Accessibilità

Accessibilità is a family of open source hardware and software for wheel chairs! Starting with control interfaces first with the eventual goal of producing an entire open source electrical system someone can use to build a wheel chair or retrofit an existing one with a more modular, robust, and serviceable one.
First Two Projects:

Accessibilità BlackBox : The BlackBox is a device that works just as it sounds, it will be a custom board with a microntroller that has a USB interface on one side and on the other side a modular signal output interface that will allow the BlackBox to interface with any wheel chair or similar device. The BlackBox will be able to utilize a large array of USB devices and convert their control signal data into the kind for the Wheel chair. The BlackBox will be able to be configured via a software interface or re-flashing the firmware, so that any USB device can be calibrated to work.

Open Source Hall Effect Joy Stick: Thanks to intellectual property law almost all the electronics and joysticks involved with Wheel chairs/power chairs are unable to be serviced by users or technicians. Manufactures will sometimes make the user replace their entire Joystick or sometimes the entire wheel chair, this is madness and completely unsustainable, so I'm going to attempt to put a stop to it. My plan is to develop an open source hall effect based joy stick that can be 3D printed and assembled DIY, there will be open hardware PCBs and open source software to make it all work. This project is phase two in a series of many. the First is BlackBox which aims to be both a usable piece of tech and a research platform to help develop the Joystick and other accessible interfaces.

Project Logs

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Major Update: JoyStick-HID Hat Design Completed !!
AVR • 03/12/2024 at 20:00 • 0 comments

Hey folks !! this project page hasn't been updated in a while but the project has been worked on continuously over the past 7 months or so, just nothing very notable to update on since the last update. The biggest news is the PCB design for the JoyStick-HID Hat is finished, well at least the rev 1 version of the design is done. We have done an internal design review with our engineering team and made a few tweaks and we will be fabricating prototypes very soon. Somethings have changed with the design but everything is mostly the same!
The RPi will be a version 5 instead of a 3/4 as originally planned. Instead of running a custom application on the RPi we will be using ROS2 with a few custom ROS packages running on the RPi to achieve what we wanted it to do. ROS Package for interfacing with the bluetooth battery management system built into the LiFEPoE battery and sending LED information to the JoyStick-HID hat for display to the user. A ROS package for interfacing with USB HID devices and translating the data out of them into JoyStick XY parameters and other datatypes so that users can use HID devices like keyboards/mic/Xbox controllers to control their chair or have someone else control their chair. There will be more ROS packages but we are still in the early stages of software design.

Anyways here the hardware !! Some quick specs to get things started:
- STM32F446RET6 100TQFP ARM Cortex M4 Microcontoller
- ARM Cortex M Serial Debu Interface/connector for in system programming and development - MAX3535ECWI+T RS485 Transceiver for communicating with main motor controller
- D24V22F5 2.5A 5VDC Voltage Regulator Module
- D24V22F3 2.5A 3.3VDC Voltage Regulator Module
- D24V22F12 2.5A 12VDC Voltage Regulator Module
- 24V Power Input with High Current Pheonix Contact Connector
- 12V Power output with High current Phoenix Contact Connector
- Rapsberry Pi 5 Running ROS2, directly power via header from 5VDC rail
- 8 Debug LEDs for STM32F446RET6
- 8 Debug LEDs for RPi 5
- Onboard Battery for STM32F446RET6 RealTime Clock
- Interface for JoyStick, JH-D202X-R2/R4 Joystick 5K https://protosupplies.com/product/jh-d202x-r2-r4-joystick-5k/
- Interface for two Rotary Switches
- Interface for 8 Momentary swiches/buttons
- Interface for LED driver board, this additional board drives LEDs in the arm wrest indicating battery level and current set speed
- STM32 will run custom FreeRTOS or ROS-Micro more to follow

This hat is intended as a developmental platform that can function in the field, it has all the features needed to control the wheel chair with additional feature that will make software development easier. The final version will be much simpler and low cost, this is only the beginning.

And of course the moment you've been waiting for ! Renders of the PCB !!
2D Render:
3D Renders:
That's all for now! More to follow! Thanks for your continued support of my open source projects !
WHAT IS UP HACKADAY !? ITS BEEN A WHILE LETS UPDATE
AVR • 08/02/2023 at 18:13 • 0 comments

This project has sat on the backburner for quite sometime but I have been thinking about it alot over the last few months and in the last couple of days I have completely overhauled my approach and developed a complete electrical system architecture for an open source wheel chair. We are going to prototype this system and graft it to an existing wheelchair owned and operated by our fearless leader Tom !

