Project Hub /Robotics & Autonomous Systems/Robotic Arms & Grippers/High-Power LED Stroboscope

Intermediate

PIC

Project Specific

3 – 6 Hours

Partial Kit

High-Power LED Stroboscope

A microcontroller-based high-power LED stroboscope designed to measure the rotational speed of fans, motors, and other rotating objects accurately using flashing light pulses.

Originally published on ElectronicsForU

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

10pcs - 220 ohm 1/4 W Resistor Set Rs. 39.00
2-Slot 18650 Holder with Protective Cover and On/Off Switch – Case Rs. 109.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

This list includes a generic resistor set as a placeholder — it is not matched to the exact value or part number this circuit needs. The correct one is specified on the original source page linked above; check it before buying.

We don't carry yet: PIC Microcontroller
Voltage Regulator IC (7805 / LM317 / 1117)
7-Segment Display
Transistors (BC547 / 2N2222 / TIP / MOSFET)
Potentiometer / Trimpot
Thyristor / SCR / Triac / Varistor / Fuse
Custom PCB / PCB Fab

Browse all components

How It Works

The High-Power LED Stroboscope project is centered around a PIC16F73 microcontroller, which acts as the core processing and timing unit for generating precise flashing light pulses. Power is supplied and regulated to a stable 5-volt level using a 7805 voltage regulator (IC2) to ensure the logic circuitry operates reliably. User interaction and parameter adjustments are handled via switches (S2, S3, S4) and a multi-turn trimpot (VR1), allowing the operator to control the flash frequency or settings. The microcontroller processes these inputs and drives a MOSFET (T5) along with other discrete transistors and resistors. This MOSFET acts as a high-speed, high-current electronic switch capable of rapidly pulsing the high-power LED (LED2) with short bursts of intense light. By synchronizing the frequency of these LED flashes with the rotation speed of a moving object, the target appears visually stationary due to the persistence of vision. Additionally, a three-digit common anode 7-segment display (KLT363, DIS1) is integrated into the circuit to provide real-time visual feedback of the operational parameters, such as frequency or speed settings, directly to the user.

Why Build This

Measure rotational speeds of motors, fans, and industrial machinery accurately without physical contact using optical stroboscopic principles.

Calculate induction motor slip and analyze dynamic mechanical behaviors in undergraduate laboratory setups.

Gain practical experience designing microcontroller-driven high-current switching circuits using MOSFETs and multi-digit 7-segment displays.

Real-World Application

Measuring rotational speeds of motors, fans, and industrial machinery, as well as calculating induction motor slip.

Skills You'll Learn

Microcontroller firmware operation

power regulation design

high-current MOSFET switching

multi-digit 7-segment display multiplexing

analog input conditioning with trimpots

Safety Precautions

No specific precautions noted for this build — always follow general electronics safety practices.

Frequently Asked Questions

Why is a MOSFET used instead of a standard transistor for the LED?

A MOSFET (T5) is chosen because it can handle the high-current switching demands of a high-power LED stroboscope rapidly and efficiently with minimal thermal loss.

What is the purpose of the 7805 voltage regulator in this circuit?

The 7805 regulator (IC2) steps down the incoming power supply to a steady 5 volts, protecting the PIC16F73 microcontroller and logic components from voltage spikes.

How does the stroboscope measure rotational speed?

By adjusting the flash frequency of the high-power LED to match the RPM of a rotating object, the object is illuminated only once per revolution, making it appear stationary.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

PRJ-00180