SkiSense is a versatile low-power, multi-sensor wireless data acquisition platform designed for real-time recording and performance analysis in winter sports such as ski jumping. It can be integrated into sports equipment, such a ski goggle, to provide situational insights into biomechanical processes.
At its core, SkiSense uses the Nordic Semiconductor nRF5340, featuring dual ARM Cortex-M33 cores, Bluetooth Low Energy (BLE), 1 MB Flash, and 512 KB RAM. The MCU is integrated into the u-blox NORA-B100 module, which provides a U.FL connector for flexible antenna placement. Further, it provides the following key features:
- Time synchronization and positioning enables synchronizes multi-node data collection
- Enables long-term data logging by adding a micrSD card
- Wireless data offloading or streaming
- Intuitive user interaction through piezo buzzer, and RGB LED
- Digital interface to expand the system for specific applications
- Compact and lightweight design, measuring 52 × 20 × 8 mm, weighing 6.75 gram
SkiSense integrates multiple sensing, navigation, and storage components on a compact form factor which is built of the key components, listed below:
- BME688 - Environmental Gas & Climate Sensor
- LSM303AGR – 3-Axis Accelerometer & Magnetometer
- LSM6DSV16BX – 6-axis IMU with embedded sensor fusion
- MAX-M10S - Ultra-low-power GNSS receiver
- nPM1300 – Power Management IC
- SML-LX0404SIUPGUSB - RGB LED
- VIASTON-3580 - Piezo Buzzer
- microSD Card Connector - Add and lock microSD card for data logging
- Extension Header - 7-pos pin header with 4x data lines, 1x main power, 2x ground
A detailed high livel block diagram together with the indictaion of the specifid sensor placement is shown below.
Skisense's printed circuit board (PCB) is built of 4 Layers with a total board thichness of 1.6mm. Further informations about the PCB can be found here:
| File | Content |
|---|---|
| skisense_schematics.pdf | Schematics of SkiSense |
| skisense_3d.pdf | 3D model of the SkiSense hardware as 3D-pdf for visualization |
| skisense.step | 3D model of the SkiSense hardware as .step for mechanical design |
| skisense_BOM.xlsx | Bill of Material of SkiSense |
| Manufacturing_files | Fonder containing detailed fabrication information about the pcb (thickness, dimensions and defined layer stack) as well as gerber files. |
| skisense_complete.pdf | The complete documentation contains all files above, excluding the 3D-PDF |
The firmware for the SkiSense wireless data-acquisition platform is built on the Zephyr RTOS and provides robust, time-synchronized multi-sensor logging for ski jumping and related biomechanical applications.
It implements a high-reliability data-logger tailored for sports and biomechanics research and supports data collection from multiple onboard and external sensors, with buffered storage to an SD card for offline analysis.
A detailed firmware description including installation guide can be found here
SkiSense has been integrated into uvex evident attract a ski goggle. The high-level block diagram as well as the goggle itself can be seen below. The mechanical lid to pretect the electronics as well as the firmare are opensourced in this repository. Specifically, the ski goggle firmware supports the following key functionalities:
- Time synchronization via GNSS with 1 Hz updates
- 3D position retrieval from GNSS at 10 Hz
- 3D accelerometer and 3D gyroscope data acquisition at 120 Hz
- Continuous data logging to a microSD card
This repository contains the following folders:
- doc: Contains the document and pictures of this repository.
- fw: This folder contains contains the SkiSense's frimware written in Zephyr RTOS. Its installation guide for the fimware can be found here.
- hw: It contains the electrical and mechanical design files used for SkiSense and its applications.
The following people contributed to SkiSense:
Lukas Schulthess (Firmware, Hardware, Open-Sourcing)
Christoph Leitner (Project Lead, Conceptualization)
We thank all supporters that contributed to SkiSense:
Serin Huber (Firmware, Ski Goggle)
Fabian Pleisch (Firmware, timestamping)
Philipp Schilk (Firmware)
Silvano Cortesi (Firmware)
A detailed changelog is available in the CHANGELOG.md file, documenting major updates and design revisions for each board.
All licenses used in this repository are licated in the LICENSES folder.
Unless specified otherwise in the respective file headers, all code checked into this repository is made available under a permissive license.
- Most software sources are licensed under the Apache-2.0 license.
- third party files located in the
firmware/third_party/directory are as well licensed under the Apache 2.0 license. - Hardware located under
hardware/are lincense under the Solderpad Hardware License v0.51 license. - Markdown, JSON, text files, pictures, and PDFs are licensed under the Creative Commons Attribution 4.0 International license (CC BY 4.0).