Vibration Spectrum Lab Kit

Classes 11-12, typical ages 16–18. Age ranges vary by learner. Guided low-voltage electronics.

Activity engagement

120–180 minutes. Explore 20–35 min · Build 40–60 min · Test and discuss 60–85 min. Estimated time for building, testing and discussion.

What you need

A computer with a USB port and Arduino IDE is required and is not included. Wi-Fi/BLE experiments also require the local network or phone specified in the guide.

Included components

• Small Breadboard / Mini Solderless Board - 400 points — 1 breadboard
• Jumper Wire Combo - Male to Male, Male to Female and Female to Female Breadboard Connecting Wires (10 Qty Each) — 1 set
• Illustrated Activity Guide and Observation Sheets — 1 set
• Fitted Headers and Labelled Connection Leads — 1 set
• ESP32S 38Pin Development Board (WIFI+BLUETOOTH) — 1 controller board
• MICRO USB DATA CABLE — 1 data cable
• MPU6050 3-Axis Gyroscope/Accelerometer Sensor Module — 1 sensor module
• Inertial Sensor Mounting Plate with Screws — 1 set

What you learn

• Sampling interval determines the usable frequency range.
• Removing the mean separates gravity/bias from changing acceleration.
• A spectrum describes the measured signal, not a certified machine-health diagnosis.

Connection guide

• Supplied regulated GY-521 VCC → board USB 5 V output; GND → GND; SDA → GPIO21; SCL → GPIO22. I2C pull-ups on this breakout are 3.3 V.
• Attach the board to the supplied flat mounting plate with insulated spacers; do not short contacts against metal.

Steps to make it

1. Disconnect all power and identify the supplied part labels and pinouts before wiring.
2. Mount the sensor rigidly and upload the 100 Hz serial capture sketch.
3. Save at least 256 consecutive CSV samples for a stationary trial and a gentle periodic hand-motion trial.
4. Run the included standard-library Python analysis script on each saved CSV file.
5. Compare time spacing, estimated sample rate and the main non-DC frequency bin; repeat with a different hand-motion rate.
6. Change only the named parameter for the extension, repeat the controlled trials, save observations and disconnect power afterward.

Programming resources

Arduino IDE: install esp32 by Espressif Systems 3.x; select ESP32 Dev Module for the supplied classic WROOM board. Serial Monitor: 115200 baud. GPIO is 3.3 V only.

Libraries to install

• Adafruit MPU6050
• Adafruit Unified Sensor
• Adafruit BusIO

Download starter sketch

Download standard-library Python spectrum analysis

Test challenge

Compare a quiet baseline and two gentle periodic motions, avoiding impacts that saturate the ±2 g range.

Observation task

Capture label, timestamp spacing, sample rate, dominant frequency and spectral magnitude.

Expected result

A finite-window spectrum can reveal repeated motion; resolution is sample rate divided by sample count.

If it does not work

Export only CSV rows with the header ms,ax,ay,az. Large timing gaps or loose mounts change the result; there is no forced-vibration actuator in this kit.

Try next

Compare a rectangular window with the supplied Hann window and discuss leakage.

Use and supervision

Use only the supplied low-voltage DC parts. Disconnect power before rewiring; check polarity and labelled pinouts. No soldering or exposed mains connections. Adult guidance is recommended.

How this experiment works

Download class activity guide

Cover illustrations show component types. Functional animations explain principles and are not recorded prototype tests. Follow the supplied connection labels and pinouts.