Shooting For The First Time With Help From A Raspberry Pi

July 5, 2018 by Dan Maloney 15 Comments

Like many people, [Mike] has a list of things he wants to do in life. One of them is “fire a gun with a switch,” and with a little help from some hacker friends, he knocked this item off last weekend.

For those wondering why the specificity of the item, the backstory will help explain. [Mike] has spinal muscular atrophy, a disease that was supposed to end his life shortly after it began. Thirty-seven years later, [Mike] is still ticking items off his list, but since he only has voluntary control of his right eyebrow, he faces challenges getting some of them done. Enter [Bill] and the crew at ATMakers. The “AT” stands for “assistive technologies,” and [Bill] took on the task of building a rig to safely fire a Glock 17 upon [Mike]’s command.

Before even beginning the project, [Bill] did his due diligence, going so far as to consult the Bureau of Alcohol, Tobacco, and Firearms (ATF) and arranging for private time at a local indoor gun range. The business end of the rig is a commercially available bench rest designed to control recoil from the pistol, which is fired by a servo connected to the trigger. The interface with [Mike]’s system is via a Raspberry Pi and a Crikit linked together by a custom PCB. A PiCam allowed [Mike] to look down the sights and fire the gun with his eyebrow. The videos below show the development process and the day at the range; to say that [Mike] was pleased is an understatement.

We’re not sure what else is on [Mike]’s list, but we see a lot of assistive tech projects around here — we even had a whole category of the 2017 Hackaday Prize devoted to them. Maybe there’s something else the Hackaday community can help him check off.

Continue reading “Shooting For The First Time With Help From A Raspberry Pi” →

An Open Source Sip-and-Puff Mouse For Affordable Accessibility

April 27, 2018 by Dan Maloney 22 Comments

At the core of any assistive technology is finding a way to do something with whatever abilities the user has available. This can be especially difficult in the case of quadriplegia sufferers, the loss of control of upper and lower limbs caused by spinal cord damage in the cervical region. Quadriplegics can gain some control of their world with a “Sip-and-puff” device, which give the user control via blowing or sucking on a mouthpiece.

A sip-and-puff can make a world of difference to a quadriplegic, but they’re not exactly cheap. So to help out a friend, [Jfieldcap] designed and built an open source sip-and-puff mouse on the cheap. As is best for such devices, the design is simple and robust. The hollow 3D-printed mouthpiece acts as handle for a joystick module , and a length of tubing connects the mouthpiece to a pressure sensor. An Arduino lets the user move his head to position the cursor; hard sips and puffs are interpreted as left and right clicks, while soft mouth pressure is used for scrolling. In conjunction with some of the accessibility tools in modern OSes and personal assistant software like Siri or Cortana, the sip-and-puff opens up the online world, and for all of $50 in material.

We’re impressed by the effort and the results, but we worry that the standard PLA used for the mouthpiece won’t stand up to the cleaning it’ll need. Of course, printing extra mouthpieces is easy, but since it’s going to be in contact with the mouth, perhaps a review of food-safe 3D-printing is in order.

DIY Text-to-Speech With Raspberry Pi

March 2, 2018 by Kristina Panos 10 Comments

We can almost count on our eyesight to fail with age, maybe even past the point of correction. It’s a pretty big flaw if you ask us. So, how can a person with aging eyes hope to continue reading the printed word?

There are plenty of commercial document readers available that convert text to speech, but they’re expensive. Most require a smart phone and/or an internet connection. That might not be as big of an issue for future generations of failing eyes, but we’re not there yet. In the meantime, we have small, cheap computers and plenty of open source software to turn them into document readers.

[rgrokett] built a RaspPi text reader to help an aging parent maintain their independence. In the process, he made a good soup-to-nuts guide to building one. It couldn’t be easier to use—just place the document under the camera and push the button. A Python script makes the Pi take a picture of the text. Then it uses Tesseract OCR to convert the image to plain text, and runs the text through a speech synthesis engine which reads it aloud. The reader is on as long as it’s plugged in, so it’s ready to work at the push of a button. We can probably all appreciate such a low-hassle design. Be sure to check out the demo after the break.

If you wanted to use this to read books, you’d still have to turn the pages yourself. Here’s a BrickPi reader that solves that one.

Continue reading “DIY Text-to-Speech With Raspberry Pi” →

Rapidly Prototyping Prosthetics, Braille, And Wheelchairs

February 23, 2018 by Anool Mahidharia 4 Comments

We live in an amazing time where the availability of rapid prototyping tools and expertise to use them has expanded faster than at any other time in human history. We now have an amazing ability to quickly bring together creative solutions — perfect examples of this are the designs for specialized arm prosthetics, Braille printing, and custom wheelchair builds that came together last week.

Earlier this month we published details about the S.T.E.A.M. Fabrikarium program taking place at Maker’s Asylum in Mumbai. The five-day event was designed to match up groups of makers with mentors to build assistive devices which help improve the condition of differently-abled people.

The participants were split into eight teams and they came up with some amazing results at the end of the five-day program.

Hands-On: Prosthetic Designs That Go Beyond

Three teams worked on projects based on Bionico – a myoelectric prosthesis

DIY Prosthetic Socket – a Human Machine Interface : [Mahendra Pitav aka Mahen] lost his left arm during the series of train bomb blasts in Mumbai in 2006, which killed 200 and injured over 700 commuters. He uses a prosthetic arm which is essentially a three-pronged claw that is cable activated using his other good arm. While it is useful, the limited functionality restricted him from doing many simple things. The DIY Prosthetic socket team worked with [Mahen] and [Nico Huchet] from MyHumanKit (who lost his right arm in an accident 16 years back), and fabricated a prosthetic forearm for [Mahen] with a modular, 3D printed accessory socket. Embedded within the arm is a rechargeable power source that provides 5V USB output at the socket end to power the devices that are plugged in. It also provides a second port to help recharge mobile phones. Also embedded in the arm was an IR reflective sensor that can be used to sense muscle movements and help trigger specific functions of add-on circuits, for example servos.

