Leobot Guides, Tutorials & Projects

This tutorial is a detailed, practical guide to using the Reed Sensor Module (MagSwitch) (Leobot Product #202) for magnetic detection: door/window state sensing, limit switches, proximity triggers, and simple RPM/tachometer inputs. You’ll learn what a reed switch actually is (a tiny sealed glass switch), how the module is typically wired (digital output + indicator LED), how to read it reliably on Arduino/ESP32 (including debounce and noise filtering), and how to mount magnets correctly so you get a stable, repeatable trigger every time.

This tutorial is a detailed, practical guide to using the USB Power Bank Module</strong> (Leobot Product #12659) to build a DIY rechargeable USB power source. You’ll learn how power bank modules typically work internally (battery charging + protection + 5V boost), how to connect an 18650 cell safely, what to expect from capacity claims, how to power Arduino/ESP32 projects reliably, and the real-world pitfalls: undervoltage cutoffs, inrush resets, “why it turns off at low load”, pass-through charging limits, and how to choose the right battery and wiring for stable output.

This tutorial is a detailed, practical guide to using the 1-Channel Solid State Relay (SSR) High Level Trigger (Leobot Product #1659) to switch higher-power loads from a microcontroller safely. You’ll learn what an SSR actually is (optically isolated semiconductor switching), how it differs from a mechanical relay, how to wire it correctly for common use cases (especially AC mains), what “high-level trigger” means in practice, and how to avoid classic SSR mistakes like wrong load type, overheating, leakage current surprises, and unsafe mains wiring.

This tutorial is a detailed, practical guide to using the Aluminium Shell USB 2.0 to TTL UART 5PIN Module Serial Converter (CP2102) (Leobot Product #4209) to connect your PC to microcontrollers over serial. You’ll learn what “USB-to-TTL UART” actually means (and what it does not do), correct TX/RX wiring (it’s easy to swap), how to choose 3.3V vs 5V logic safely, how to power targets (when allowed), and real workflows: Arduino serial monitor, ESP32/ESP8266 flashing, sensor debugging, boot logs, and serial terminals.

This tutorial is a detailed, practical guide to using the ENC28J60 LAN/Ethernet Network Module (25MHz) (Leobot Product #1657) to add wired Ethernet networking to microcontroller projects. You’ll learn how ENC28J60 differs from W5500/W5100 boards, correct SPI wiring (including 3.3V logic), how to bring up networking with popular Arduino libraries, how to choose DHCP vs static IP, and how to build practical applications like a simple web server, sensor data logger, and MQTT client.

This tutorial is a detailed, practical guide to using the 5mm 4-Pin RGB Tri-color LED (Common Anode) (Leobot Product #121) for color indicators, status lights, mood lighting, and DIY UI feedback. You’ll learn the exact wiring logic for common anode (it’s inverted compared to common cathode), how to choose current-limiting resistors safely, how to drive it from Arduino/ESP32 using PWM to mix colors, and when you must use transistor/MOSFET drivers for higher brightness or multiple LEDs.

This tutorial is a detailed, practical guide to using the BPW34 photodiode (Leobot Product #2798) for fast and accurate light/IR measurement. You’ll learn what makes BPW34 popular (speed + predictable behavior), how to read it the right way (photocurrent → voltage), when to use a simple resistor vs a proper <strong>transimpedance amplifier</strong>, how to reject ambient light with modulation, and how to build practical projects like beam-break sensors, optical tachometers, reflective sensors, and simple optical data links.

This tutorial is a detailed, practical guide to using the 5mm Infrared Receiver Photodiode (Leobot Product #2900) to detect infrared light for beam-break sensors, reflective sensing, optical communication, and IR beacon tracking. You’ll learn what a photodiode actually outputs (it generates a tiny current), how to read it with simple resistor circuits or a proper transimpedance amplifier (TIA), how to reduce noise and ambient light interference, and how to build robust Arduino/ESP32 firmware for thresholding, modulation detection, and fault detection.

This tutorial is a detailed, practical guide to using the Infrared (IR) LED Light (3W) (Leobot Product #4204) for illumination, night vision, optical sensors, and invisible lighting projects. You’ll learn how IR LEDs differ from visible LEDs, why a <strong>constant-current driver</strong> is mandatory at 3W, how to size a power supply, how to design a safe switching stage (MOSFET), how to mount and heatsink the LED correctly, and how to build practical projects like IR floodlights for cameras, beam-break sensors, reflective sensing, and IR beacons.

This tutorial is a detailed, practical guide to using Flexinol Actuator Nitinol Wire (0.3mm diameter, 0.5m length) (Leobot Product #4401) as a compact shape-memory alloy (SMA) actuator. You’ll learn the real physics (heat → phase change → contraction), how to drive SMA wire safely with <strong>current control</strong>, how to design the mechanical linkage (pre-tension, springs, leverage), how to avoid burning the wire, and how to build Arduino/ESP32 control circuits for on/off, PWM heating, and closed-loop actuation.

This tutorial is a detailed, practical guide to using the Flex Sensor (2.2&quot;) (Leobot Product #4148) to measure bending for robotics, wearables, gesture control, and mechanical feedback. You’ll learn what a flex sensor actually outputs (it’s a variable resistor), how to wire it safely with a voltage divider, how to read it accurately with Arduino/ESP32 ADCs, how to calibrate it to a bend angle (or “bend amount”), and how to build robust code with smoothing, deadbands, and fault detection.

