Piezoelectric Knock Sensor Proteus Simulation Model/ Library

 A Piezoelectric Knock Sensor is a fundamental building block for vibration detection, security alarms, and musical instrument preamps. I developed this custom model to provide a more realistic simulation than the standard Proteus components. It accurately models the capacitive discharge and resonant frequency of a standard ceramic piezo disc. Here I wanted to share this realistic Piezoelectric Knock Sensor Proteus Simulation Model/ Library that might be useful in your electronics project. 

Here is user guide and the download link is provided at the end.

How to Simulate a Piezoelectric Knock Sensor in Proteus?

In the demonstration video, the Piezoelectric Sensor is tested using Analogue Analysis and Fourier Analysis to verify its behavior as a dynamic transducer.

Key Testing Stages:

1. Circuit Assembly: The sensor is connected to an Op-Amp (TL074/Generic) configured as a buffer/amplifier. A large coupling capacitor ($100\mu\text{F}$) and a speaker (LS1) are used to visualize the output response.

2. Analogue Analysis (Time Domain):

   • By triggering the simulation, we see the characteristic damped sine wave (ringing) of a piezo element.

   • This confirms the sensor's internal properties—specifically the interaction between its internal capacitance and resistance—creating a natural decay after an "impact."

3. Fourier Analysis (Frequency Domain):

   • The test shows a sharp peak at the resonant frequency (centered around $50\text{Hz}$ in the demo).

   • This is crucial for developers to understand the frequency response and filter out unwanted noise in their embedded projects.

4. Parameter Tuning: The video shows how to adjust the Amplitude ($2\text{V}$) and Capacitance ($22\text{nF}$) within the component properties to simulate different sizes of physical piezo discs.

Potential Use Cases

• Security Systems: Detect glass breakage or door vibrations.

• Industrial: Monitoring motor vibrations for predictive maintenance.

• Musical Instruments: Creating contact microphones for guitars, violins, or drums.

• Human Interface: Using a "knock" as a digital input for microcontrollers like Arduino or ATtiny13.

How to Use the Downloadable Files

After downloading the package, follow these steps to integrate the sensor into your own Proteus projects:

1. Files Included:

• piezoelectric sensor.pdsprj: The full Proteus project file including the test circuit.

• piezoelectric.MDF: The Model Description File. This contains the electrical logic that tells Proteus how the sensor behaves.

2. Installation Steps:

1. Extract the Files: Keep the .pdsprj and .MDF files in the same folder.

2. Open the Project: Launch Proteus and open piezoelectric sensor.pdsprj.

3. Using in New Projects: * To use this sensor in your own custom schematic, you must ensure the .MDF file is accessible to Proteus (usually by keeping it in the same directory as your project or placing it in the Proteus MODELS folder).

   • If you encounter a "Model Not Found" error, right-click the sensor, go to Edit Properties, and ensure the Model File field points to piezoelectric.MDF.

3. Simulation Tips:

• Interactive Testing: Use the Spacebar or the Simulate Graph option (Right-click on the Analogue Analysis graph) to see the waveform.

• Sensitivity: Adjust the AMPLITUDE property in the sensor settings to simulate harder or softer "knocks."

Related Tutorials

• How to use Piezoelectric Transducer with Arduino
• How to detect sound levels with Arduino
• How ky-038 sound sensor works