Research Partners

eXtendable Heterogeneous Energy-Efficient Platform - EPFL X-HEEP

Sources of Funding

Wyss Center


VersaSens is a versatile wearable sensor platform. Its compact, flexible, and extendable design allows for easy customization to meet your specific needs. With VersaSens wearable sensors, bio-signals can be acquired, synchronized and processed in real time. The electronic components of VersaSens are safe and embedded in the biocompatible casings with skin-safe certified silicone, used to interface with the user's skin. Materials were chosen for optimal comfort, and to ease ethical permits applications in case of clinical tests, while the casings were designed for user-friendly experience.

The platform includes a main module equipped with a Nordic nRF5340 dual-core System on Chip (SoC), which not only processes and stores the acquired data, but also enables real-time wireless streaming of the data to a computer or mobile phone. In addition, the main board is equipped with a Power Management Unit (PMU), 8GB NAND flash, micro SD card, and an Inertial Measurement Unit (IMU). Communication between the main module and peripheral modules is through a bus using FPC and USB-C connectors. This feature allows the flexibility of many configurations by stacking the boards horizontally/vertically or placing them at different distances from each other on the user's body.

We have developed peripheral sensor modules called Heart, ExG and EDA modules. The Heart module comprises a mem microphone for measuring acoustic cardiogram (ACG) signals, an infrared thermometer for measuring skin temperature, and a MAX86178 integrated circuit (IC) analog front end for measuring electrocardiogram (ECG), photoplethysmogram (PPG), and respiration (RSP) or electrodermal activity (EDA) signals. The ExG module contains an ADS1298 analogue front end that can measure up to 8 channels of electroencephalogram (EEG), ECG and electromyogram (EMG) signals. Finally, the EDA module incorporates a MAX30001G analogue front end capable of measuring ECG, RSP/EDA signals simultaneously.

The platform includes a HEEPO module powered by the HEEPocrates SoC. This module acts as a co-processor to speed up machine and deep learning algorithms, enabling real-time inference during signal acquisition. The platform is carefully designed to balance flexibility, expandability, wearability, and compactness. Pre-designed modules offer numerous configurations, and additional sensor and co-processor modules can be added as needed.

Multiple VersaSens sensors can be worn on the body. They can communicate seamlessly and synchronize with each other to act as complementary sensors, improving the overall signal quality and fusion results.