# Trying to find/build a transmitter and vibrating/beeping receiver for a blind person to find home

#### bkonkel

Joined Dec 14, 2018
6
My father is fully blind and has been having issues knowing which direction to walk when the bus/cab/uber drops him off near home.

I would like to find or build him a transmitter or similar device which can be permanently plugged in at his house, and then some type of portable receiver which he can carry with him. Ideally, the receiver would be easy to use and could just buzz or beep when its pointed towards home. (bonus points if it could have some alert when he's near the steps)

I'm pretty handy but not sure where to start on this. I've googled around for some commercially available solution but can only find GPS devices for people lost in the woods etc.

Any suggestions?

Thank you!

#### BarryTron

Joined Nov 18, 2018
76
Probably a good idea to indicate the distance from bus to home, and any obstructions between.

If you do not want to use GPS you can try an Arduino with a transmitter/receiver module, and a compass module.

Compass testing:

If he is always dropped off at same location and it's a straight line to home, you can probably get away with just the compass. Alternatively you can have the Arduino programmed for him to indicate the location (preset locations) and the compass will provide the orientation (like Jack Sparrow compass).

Just some ideas to get you started, may not be the best, but hope its helpful

#### MrChips

Joined Oct 2, 2009
20,309
Welcome to AAC!

Sounds like a great project.

I would propose a different solution that uses GPS and a digital compass and removes the need for a transmitter.
The handheld, battery powered unit would have an ON/OFF switch. The user can leave it off and only has to turn it on when needed.
You can set it up with, let us say, three "location" buttons. Each button has been programmed for a specific geographic location.
When one presses the desired button, an audible tone or beep will indicate which direction to point the device towards the chosen destination.

This project requires microcontroller programming skills at a medium to advanced level.
Better still, one can create an app for a smart phone to do this. You may want to check if it doesn't already exist.

#### bkonkel

Joined Dec 14, 2018
6
Thanks BarryTron,

He is usually dropped off probably within 100 of the house (200 tops). It's not always in the same place, he could be on either side of the street, east or west from the house etc., and he doesn't really have a good way of orienting himself. As far as obstructions:nothing substantial...cars in the street and maybe some low hanging branches.

#### bkonkel

Joined Dec 14, 2018
6
Thanks Mr Chips,

My concern with a GPS based solution was accuracy.. I should mention he's in a townhouse, so if he is 10 feet the east or west he will be at the steps of another house. Would this solution be able to direct him accurately enough (i.e. within a few feet?)

#### MrSoftware

Joined Oct 29, 2013
1,676
If you must use a transmitter/receiver then check out LoRa, this guy does a pretty good range demo:

But I agree something with GPS and a compass might be the way to go. Differential GPS is extremely accurate, but I don't know if that is an option in your case: https://en.wikipedia.org/wiki/Differential_GPS

Alternatively you could use a beacon of some kind.

#### BarryTron

Joined Nov 18, 2018
76
Thanks Mr Chips,

He is usually dropped off probably within 100 of the house (200 tops). It's not always in the same place, he could be on either side of the street, east or west from the house etc., and he doesn't really have a good way of orienting himself. As far as obstructions:nothing substantial...cars in the street and maybe some low hanging branches.

My concern with a GPS based solution was accuracy.. I should mention he's in a townhouse, so if he is 10 feet the east or west he will be at the steps of another house. Would this solution be able to direct him accurately enough (i.e. within a few feet?)
1. How is his hearing? As he gets closer the radio signal can send a signal to the house and a speaker at the door can play a sound that he can use as a guide.
2. Are the drop-off locations consistent? Can he direct the uber to drop him off say at a designated location (traffic light, street sign . . .)

#### bkonkel

Joined Dec 14, 2018
6
Thank you Mr Software,

I hadn't heard of differential GPS. I'm definitely open the DGPS/digital compass solution. What kind of equipment would I need to set this up?

