3D printed designs all offer limited and simple functionality. They are actuated through body-powered tension cables and have one range of motion: opening or closing.

The Cyborg Beast and Flexy-Hand 2 both offer a thumbless version depending on the user’s resultant limb, and the Partial Finger Replacement is designed to fit over individual finger sockets.

Using Simplify3D to Print a Prosthetic Hand on a Single 6 x 9” Build Plate (3D Universe)#

To make a 3D printed hand for someone who needs one, please visit: http://www.facebook.com/enableorganization http://enablingthefuture.org

To buy Simplify3D, please visit: http://shop3duniverse.com/products/simplify3d-software

To buy a FlashForge Creator X, please visit: http://shop3duniverse.com/collections/3d-printers/products/flashforge-creator-x

To buy a kit with the assembly materials you need to make your own Cyborg Beast 3D printed hand, please visit: http://shop3duniverse.com/collections/3d-printable-kits/products/e-nable-hand-assembly-materials-kit-cyborg-beast-edition

Assembling and Testing the Cyborg Beast 3D Printed Prosthesis (3D Universe)#

Next Generation of 3D Printed Prosthetic Hands – The Flexy-Hand 2 – Looks and Feels More Realistic#

The “Flexy-Hand“, a realistic looking 3D printed hand that was printed using FilaFlex flexible filament. Steve Wood, the designer of the hand, and founder of mechanical design consultancy company, Gyrobot Ltd. told us that he had created the hand to be used one day as a prosthetic device. At the time, however, it was not a functioning prosthetic hand, just a hand that could be manipulated by pulling cables (artificial tendons) attached at the wrist.

As many of us know, there have been many 3D printed prosthetic devices created by both Robohand, and members of e-NABLE. Both are organizations that strive to create affordable 3D printed prosthetics for those in need. One thing you will notice when looking at the typical 3D printed prosthetic hand, is that they are very robotic looking. Designs such as the Cyborg Beast, and the Talon Hand work very well, but they look like they could be the hand of a 25th century cyborg beast (thus the name).

Steve Wood, a self proclaimed “tinkerer, maker, breaker and fixer”, wanted to create something different. He wanted to create a 3D printed prosthetic hand that could act and look as close to the real thing as possible. “Since the launch of the (original) Flexy-Hand, I was instantly getting requests to try and turn the original concept into something more functional, but I originally thought this would be better left to the more experienced prosthetic builders out there to do,” Wood tells 3DPrint.com. “However, to date nothing significant has emerged so I thought about doing something myself.”

The catalyst for getting Wood to reignite interest in advancing the Flexy-Hand to its next stage in development, came when Recreus, the manufacturers of Filaflex filament came to him and asked for his help in trying to come up with a prosthetic for a little girl named Vega.

Just two week ago, Wood decided to set out and start designing the second iteration of the Flexy-Hand — one which could be used as a prosthetic device. Doing it himself, was not the easiest task in the world, but Wood managed. He had to take the concept of the original Flexy-Hand and create a device that could actually be put onto a human being’s arm and function like a real hand. What he came up with is beyond amazing.

Just this morning, Wood contacted 3DPrint.com, with some good news:

“The hand has just been launched and is still “hot off the print-bed”, so I am waiting for adoption by the community, and feedback from this will be important for improvements. However, the mechanism works as intended, in the same way as Robohand and Cyborg Beast, you flex your wrist and the fingers close. I have used nylon fishing line, which gives a little bit of stretch for an adaptive grip, however, traditional tendon cord would be better for increased grip strength. The CAD body of the hand can also be twisted/manipulated in Meshmixer so a more individualized grip position or socket shape can be achieved relatively easily.”

Working from photos of the little Spanish girl, Vega, Wood re-modeled the Flexy-Hand, using Meshmixer and Blender to sculpt out the palm and provide a gauntlet attachment for the hand. Recreus has just began scaling down the hand and printing the parts out in Spain for little Vega. It should be interesting to see how she likes it.

The majority of the Flexy-Hand 2 is 3D printed. It does consist of a few additional pieces which have not been produced on a 3D printer. They include the tendon cord, (5) M2 screws (used as tensioners), Velcro style straps, and foam padding (if needed). It only requires about 1/3 kg of filament to create, and an entire prosthetic hand can be created for less than £15 (approximately $25.75). Not bad for a prosthetic hand, when traditional prosthetics cost in the $50,000+ range.

