A Prototype for a Wearable Device That Detects Obstacles for Wheelchair Users.

Sensors play a fundamental role in serving as electronic elements capable of perceiving the environment around us. According to the National Institute of Bioengineering and Biomedical Imaging, sensors are tools that detect and respond to some type of input from the physical environment. The ability of sensors to capture and respond to physical, chemical or biological stimuli makes them fundamental tools in technology, so why not use them to help people with disabilities?

In accordance with the Convention on the Rights of Persons with Disabilities (2008) disability is a concept that evolves and results from the interaction between people with disabilities and barriers due to attitude and environment that prevent their full and effective participation in society.

According to the World Health Organization (2020), an estimated 1.3 billion people, or 1 in 6 people worldwide, have a disability. Of this number, about 70 million people need a wheelchair. Given this large number, it is essential to think that wheelchair users need to be independent and mobilize within various spaces, Unfortunately on many occasions the use of wheelchairs in unsuitable spaces can become complicated for users, as they may find obstacles along the way, these obstacles may be out of sight for wheelchair users. 

In this context, we developed a prototype for a wearable device that detects obstacles for wheelchair users to help and accompany them in their day to day, alerting them to the presence of obstacles and preventing accidents.

Supplies

MATERIALS - STEP 1

• 1 Protoboard
• 20 Dupont Wire Male to Male
• 2 Resistance 220 Ohms
• 1 Arduino UNO
• 1 Vibration Module
• 1 Potentiometer
• 1 Buzzer
• 1 Ultrasonic Distance Sensor
• 1 OLED Display Module

MATERIALS - STEP 2

• 2 Protoboard
• 35 Dupont Wire Male to Male
• 2 Resistance 220 Ohms
• 1 Arduino UNO
• 1 Vibration Module
• 1 Potentiometer
• 1 Buzzer
• 1 Ultrasonic Distance Sensor
• 1 OLED Display Module
• 1 Attiny44

MATERIALS - STEP 3

• PCB board
• Welding equipment
• 2 Resistance 220 Ohms
• 1 Vibration Module
• 1 Potentiometer
• 1 Buzzer
• 1 Ultrasonic Distance Sensor
• 1 OLED Display Module
• 1 Attiny44
• 1 battery module

Step 1: Prototype Using Arduino

In this step you can observe the development of the first prototype using Arduino 

1. Have all materials listed in the materials section.
2. Using the diagram shown in the image, build your circuit, we recommend using the same pins that we use in the Arduino, if you change them you must adapt the code to the new connections.
3. Download the attached code file for the circuit and run in Arduino. Don’t forget to test all components before you run the code. It is important to mention that the vibration module signal is connected to the display on the SDA pin
4. Your result should look like the attached video.

Step 2: Prototype Using Attiny44

In this step you can observe the development of the prototype using Attiny44

1. Have all materials listed in the materials section.
2. Using the diagram shown in the image, build your circuit, we recommend using check that you Attiny44 is well connected. In this case we use Arduino as the programmer, but you can replace it with a programmer of your choice.
3. Download the attached code file for the circuit and run the program. Don’t forget to test all components before you run the code.

Step 3: Prototype Using a PCB

In this step you can observe the development of the prototype using a PCB

1. To design the PCB we use the Altium software. We developed a schematic of the system. In the files part you can find the project to download it.
2. We use a machine to make PCBs where we place the attached PDF files as a guide. It can be seen in the image 1 and the final result in the image of final result.
3. On the PCB we weld the components mentioned in the materials area. It can be seen in the image 2.

Step 4: Final Product

We use a wheelchair to show it during the exhibition.

P.S. It is important to mention that we made a 3D printed cover.