#### bkonkel

Joined Dec 14, 2018
6
Mr. Chips,

1. His hearing is okay. He's about 70 (has been fully blind since 18), and struggles a bit with high pitch noises. I was thinking something kind of similar, I think this would be a great idea. Kind of the equivalent of hitting the honk button on your keys when you can't find your car. Do you have any suggestions for a smart way to do this?
2. The drop off locations are semi-consistent.. Ideally the driver will drop him off directly in front of the house (it is on a one way street, so the house should always be to his right). Occasionally they drop him at some random location elsewhere on the block. Dropping him off at the corner would provide some consistency, but unfortunately he has trouble walking so its best to avoid having to routinely walk even that short distance.

Huge thanks again to you and everyone else for helping out with this issue

#### BarryTron

Joined Nov 18, 2018
76
Mr. Chips,

1. His hearing is okay. He's about 70 (has been fully blind since 18), and struggles a bit with high pitch noises. I was thinking something kind of similar, I think this would be a great idea. Kind of the equivalent of hitting the honk button on your keys when you can't find your car. Do you have any suggestions for a smart way to do this?
2. The drop off locations are semi-consistent.. Ideally the driver will drop him off directly in front of the house (it is on a one way street, so the house should always be to his right). Occasionally they drop him at some random location elsewhere on the block. Dropping him off at the corner would provide some consistency, but unfortunately he has trouble walking so its best to avoid having to routinely walk even that short distance.

Huge thanks again to you and everyone else for helping out with this issue
You can built everything for less than $5 if you feel comfortable with programming. • you will need a 433mhz transistor and receiver • and couple Arduino nano • any radio player with a speaker, may need a relay to turn on the sound device If the above is too much you can use a simple solution: wireless door bell, look for one that has 1000+ft distance with a waterproof small button, you can pick one online for$10-15. All you have to do is install the speaker outdoors and in a location nobody can see it and away from rain. When you father is dropped off all he has to do is take out the button and push it and the bell will rig. Most bells also let you program the ring duration, but he can always ring it as many times as he needs until he finds the door.

If you need something more intelligent with 1+ mile distance you can build a LoRa.

Or (cheapest solution) if you have a powerful WiFi router use an ESP32 (with this solutions you can even program to send you notifications when he activates the device and when he walks into the door (with a sensor) utilizing IFTTT.

As you can see many options are available to you, it's just a matter of what you feel comfortable with and what you are capable and willing to learn.

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#### MrSoftware

Joined Oct 29, 2013
1,676
The remote control bell idea is the simplest, if it will work. I think you need to choose a target range so you can start narrowing down the choices.

I'm not sure what's needed for DGPS, I've never used it myself but I know they use it for things that need to be very precise.

#### bkonkel

Joined Dec 14, 2018
6
The remote control bell will be a good end-point solution for when he's within earshot of the house.

To get him close enough, I'm thinking the GPS with compass solution will be great. I'm rethinking the smartphone suggestion..he can't really use the touch screen, but maybe I can set it up so he uses Siri to turn on an app that I'll code which uses the phones compass and GPS to vibrate when it's pointed towards the house.

Is there any way to upgrade the GPS on an iphone to DGPS or WAAS?

#### MrSoftware

Joined Oct 29, 2013
1,676
I doubt you could easy upgrade any hardware on an iPhone. Maybe you could use geofencing to control a beeper at the front door. i.e. when he gets within 100 feet of the door via GPS, the beeper at the front door starts beeping, or something along these lines. There are existing products that disable your house alarm, turn on your lights, etc.. via geofencing when you get close to home, maybe you can repurpose something off the shelf to control the beeper. Philips Hue lighting might support geofencing, maybe you can repurpose one of their lighting controls to control the beeper.

#### KeepItSimpleStupid

Joined Mar 4, 2014
3,909
I have an odd idea to add to the mix.

How about an invisible fence (think dogs) that would lead him from the property line to the house. i.e. t-shaped or walking path.

Maybe another technology to warn him when he's close tot he step.