A Block Diagram says a thousand words as I've always said, so here we go !! Here is the overall architecture of the system !!

To begin with an electric wheelchair electrical system isn't super complicated to begin with in terms of the physical hardware (custom safety rated firmware for all the embedded devices in the system is the biggest challenge), I distilled down the group discussions we have been having amongst our team and boiled it down to the architecture in the diagram.
You will notice that the biggest change there is no mention of the USB HID Black box device I was originally going to develop, I decided that I still want to do that, but I would rather make a custom Joystick shield for the Raspberry Pi that has the Joystick module and all the other controls/indicators the wheelchair user will need to operate their chair but also have the ability to interface with any USB HID device at the same time. This will allow use to build a traditional electric wheel chair control interface, but also allow us to audition and test many other off the shelf devices and explore what we can do with them for potential users. This is effectively going to be a complicated research platform in its first iteration and as we go I hope to develop it down into a completely integrated, robust, fully embedded RTOS based system with no Linux SoC require.

The overall architecture hinges on two pieces of custom hardware, and the rest are off the shelf components. A cool guy named James is designing a custom motor controller that will be able to driver all the different motors in the chair from a single PCB. The other piece of custom hardware is the Joystick/USB HID Wheelchair controller research platform, an RPi Hat that contains all the standard wheelchair controls, with the RPi being used for USB interfacing and Bluetooth interfacing. The Joystick Hat will communicate with the Motor controller via RS485, the motor controller will also function as the power distribution board and send the bus voltage to the Joystick, the Hat board will have an integrated PSU to step down the bus voltage for all onboard devices. The two off the shelf devices are the massive LifePoE battery with built in BMS, and the Bluetooth shunt used for monitoring and tracking the battery performance since it doesn't have any way for the BMS to report data to us.

Moving on to the main attraction !! I am designing the Joystick /USB HID hat! Like I said before and I will say it again, block diagram is worth 1000 words:

Basic Feature set:

- Classic Wheel Chair Joystick

- Dual Speed switch

- Variable speed switch (for fine tuning of speed)
- LED indicator for power/power level
- LED Indicator for Set speed
- USB configuration port, so the user can adjust all the operational parameters to their unique preferences/needs
- Optional Horn control

To make all this work I am designing a custom Hat PCB for the RPi, here is the block diagram and tech specs so far:

Tech Specs:
- RPi 3
- STM32F446RET6 ARM Cortex M4F MCU

- JH-D202X-R2/R4 5K 10K Joystick module

- Ti DCDC Converters
- Switchcraft Mechanical Switches
That's all for now !
Colloborator: The Mobility Independence Foundation
AVR • 05/20/2023 at 22:45 • 0 comments

The Mobility Independence Foundation (MIF) is a non-profit organization dedicated to promoting and supporting mobility independence for individuals with disabilities. The foundation aims to enhance the quality of life and opportunities for people with disabilities by providing them with access to adaptive vehicles and mobility equipment. By doing so, MIF seeks to empower individuals to lead independent and fulfilling lives.
https://themif.org/
The MIF was founded by my friend Thomas Quiter and I was brought on to bring my robotics and hacking experience to their organization. Please visit their website and learn about their organization, we will be doing amazing things together !!
RPi and Python Lets Go
AVR • 05/20/2023 at 22:38 • 1 comment

To make things quick and dirty easy I am developing the blackbox around the RPI Zero Wireless !! The program will be in Python, it should be sufficiently fast for this application and it will be easy to interface with lots of USB and Bluetooth devices via open source libraries very easily !! I whipped up a python script super fast to start the concept on.

Hardware:
- RPi Zero Wireless
- PSU
- USB HMI Mouse
- Header for RPi GPIO Pins
Software:
- https://github.com/adamjvr/py-rpi-hmi-pwm
I need to dig through my piles of stuff to find where my RPi zeros are but I got a few to dedicate to this project !! Take a look at the code and give me your feedback, I've never written python before but I've programmed in other languages before.
Individuals That Use Wheel Chairs We Need Your Thoughts and Opinions !
AVR • 05/16/2023 at 15:33 • 1 comment

Title says it all !! I myself am an able bodied person so I don't have the personal experience of living with a wheel chair or relying on accessibility technology. Which is why I want to hear from those who do and what they have to say, this project is open source and its meant to help as many people as possible so its important to get their voices heard and ideas integrated into the designs.