Some of interesting and exciting features of the Flexy-Hand 2 are:

Wood would also like to thank Recreus, the maker of Filaflex filament, who donated a Witbox 3D printer to his cause, and all the people who provided ideas and suggestions to him along the way.

It should be interesting to see how e-NABLE plans to utilize the Flexy-Hand 2 in the development of future prosthetic devices that they make for children. While the Cyborg Beast, and similar hands function very well, there will surely be children who prefer a more realistic looking/feeling hand. You have to love how far 3D printing has come in just a few years. Only 2 years ago, it was almost unheard of to hear about having 3D printed prosthetic devices. Now we are at a point, where the technology and methods used are advancing at a very rapid rate. Where will we be in another 2 years from now?

Hero Arm by Open Bionics#

Meet the World’s First Bionic Drummer | Freethink Superhuman#

Robotic Arm Inspired By Elephants#

Robot arms are expensive to build and dangerous to operate. If a robot system malfunctions, people can be injured. This is not the case of ISELLA, a bionic robot arm that is kind on the purse and gentle with people. An elephant’s trunk served as inspiration for its design.

Elbow joint of an ISELLA robot arm. It will later be enclosed in a padded sleeve to provide a cushioned, safer outer surface.

Robot arms are expensive to build and dangerous to operate. If a robot system malfunctions, people can be injured. This is not the case of ISELLA, a bionic robot arm that is kind on the purse and gentle with people. An elephant’s trunk served as inspiration for its design.

It is long, gray, soft and – endowed with no fewer than 40,000 muscles – extremely agile. An elephant uses its trunk to grasp objects and for drinking. With their trunks, the pachyderms can tear down trees and pull heavy loads, and yet are also capable of performing extremely delicate manipulations. Researchers at the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart have used the elephant’s trunk as a design model. “Its suppleness and agility gave us the idea for a bionic robot arm, ISELLA,” recounts Harald Staab, the IPA researcher who invented and developed the technology.

Robot arms often present a risk to human operators – a technical hitch can provoke wild, uncontrolled movements. Not so ISELLA. Whereas conventional robot arms have only one motor to drive each articulated joint, ISELLA has two, grouped in pairs so that if one motor control should fail, the second takes over to prevent uncontrolled movements. “Unlike pneumatic or hydraulic actuation systems, our robot arm has a simple, low-cost muscle, consisting of a small electric motor with a drive shaft and a cord,” explains Staab.

In the same way as a tendon attaches one muscle to another, the cord links two related moving parts. The drive shaft is attached to the midpoint of the cord. When the shaft turns, the cord wraps around it in both directions, forming a kind of double helix. The researchers have dubbed this DOHELIX. “The shaft is no thicker than the cord, but is strong enough to resist breaking.

Consequently, it has a higher transmission ratio than a conventional geared motor,” Staab explains. This has been achieved using elastic materials with a very high tear strength – the type of material used to manufacture yacht sails and hang gliders. As a result, DOHELIX is much cheaper and more energy-efficient than a system of gears. Its tensile force is many orders of magnitude greater than its own weight, and drive systems based on the DOHELIX concept can be used in applications on all scales – from micrometer-scale muscles to cranes in container seaports.

The ISELLA robot arm consists of a total of ten DOHELIX muscles, providing a flexor and an extensor for each articulated joint, four situated in the elbow and six in the upper arm. The robot arm is as flexible as a human arm. “At present we are working on the elbow,” relates Staab. Possible applications for ISELLA include medical rehabilitation, for instance in therapy to restore the use of injured limbs, and low-cost, flexible prosthetic devices. Such devices could be commercially available within about two years, Staab estimates.

Making a 3D Printed Humanoid Robot | Developed by Ryan Gross#

The Mind-Controlled Bionic Arm With a Sense of Touch#

Code Example#

Use the three backticks to separate code.

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(LED_BUILTIN, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);                       // wait for a second
  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);                       // wait for a second
}

Video#

From Vimeo#

Sound Waves from George Gally (Radarboy) on Vimeo.

From Youtube#

3D Models#

Dita's Gown by Francis Bitonti Studio on Sketchfab