BlindFly: Raspberry Pi Obstacle Avoidance for the Visually Impaired

Always Something There to Remind Me

Ya know, sometimes i end up over indulging myself to the point where i kinda lose sight of why i got into technology in the first place. which is to enhance a persons present potential and to help remedy any malfunction that their body may have endured. But sometimes i do get a reminder.

My buddy Pete is the best drummer i ever had and he’s blind. You’d be surprised at what he can do without any sight. I decided to put my brain to some use and see what he’d be able to pull off with a little help. So this is for him (and anyone else who would find this useful). I call this one: BlindFly

Basic Gear

Alright! the fun part! So you’ll need:

-The Raspberry Pi 4 – your general purpose open sourced computer of course.

Alternatively, if you want your project to be as small as possible in exchange for noticeably less processing power/speed, I’d go with:

-The Raspberry Pi Zero(with pre soldered headers)

basically your more portable kid brother to the pi3-4.

Grove Base Hat for the Raspberry Pi Zero

Grove Base Hat for the Raspberry Pi Zero from SeeedStudio

– your expansion board built to use Grove sensors, a simple plug n’ play means of using a wide array of sensors to give your machine..err “senses” to better interpret the world around it.

With its petite size and compatibility with about 60 sensors, the Grove Base Hat is a solid go-to for Raspberry Pi sensor expansion.

Next, you’ll need:

-A Grove Ultrasonic Ranger:

A small sonar module that judges distance based on the timing of the sent signal that gets reflected back to it much like a dolphin or bat. Great for obstacle avoidance.

Grove Rotary Angle Sensor:

This is used so that the user can adjust the frequency of the beeping alerts to their OWN liking. A nifty way of making this device a bit more universal/customizable/accessible to the average user.

– A TNTOR Ultra Thin Power Bank(or pretty much any usb power bank)

Portable, flat (about 3 Metro Cards thick),virtually weightless and non-invasive to most design plans WITH a built in wire and optional USB-C adaptor if your going with the Pi4. My flavor of the week.

-And finally, any USB or Bluetooth Speaker for sound effects. Bluetooth gives you more modularity though a directly connected USB speaker or Auxiliary sound tends to yield better responses.

Optional but recommended Gear

-An actual power switch can be very useful for cutting power to your Pi without having to unplug it which will save battery as well as wear n’ tear on your pis power socket.

Longer Grove Wires– depending on your overall design plan, you may want to look into alternate grove wire sizes.

Using welders goggles and a few neodymium magnets to hold the Ultrasonic Rangers in place while allowing them to be adjustable by the user.


Now as usual, whenever you do anything new with your pi, you’ll want to go into the terminal and run:

Sudo apt-get update

Sudo apt-get upgrade

-Then, use these instructions to install The Grove Base hat for the Pi Zero.


Alright! the other fun part! When your done installing and testing your unit, you’re ready to code.

I tried to make a simple, straight to the point, customizable script with enough foresight involved to make expanding your gadget’s functionality as easy as putting together Legos.

BlindFly Code in Python

Note that i turn off the device by covering the sensor itself. My subject shouldn’t have to be fiddling around for buttons.

And with this, we have a nice, practical use human obstacle avoidance system to be tweaked and modded to our hearts desire. Hell yea!

Next Steps

When your code and construction is pretty much up to spec with your purposes, it’s time to get your machine to function as independently as possible. Completely self contained and portable without being a slave to the wire…for this you can look into:

RealVNC: a lovely interface that allows you to control your electronics with your cell phone.

-And of course, Starting up your program automatically when your Pi boots up.

As usual, comment if you have any questions and feel free to like, share and Contribute if you think my cause is worthy or if you just like what i do.


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