Help needed with sensing aid gadget for a deaf person. - Page 1
Forum section: electronics / beginners

author: alexRosito
author_rank: Newbie
timestamp: January 03, 2023, 09:53:04 pm
content: A little bit of context:Grandpa has ever been a very active man. He's now reaching his 80s but still does his home chores and drives. Unfortunately, because of a stroke he lost his hearing and it's been so hard for him to know when someone rings his small apartment bell, also because he still drives, he needs some kind of aid to know when an ambulance, fire truck or police car approaches and pull over.I just came with the idea of creating some sort of a gadget that lets him sense (with a small vibrating dc motor rated 4 volts) when a sound of a bell, ambulance, etc. is present. I used an electret microphone to pick the sound and a potentiometer to adjust the frequency of the sound needed.The electret signal is then amplified by a three-stage transistor type A amplifier.As the brains of the gadget, I'm using an LM567 to lock on the selected frequency and, as you the reader already know, when the LM567 "hears" a sound with the selected frequency it latches and pulls down the output of pin 8 (open collector), that's when, using a PNP transistor as a switch, it turns the dc motor on.The issues:The gadget works very well but there are two issues that annoy me:1. The output is not a clean high or low value but there's a small ripple that turns on the dc motor (not fully but still I can feel the motor struggling to go fully on, it seems that because of the ripple pulling down the base of the PNP transistor for short periods of time the motor senses it and reacts accordingly).2. I think I've been too optimistic into believing that an electret microphone would have enough reach to "hear" the doorbell when grandpa is in the kitchen or in the bathroom.I would like your opinion on this project if I should keep looking for solutions or it's a silly idea.If you think there's hope for this project and have any ideas, please let me know. Thank you.

author: tooki
author_rank: Super Contributor
timestamp: January 04, 2023, 03:14:47 am
content: You know that modern iPhones (and iPads, and Apple Watch) do this already, with sound recognition to tell the user what the sound is?

author: alexRosito
author_rank: Newbie
timestamp: January 04, 2023, 04:12:00 am
content: Thank you tooki for your suggestion. I think it would be a good solution to the immediate problem of Grandpa and I will surely make use of it, nevertheless and because Grandpa is very, very old school he's always complaining about smartphones and how complicated it is for him to use them I thought a dedicated gadget would be ideal for him.But in the meantime, I think he eventually will get used to your solution suggestion will surely help him immediately.But still Grandpa told me that for him it is easier to have a black box with a dial where he sets the desired kind of sound. I was thinking that instead of a potentiometer to use instead a rotary resistor switch to make the selection sensitively easy for him, and also, he just wants to feel the vibrations of the dc motor in order to know what selected sound is present.You know very, very old school man.And for me, this project is the perfect excuse to learn more about sound systems, how to bias an electret microphone, amplifiers (I could use an LM386 and actually I used one in my first prototype) but since I have hundreds of jellybean transistors (as Dave Jones calls them), I rather like to use them and create a decent amplifier to use with the LM567.I'm not an expert, I consider myself a very noob hobbyist and I would like to know the opinion from experts like you to know if I'm in the right path or if I'm wasting my time and move on into another project.But the idea is to learn and at the same time help Grandpa.

author: rstofer
author_rank: Super Contributor
timestamp: January 04, 2023, 05:20:39 am
content: I hope you can find a cheaper solution with adequate response and accuracy but...A Neural Network can be trained to recognize sounds. The learning part is easy and hardware exists for the AI (Jetson Nano, among others) but I am wondering if there is a less power consuming approach without all the magic. The iPhone solution, if adequate, is going to be the fastest and cheapest.One advantage to the AI approach is discrete outputs for the various sounds. It will differentiate between a train, an ambulance and the doorbell with different and discrete outputs. When training, account for varying frequencies from the doppler effect.https://towardsdatascience.com/audio-deep-learning-made-simple-sound-classification-step-by-step-cebc936bbe5I provided a link for something I encountered during a search. I would search for 'neural network sound recognition' or something like that.I'm thinking about a 'fanny pack' to hold the hardware with a vibrator of some kind as you suggested above.It's a long climb to create the neural network if you have no background (and I don't).I found more targeted articles by searching for 'neural network ambulance siren detection'.

author: alexRosito
author_rank: Newbie
timestamp: January 04, 2023, 06:02:07 am
content: Thank you so much for your suggestion rstofer. The iPhone solution is going to be the fastest and cheaper solution for Grnadpa and I will implement it as soon as possible.I’ll be researching on the AI suggestion you have given to me. It makes a lot of sense and it could be an excellent product to develop in order to help those in need.As you said, it’s going to be a long climb but that’s what makes it interesting.Thank you.

author: rstofer
author_rank: Super Contributor
timestamp: January 04, 2023, 04:42:58 pm
content: I hope you can get the AI approach to work. It will take a lot of samples under varying conditions but it is clearly worth the effort (on a large scale). You might check into Google for their contributions to AI, they are substantial. There are a lot of paths to research.I'm a really old grandfather myself. I hope this thing works out.

author: themadhippy
author_rank: Super Contributor
timestamp: January 04, 2023, 05:56:47 pm
content: does grandad wear a hearing aid that also works with induction loops? was involved with a system a good few years back were the doorbell put a tone on an induction loop.

author: alexRosito
author_rank: Newbie
timestamp: January 04, 2023, 06:05:00 pm
content: Thanks again rstofer for your suggestion. I'll do my best. I'm also a brand-new granduncle, (I have two daughters, but it seems that they don't have any interest in being mothers) so my grandnephews will enjoy two grandparents (my brother and I).The AI approach is not trivial but is really powerful and I think that it is the way to go.I just hope to keep it as simple as possible because grandpa is a very, very old-school guy.Once again, thank you. I'll be googling your suggestions.

author: alexRosito
author_rank: Newbie
timestamp: January 04, 2023, 06:06:55 pm
content: Hi themadhippy. Thanks for asking. Unfortunately, grandpa is completely deaf, and no hearing aid works for him. Which is really sad.

author: bidrohini
author_rank: Regular Contributor
timestamp: January 07, 2023, 07:27:33 am
content: You can check these too:https://www.hackster.io/krishnatcs17/assistive-door-for-the-deaf-and-hard-of-hearing-43ff15https://ieeexplore.ieee.org/document/9777226

author: tggzzz
author_rank: Super Contributor
timestamp: January 07, 2023, 09:55:24 am
content: Quote from: alexRosito on January 04, 2023, 06:06:55 pmI'm >120dB down in one ear and 60-80dB in the other. If the "good" ear gets any worse then I'll be eligible for a cochlear implant.I assumed you couldn't teach old dogs (like me) new tricks, but the consultant said it was possible.