Tremor Monitor
Problem I am trying to solve
Some of the most commonly available devices to measure body tremors come in the form of an App on the smartphones or wearable gadgets that tend to be expensive. Mostly patients suffering from Parkinson's have to make a trip to the doctor's office to follow the progression of the disease.
Goal of my project
To build a cheap and portable device that accurately measures hand tremors (eg: Parkinson’s shaking) based on the principle of piezoelectric energy (conversion of kinetic energy to electric energy).
Research
Peizo-electric sensor diagram
Since my project makes used of piezoelectric effect we need to understand what it is.
When a crystal (any solid with an orderly arrangement of molecules), undergoes mechanical stress, its uniform pattern of positive and negative charges becomes deformed, causing a net electrical charge to appear.
A piezoelectric sensor when connected to an Arduino Circuit Board can capture the pressure of contact from a finger and a program written in C++ can capture the raw data and analyze the changes in pressure.
Since Parkinson's tremor occurs when voluntary muscle activity is absent and is much higher in amplitude than Essential Tremor, the variations can be captured to detect the degree of the tremors.
Circuitry to collect input from finger
Arduino Uno boards with input sensor and output LEDs
Data collection algorithm
A baseline is first captured with Essential Tremors, when you place you gently place finger onto the piezoelectric sensor applying no pressure. The piezoelectric sensor is sensitive enough to read the pulse rate from the finger when the finger comes in contact with the piezo sensor.
Essential Tremors were measured by placing my Pointer finger on the device, after waiting 10 for readings for the Piezo sensor to calibrate. After 10 readings, the algorithm takes a baseline value, and compares it to the next 10 seconds of data in which my finger is placed on the sensor. At the end of the 10 seconds, the sum of the delta is multiplied by 100 and a score is printed
Crafted custom box to package circuit
Used Tinkercad to design box
Print box on 3 D printer Taz 6
Raised pedestal for the LEDs
Insert for finger to be placed on the touch piezo sensor
Testing of device
To be able to simulate parkinson’s tremor, I created a device which would strap on the wrist and mimic the motions of parkinson’s tremor. I checked existing designs with had a glove fitted with a motorized device that creates tremors at different frequencies
A Baseline or Essential Tremors were measured by placing Pointer finger on the device, after waiting 10 for readings for the Piezo sensor to calibrate
Simulation of Parkinson's Tremor was done by wearing the Parkinson’s simulating device and placing my pointer finger on the device
The Parkinson’s simulating device was operated at 2 different power of the motor or rotation speeds 50 power or 125 RPM (~1.25 HZ) and 100 power or 225 RPM (~2.25 HZ)
Conclusions
My goal to build an accurate, cheap and portable device to monitor Parkinson’s tremor was a success as it met following design criteria:
Cost : Aggregate Total: $52.98 (Met the constraint of $100)
Construction : Device was easy to construct because it only had four components that can be easily connected. The outer shell could be easily built using a 3D Printer.
Stable and Consistent Output : Based on my input, my device was able to produce consistent output across all the trials and samples
Simple to Use : My device is simple to use because the user only has to place their finger on the sensor and watch how the output changes relative to their input
Recognition
1st Award, Physical Science and Engineering Category
Selected participant to CSEF
Nominated to fill envelope