Continue reading “Rapidly Prototyping Prosthetics, Braille, And Wheelchairs” →

IoT Doorman: Eye-Controlled Door For A Girl With Cerebral Palsy

January 27, 2018 by James Hobson 11 Comments

Kyleigh has an eye-controlled computer on her wheelchair but something as simple as her bedroom door was still beyond her reach… until now! [Bill Binko], recently filmed a demo of an automatic, IoT door opener built for the young girl with cerebral palsy. [Bill] is a co-founder of ATMakers, an organization that enables makers interested in assistive technologies to collaborate with users to improve quality of life.

Using her eye tracking tablet (PRC Device), Kyleigh has two new icons that make the relevant call to a website, pushing a simple command to either open or close her bedroom door. The device attached to the door uses an Adafruit M0 WiFi Feather board, a DC stepper motor and wheel, a UBEC buck converter, and a potentiometer.

Since other family members are also going to be opening and closing the door, there’s potentiometer which measures the door position for proper operation next time Kyleigh wishes to use the door. The installation also maintains a fairly inconspicuous profile for the assistance it gives — the ‘brain’ is enclosed in a small box on the door, with the motor only slightly larger on the door’s base.

[Bill] believes the project has a few quibbles and wants to work out a smaller wait before the open/close process is executed and optimizing the open/close speed. You have to check out the video below to see that it works really really. We’re also excited to see Kyleigh using her gaze control to talk to an Amazon Echo. [Bill] foresee a door control improvement that links it to Alexa. And how much did it cost to improve the quality of life for this young girl? $70.

We love seeing makers help people, and cannot wait to see what 2018 will bring! If you’re looking for more inspiration, don’t miss the eye-controlled wheelchair project called Eyedrivomatic which won the 2015 Hackaday Prize. There’s also the top Assistive Technology projects from the Hackaday Prize.

Continue reading “IoT Doorman: Eye-Controlled Door For A Girl With Cerebral Palsy” →

Hackaday Prize Entry: Clunke Button Powers Accessibility

October 5, 2017 by Kristina Panos 11 Comments

An AT button is a device that helps people with all kinds of physical disabilities to interact with their world. There isn’t much to them, just a switch wired up to a 3.5mm mono plug or jack, but the switch is installed in a large button housing that’s easy to operate.

These buttons can be used with any appliance or toy that can be adapted for mono input. They’re a simple piece of technology that makes a world of difference, but for some reason, they cost around $65 each. Because of this, people make their own simple switches, but these aren’t usually sturdy or long-lasting. [Christopher] thinks they should cost way less than that and set out to make buttons for about $10 in materials. Aside from the printed files, all you really need to make a Clunke button is one Cherry MX in your favorite shade of blue, blue, or blue, and either a 3.5mm mono jack or plug, depending on preference.

[Christopher] and his team devised the Clunke Button in collaboration with the local United Cerebral Palsy chapter as part of their senior design project. When it came time to present the project, they wanted to find a way to be able to pass a Clunke button around the audience and have it do something when pressed. They made an interactive ticker by adding an ESP-01 and a battery. [Christopher] has since taken over the project and continues to improve the design as he progresses through the Prize finals. Code for the ticker is available on GitHub, and the button STL files are on Thingiverse.

Hackaday Prize Entry: OrthoSense, A Smart Knee Brace For Physical Therapy

September 25, 2017 by Kristina Panos 4 Comments

If you have knee surgery, you can probably count on some physical therapy to go with it. But one thing you might not be able to count on is getting enough attention from your therapist. This was the case with [Vignesh]’s mother, who suffers from osteoarthritis (OA). Her physiotherapist kept a busy schedule and couldn’t see her very often, leaving her to wonder at her rehabilitation progress.

[Vignesh] already had a longstanding interest in bio-engineering and wearables. His mother’s experience led him down a rabbit hole of research about the particulars of OA rehabilitation. He found that less than 35% of patients adhere to the home regimen they were given. While there are a lot of factors at play, the lack of feedback and reinforcement are key components. [Vignesh] sought to develop a simple system for patients and therapists to share information.

The fruit of this labor is Orthosense, an intelligent knee brace system that measures gait angle, joint acoustics, and joint strain. The user puts on the brace, pairs it with a device, and goes through their therapy routine. Sensors embedded in the brace upload their data to the cloud over Bluetooth.

Joint strain is measured by a narrow strip of conductive fabric running down the length of the knee. As the user does their exercises, the fabric stretches and relaxes, changing resistances all the while. The changes are measured against a Wheatstone bridge voltage divider. The knee’s gait angle is measured with an IMU and is calculated relative to the hip angle—this gives a reference point for the data collected by the strain sensor. An electret mic and a sensitive contact mic built for body sounds picks up all the pops and squeaks emitted by the knee. Analysis of this data provides insight into the condition of the cartilage and bones that make up the joint. As you might imagine, unhealthy cartilage is noisier than healthy cartilage.

[Vignesh]’s prototype is based the tinyTILE because of the onboard IMU, ADC, and Bluetooth. Since all things Curie are being discontinued, the next version will either use something nRF52832 or a BC127 module and a la carte sensors. [Vignesh] envisions a lot for this system, and we are nodding our heads to all of it.