Over the year, The maker community has designed several platforms to monitor vital signs with boards like Healthy Pi v4 or HeartyPatch both of which are powered by an ESP32 WiFi & Bluetooth wireless SoC.
WallySci has designed another all-in-one wireless bio-sensing platform, called E3K, that also happens to be powered by Espressif Systems ESP32 chip, and can be connected to an electromyography (EMG) sensor to capture muscle movements, an electrocardiography (ECG) sensor to measure heart activity, and/or an electroencephalography (EEG) sensor to capture brain activity. The board also has an extra connector to connect a 9-axis IMU to capture motion.
E3K main board which the company refers to as “Data Communication and Processing Unit” (DCPU) comes with the following specifications:
- Supported wireless board – ESP32-DevKitC with ESP32-D0WD-V3 dual-core 32-bit LX6 microprocessor, up to 240 MHz, Integrated 520 KB SRAM, 16 MByte SPI flash. 2.4 GHz WiFI 4, and Bluetooth 4.x/5.x connectivity
- Data acquisition – 2x 8-bit DAC with 1 to 2000 Hz sampling rate
- 1x I2C header to use with the IMU sensor module
- 6x 3-pin headers 12-bit analog pin to use with the EMG and ECG/EEG sensor modules
- 1x 5-pin header with three 12-bit analog pins to use with the EMG and ECG/EEG sensor modules
- 2x Qwiic I2C connectors
- 10-pin SPI header
- Female headers to access all ESP32 DevKitC pins
- USB – 1x micro USB 2.0 port (on ESP32 DevKitC)
- Misc – 2x LEDs, 2x buttons
- Power Supply – 3.3 to 6 V via USB or battery via 2-pin connector or through holes; On-board LiPo charging circuitry
I won’t go into the details of each sensor board but they are connected via analog inputs as shown in the specs, and take data from a cable connected to a 3.5mm (audio) jack.
The ESP32 board can be programmed with the Arduino IDE and Espressif ESP-IDF framework, and Arduino libraries, as well as MATLAB and Python APIs, are in development. WallySci wrote their own data acquisition software with the open-source E3K GUI that allows you to configure each channel and collect data without having to program the board. The source code as well as hardware schematics will be shared on Github. In the meantime, you’ll find links to the firmware and GUI, as well as sensor datasheets on WallySci website.
WallySci E3K has recently launched on Crowd Supply with a $4,000 funding goal. Rewards start at $39 with E3K DCPU with ESP32-DevKitC-32E board, but unless you plan on using your own sensor modules and electrodes, most people would likely go with the $159 E3K Combo that includes the E3K DCPU with ESP32-DevKitC-32E, one EMG sensor, two ECG/EEG sensors, and one IMU sensor, as well as one electrode cable and five electrode pads. Shipping is free to the US, and $7 to $15 to the rest of the world, with delivery expected to start on February 27, 2021.