Cortex-Feet: Foot Neuropathy Analyzer and Blood Flow Stimulator embedded in Smart Motion Sensing Shoes designed for Diabetic Patients
What is Diabetic Neuropathy?
Diabetes is one of the major causes of illness and premature death worldwide. Diabetes causes neurovascular complications, which result in the development of high pressure areas in the feet and hands. Diabetic neuropathy causes nerve damage which can ultimately lead to amputation or ulceration. Wikipedia says vascular and neural diseases are closely related and intertwined. Blood vessels depend on normal nerve function, and nerves depend on adequate blood flow. A person with diabetic neural dysfunction would also have Microvascular dysfunction.
Is there a Treatment?
As a remedy, sending imperceptible vibrations through the feet of diabetics and stroke patients significantly improves the damaged nerves and stimulates blood flow, according to a study conducted by a biomedical engineering university in America.
Diabetic Neuropathy is a serious medical disorder and can be prevented by the early detection of abnormal pressure patterns under the foot. Although equipment to measure foot pressure distribution is available in India and elsewhere, these are still not readily accessible for a large segment of the population, are too expensive to own, and are too bulky to be portable. The foot pressure monitors are also not readily available in less developed countries which are home to many communities with a high prevalence of diabetes.
Our project is to design and build a low-cost foot pressure and foot movement analysis and blood flow stimulation system, embedded within smart footwear which a patient can wear at any place to monitor his or her foot pressure distribution to identify and diagnose foot neuropathy as early as possible.
Description The handheld touchscreen unit communicates wirelessly with the foot attached unit and collects real-time data, stores it in the memory card for analysis by a doctor at a later time. The device monitors the user foot movement using a 3-axis MEMS Accelerometer and actively looks for situations leading to foot injuries. Once the system detects an anomaly in the user’s foot pressure distribution or foot motion, it issues an alert to the handheld touchscreen device. To improve the blood flow the smart footwear has a set of miniature Vibrating Motors that stimulate the nerves by vibrating in different amplitude that can be configured individually, started and stopped by the user using the handheld touchscreen unit. The smart footwear will collect data from foot pressure sensors and foot motion sensor and periodically transfer this data to the handheld unit where it will be stored in a 2GB MicroSD memory card for future reference or for an analysis by a doctor.
In this system, the foot pressure distribution is measured by a set FlexiForce pressure sensors located on the insole of the shoe. These sensors are based on force-sensing resistors, whose resistance varies inversely with the applied force. The footwear unit measures the pressure sensor outputs and transmits the information using IEEE 802.15.4 wireless transceiver to the handheld monitoring unit. The monitoring device is equipped with a 65K Color Touchscreen TFT Display that receives the wireless data and displays the foot pressure information on color bar graph as well as store that data in the memory card.
Both the footwear unit and the handheld display unit use LPC1313, a 32-bit ARM Cortex-M3 Microcontroller from NxP Semiconductors. Apart from the application software and the device driver firmware the microcontroller also runs software such as a Graphics Library, a FAT-32 File System and an IEEE 802.15.4 Wireless Networking Protocol Stack
Software Tools Used:
Programming Language: Embedded C
Development Tool: LPCXpresso IDE (Eclipse based)
Embedded Protocols Used:
I2C, SPI, UART, IEEE 802.15.4.
Software Libraries Used:
Touchscreen Controller Driver via SPI protocol
Micro-SD Card Driver Library via SPI
IEEE 802.15.4 Wireless Protocol Stack
Digital MEMS Accelerometer Driver via I2C protocol
Cortex-M3 Peripheral Device Driver Library
CMSIS from ARM
• This project not only enables early detection but also provides treatment and prevention of Diabetic Neuropathy which is a serious medical disorder
• Equipment to measure foot pressure distribution is either too expensive to own or too bulky to be portable.
• The system design in our project is such that the sensors and actuators can be fitted within the shoe unit and the monitoring unit a simple handheld device allowing to overcome the previous drawback.
• Thus our project will be cheaper and readily available in less developed countries which are home to many communities with a high prevalence of diabetes.
• Large external memory allows the system to continuously store data from the smart shoe even for several weeks.
• Advanced Color Graphical User Interface with the help of a TFT LCD and Touchscreen Panel.
• Next generation ARM Cortex-M3 architecture is the chosen hardware platform, ideal when low power and high performance is needed.