Arduino and phyphox

Overview

Most astro-lab.app experiments run directly on a smartphone. But smartphone sensors vary widely in accuracy and sampling rate, and phyphox cannot access the iPhone's light sensor. The original Arduino Nano 33 BLE Sense offers a standardised set of onboard sensors that connect to the phyphox app via Bluetooth.

This guide walks through the setup: flashing the firmware onto the Arduino, adding the sensor experiments to your smartphone, and pairing the two devices. The firmware and experiments come from the curious-signals-phyphox repository; a live preview that works without hardware is at sebastianspicker.github.io/curious-signals-phyphox. The astro-lab experiments on this site do not use the Arduino kit; they run on phone sensors, TI SensorTags, a Bluetooth mouse or an Owon multimeter.

Developed in collaboration with Frédéric Bouquet, Université Paris-Saclay / Physics Reimagined.

Grades	7–10 (teacher preparation)
Subject	Physics, Natural Sciences
Method	Setup guide
Duration	~30–60 min first-time setup; instantaneous thereafter
Language	German, English

What You Need

Item	Link
Original Arduino Nano 33 BLE Sense (Rev2 is not supported)	docs.arduino.cc/hardware/nano-33-ble-sense
Arduino IDE (or arduino-cli with make)	arduino.cc/en/software
Firmware arduino/phyphox_ble_sense/phyphox_ble_sense.ino	github.com/sebastianspicker/curious-signals-phyphox
Sensor experiments experiments/*_plot_v1-2.phyphox	same repository
Micro-USB cable + computer	—

Sensors on the Arduino Nano 33 BLE Sense

Sensor	Chip	Measures
IMU	ST LSM9DS1	Acceleration, gyroscope, magnetometer
Light / colour	Avago APDS-9960	Light and RGB colour as relative counts (not lux); proximity is not used
Barometer	ST LPS22HB	Pressure
Temperature + humidity	ST HTS221	Temperature, relative humidity

Step 1 — Prepare the Arduino

1.1 Install the Arduino IDE

Download and install the Arduino IDE from arduino.cc. Follow the installation guide for your operating system.

1.2 Get the firmware

Download the repository from GitHub and open arduino/phyphox_ble_sense/phyphox_ble_sense.ino in the Arduino IDE. The sketch uses the ArduinoBLE library.

The board advertises under the fixed name phyphox-sense. Because all boards share this name and the same UUIDs, only one board per room works.

1.3 Install the board package and libraries

The versions are pinned in arduino/toolchain.json. In the Arduino IDE, go to Tools → Board → Board Manager and install:

• Arduino Mbed OS Nano Boards (arduino:mbed_nano)

Then go to Tools → Manage Libraries and install:

• ArduinoBLE
• Arduino_LSM9DS1
• Arduino_HTS221
• Arduino_LPS22HB
• Arduino_APDS9960

Alternatively, make provision installs the pinned core and libraries with arduino-cli, and make compile verifies the installed versions and compiles the sketch.

1.4 Connect the board and select the port

Connect the Arduino to your computer via Micro-USB. In the IDE, select Tools → Board → Arduino Mbed OS Nano Boards → Arduino Nano 33 BLE. Then select the correct port under Tools → Port.

1.5 Upload the sketch

Click the upload arrow (top-left) to compile and flash the sketch. Wait for "Upload complete" in the IDE status bar. Close the Arduino IDE.

There is no status LED or serial message: if Bluetooth initialisation fails, the sketch simply stops.

Step 2 — Prepare the Smartphone

2.1 Install phyphox

Download phyphox free from the Google Play Store (Android) or Apple App Store (iOS).

2.2 Add the experiments to phyphox

Copy one of the experiments/*_plot_v1-2.phyphox files to your phone or tablet and open it in phyphox.

Step 3 — Connect and Measure

3.1 Power the Arduino

The board runs from USB or from the VIN pin. As a suggestion, a battery pack can be used for mobile experiments, provided it matches the VIN voltage range in the Arduino documentation.

3.2 Pair with phyphox

Enable Bluetooth on the smartphone. Open an experiment — phyphox searches for nearby Bluetooth devices automatically. Select phyphox-sense.

3.3 Start measuring

Tap the play button in phyphox to start. Each experiment selects one sensor mode and shows the corresponding channels.

The Seven Sensor Experiments

Experiment file	Measurement
accelerometer_plot_v1-2.phyphox	Acceleration x, y, z, magnitude
gyroscope_plot_v1-2.phyphox	Angular velocity x, y, z, magnitude
magnetometer_plot_v1-2.phyphox	Magnetic field x, y, z, magnitude
pressure_plot_v1-2.phyphox	Pressure (kPa)
temperature_plot_v1-2.phyphox	Temperature and humidity
light_plot_v1-2.phyphox	Light and RGB as relative counts (clear, red, green, blue)
analog_input_plot_v1-2.phyphox	Analog inputs A0, A1, A2

How the Communication Works

The firmware advertises as phyphox-sense and sends five float32 values per Bluetooth notification: the device time and four mode-dependent channels. Each experiment writes the mode it needs to a config characteristic, and the board reads only the sensors for that mode. Channels a mode cannot produce are sent as NaN. Notifications are sent at most every 50 ms.

Related Resource

English and French step-by-step guide: hebergement.universite-paris-saclay.fr/supraconductivite/projet/arduino_nano/