We are accustomed to medical devices being expensive, but sometimes the costs seem to far exceed reasonable expectations. At its most simplistic, a hearing aid should just be a battery, microphone, amplifier, and speaker, all wrapped in an enclosure, right? These kinds of parts can be had for a few dimes, so why do modern hearing aids cost thousands of dollars, and why can’t they seem to go down in price?
Getting a child’s attention can be difficult at the best of times. Add deafness into the picture, and it’s harder again. [Jake]’s daughter recently had to go without her cochlear implants, raising this issue. Naturally, he whipped up some hardware to solve the problem.
[Jake]’s solution was to devise a vibrating wristband that could be used to get his daughter’s attention. An Adafruit Trinket M0 is used to vibrate a pager motor, using a DRV2605 motor driver. This is paired with a Tile Bluetooth device, allowing the unit to interface with Google Assistant. This allows [Jake] to get his daughter’s attention with a simple voice command to a smartphone, tablet or smart speaker.
While [Jake]’s daughter will regain her cochlear implants soon, they do have limitations as far as hearing distant sounds and working in high-noise environments. It’s likely that this little gadget will prove useful well into the future, and could serve others well, too. Wearable notification devices are growing more popular; this OLED ring is a particularly good example. Video after the break.
If you don’t have hearing loss, it is easy to forget just how much you depend on your ears. Hearing aids are great if you can afford them, but they aren’t like glasses where they immediately improve your sense in almost every way. In addition to having to get used to a hearing aid you’ll often find increased noise and even feedback. If you’ve been to a theater lately, you may have noticed a closed caption display system somewhere nearby that you can sit within visual range of should you be hard of hearing. That limits your seat choices though, and requires you to split your attention between the stage and the device. The National Theatre of London is using Epson smart glasses to put the captions right in your individual line of vision (see video below).
The Epson glasses are similar to the Google Glass that caused such a stir a few years ago, and it seems like such a great application we are surprised it has taken this long to be created. We were also surprised to hear about the length of the project, amazingly it took four years. The Epson glasses can take HDMI or USB-C inputs, so it seems as though a Raspberry Pi, a battery, and the glasses could have made this a weekend project.
Hearing impairment, either partial or total, is a serious problem afflicting a large number of people. Almost 5% of the global population has some form of hearing disorder. For those affected by this disability from birth, it further impacts the development of language and speech abilities. In recent years, cochlear implants are increasingly being used to address this problem. These implants consist of two parts – the receiver and electrode array are implanted under the skin near the ear (with the electrode array terminating inside the Cochlea), while the microphone, electronics, transmitter and power source are attached on the outside. Often, the external unit has to be removed – for example, when the person needs to sleep. This is particularly so in the case of young children. The external unit is fairly large compared to their head and causes discomfort during sleep. And parents are worried that the expensive device could get damaged when the child is sleeping. This leads to the alarming situation where the child is asleep and has no audio sensory inputs being received from the surroundings. Not only can they not hear morning alarms, but also cannot react when there is an emergency situation such as a smoke alarm going off.
[Srdjan Pavlovic] came across this problem first hand when he visited his friend and learned about their six-year-old son with hearing loss since birth. The parents said their child will not be disturbed by loud noises at night since the external unit of his cochlear implant is removed each night. [Srdjan] then started work on building the Vibhear – an assistive hearing device to be used when the main hearing aid is removed or not working. It is a low-cost arm-band that provides a vibratory signal in response to high ambient noises.
The main components are a microphone, amplifier, microcontroller and vibration motor powered by a LiPo battery through a boost converter/charger. An RTC module allows setting up daily wake up alarms. It’s currently prototyped around the Arduino, but the next iteration will use a specialized DSP which can be programmed to perform signal processing operations on input sound. This will allow identification of specific sounds such as car horns, barking dogs, smoke alarms or emergency sirens.
[Srdjan] is in the process of choosing components for his next iteration, so if you have any recommendations to help him choose the microcontroller, power supply controller or other parts, do let him know via comments below.
A person who is deaf can’t hear sound, but that doesn’t mean they can’t feel vibrations. For his Hackaday Prize entry, [Alex Hunt] is developing the Shakelet, a vibrating wristband for that notifies hearing impaired people about telephones, doorbells, and other sound alerts.
To tackle the difficulty of discriminating between the different sounds from different sources, [Alex’s] wants to attach little sound sensors directly to the sound emitting devices. The sensors wirelessly communicate with the wristband. If the wristband receives a trigger signal from one of the sensors, it alerts the wearer by vibrating. It also shows which device triggered the alert by flashing an RGB LED in a certain color. A first breadboard prototype of his idea confirmed the feasibility of the concept.
After solving a few minor problems with the sensitivity of the sensors, [Alex] now has a working prototype. The wristband features a pager motor and is controlled by an ATMEGA168. Two NRF24L01+ 2.4 GHz wireless transceiver modules take care of the communication. The sound sensors run on the smaller ATTiny85 and use a piezo disc as microphone. Check out the video below, where Alex demonstrates his build:
It’s great to build projects just to do something neat, to learn; to impress friends and other hackers. It’s even better to address a real need.
I’ve worn hearing aids for 40 some years. My response to the question “Can you hear me now?” is still all too often, “No.” Because of this I heartily applaud the Aegis Acoustics Headset currently active on Kickstarter. I’m happy to see it’s blown through its goal with over a month left.
The Aegis is targeted at prevent hearing loss, primarily in teens since they use headsets so often. It’s equally applicable to adults and pre-teens. The Aegis works by limiting the sound level emitted to 85db, which is a safe level. Above that the risk of damage to the tiny hairs in the cochlea – the inner ear – increases dramatically with a 3db increase cutting the safety time in half.
Future’s So Bright I’ve Got to Wear ‘Aids
My personal experience explains why this is important. At my first professional level job as a software developer I noticed that people at the other end of the table often mumbled during meetings. Not really, because everyone else understood them fine. I needed hearing aids.
My first hearing aids were analog devices. There were three frequency bands across the audio spectrum whose volumes could be custom set for my ears — resulting in crude and limited improvements in what I could hear. My current hearing aids are technological marvels of digital signal processing with a multitude of algorithms the audiologist can use to help me hear better. They even coordinate their actions by communicating between themselves.
I still need to ask people to repeat what they say at times. But who doesn’t? I had a successful career despite my loss. But it is still a royal pain-in-the-butt to miss out on one-third of the dialog in a movie, to not go to a local coffee house because I won’t understand the lyrics or comments by the musicians, and miss out on all the other small parts of life along these lines.
Hacking for Hearing
There are a range of areas where hackers could contribute and not just in assisting individuals, like myself, who personally gain from technological assistance.
Consider how the cell phone improved communications in developing countries. Using radio communications the countries avoided the need to string thousands of miles of wires. That saved the expense and the decades of construction time. It’s easier to get cell phone service than water in some locations. It’s important to notice that it didn’t come about because of a big plan. It came about as an unseen consequence of a technical development.
“We can rebuild him…we have the technology” is from the opening of an old TV series and movies, “The 6 Million Dollar Man” and has found it’s place in the pop-culture vocabulary. But it rings true. We have the technology. We have the tools. We have the expertise. We’re hackers and builders. We and the technology are all over the place. We’re a solution looking for a problem.
Devices that Extend the Body
All signs point to a coming revolution of devices that protect our bodies and make them work better. The 2015 Hackaday Prize theme is Build Something That Matters and that sentiment is obviously taking hold throughout the hardware hacker movement. The Aegis headphones I mentioned above are one example of preventive devices, but look around and there are many more like the UV-Badge which gives you feedback on safe levels of sunlight for your skin.
Surely we’re going to see further augmentation for the devices that help restore function. Wearables are all the rage, how long will it be before your smartwatch notification functions make it into my hearing aids? Imagine the improvements we will see in custom hearing profiles born of that smartphone-hearing aid connection. The foundations of this are user-controlled profile switching which is already in place for apps like Belltone’s HearPlus. If the advanced electronics in the smartphone can build a better noise profile and transfer it to the hearing aid my visits to the coffee shop just might get a lot better. And this doesn’t mean the devices need to look the same either. I love the Design Affairs Studio hearing aid concept that is shown at the top of this article. Hardware can be a status symbol after all.
As you look toward your next big hack, roll these concepts around in your mind. The tools, software, and talent have never been easier to connect for our group of citizen scientists who are hacking in basements and garages. It’s exciting to think about the change we can affect using the skills honed over the past decades of this hardware enlightenment we’re all living.
We’re going to straight out agree with [Pete] on how surprisingly quiet doorbells are now a days, and if we had it our way we would put his Lunkenheimer train whistle doorbell in every home*. The setup he uses is surprisingly simple, opting for a pre-built wireless doorbell that signals a microcontroller which in turn drives a relay and solenoid. While he does include a video, we felt it didn’t quite show the intensity of these whistles.
*HaD is not responsible for hearing loss and subsequent melted brains.