This tutorial is a detailed, practical guide to using the 28kHz / 60W Ultrasonic Transducer (Cavitation Cleaner type) (Tutorial/Product Ref #1110) to build or repair an ultrasonic cleaning system. You’ll learn how ultrasonic cleaning works, what changes at 28kHz compared to 40kHz, what electronics you need to drive a 60W transducer safely, how to mount it to a stainless tank for effective energy transfer, and how to avoid common failures (detuning, overheating, glue/bond failure, and driver MOSFET blow-ups).

This tutorial is a detailed, practical guide to using the 40kHz / 50W Ultrasonic Transducer (Cavitation Cleaner type) (Leobot Product #4281) to build or repair an ultrasonic cleaning system. You’ll learn what cavitation is, why frequency matters (40kHz vs higher), what electronics you need to drive the transducer safely, how to mount it to a tank for efficient energy transfer, how to avoid common failures (overheating, detuning, glue failure), and how to design a robust DIY ultrasonic cleaner with timers, temperature monitoring, and safety interlocks.

This tutorial is a detailed, practical guide to using the Immersible Throw-In Pressure Sensor (Leobot Product #5148) to measure liquid level by sensing hydrostatic pressure. You’ll learn how “throw-in” level sensors work, the common output types (0–10V, 4–20mA, I²C/RS485 variants), how to power them safely, how to convert pressure to water depth, how to calibrate zero/span, and how to build robust Arduino/ESP32 logic for tank level monitoring, pump control, and alarm thresholds.

This tutorial is a detailed, practical guide to using the Mini Projector Front Surface Reflector / Mirror (114×57.5×2mm) (Leobot Product #1597). You’ll learn what makes a front-surface mirror different from a normal household mirror, why it’s used in projectors and precision optics, how to mount it without bending/warping the reflective surface, and how to use it in practical DIY projects like beam steering, periscopes, optical path folding, and simple scanner/galvo experiments.

This tutorial is a detailed, practical guide to using the Right Angle Prism (25×25mm, K9 Optical Glass) (Leobot Product #1593) in real optics builds. You’ll learn what a right-angle prism actually does, how it can behave like a near-perfect “mirror” using total internal reflection (TIR), how to bend a beam by 90° (or 180° in some configurations), how to mount it without chipping/scratching the faces, and how to build projects like a simple prism periscope, beam steering systems, and robust alignment references.

This tutorial is a detailed, practical guide to using the Optical Glass Cube Dichroic Dispersion Beam Splitter Prism (15×15×15mm, 50:50 split ratio) (Leobot Product #1598). You’ll learn what a cube beam splitter actually does (splits one beam into two or combines two into one), what “50:50” means in real life, how polarization and wavelength can change the split, how to mount and align the cube without damaging the optical faces, and how to build useful projects like interferometer demos, dual-sensor taps, and beam sampling.

This tutorial is a detailed, practical guide to using the Laser Beam Combiner Cube Prism (405nm–450nm) (Leobot Product #529) to combine two blue/violet laser beams into one output beam path. You’ll learn what this cube actually does, how to mount and align it without scratching it, how to set up a two-laser combiner rig step-by-step, what limits you’ll hit in real life (losses, polarization, beam shape), and why the listing warns about <strong>cooling above ~5W to avoid damage.

This tutorial is a detailed, practical guide to using the Round Double Convex Lens Magnifier (Optical Glass) – 24mm (Leobot Product #561) in hobby optics and STEM experiments. You’ll learn what a double convex lens is, how to find its focal length with a simple sunlight/LED method, what “magnification” really means in practice, how to mount and clean a lens without scratching it, and how to use it for real projects like small magnifiers, beam focusing, LED collimation tests, and simple image projection.

This tutorial is a detailed, practical guide to using the Triangular Prism (5cm) (Leobot Product #531) for hands-on optics experiments. You’ll learn what a triangular prism actually does (refraction, dispersion, and beam deviation), how to handle and mount it without scratching optical surfaces, how to run simple but impressive experiments (rainbow splitting, measuring refractive index, total internal reflection), and how to build useful projects like a basic spectroscope and beam-steering setups.

This tutorial is a detailed, practical guide to using the HC-SR501 Adjustable Pyroelectric Infrared (PIR) Motion Sensor Module (Leobot Product #1616) for motion-triggered projects. You will learn what PIR sensors actually detect (changes in IR heat patterns), how to wire it correctly, how to tune the sensitivity (range) and delay time, how to use the jumper for repeatable (retrigger) vs non-repeatable modes, and how to write robust Arduino code that avoids false triggers and noisy outputs.

This tutorial is a detailed, practical guide to using the Universal IR Infrared Sensor Receiver Module (KY-022) (Leobot Product #225) to receive and decode infrared remote-control signals with Arduino/ESP-style projects. You’ll learn what the module actually outputs (demodulated digital pulses), how to wire it correctly, how to identify your remote’s button codes, how to build “remote-controlled” projects (LEDs, relays, menus), and how to avoid the most common problems: short range, random triggers, and noisy environments.

This tutorial is a detailed, practical guide to using the USB Power Supply 18650 Lithium Battery BMS for Arduino (Leobot Product #1590) as a compact, rechargeable power source for Arduino and other microcontrollers. You’ll learn what this module actually is (charger + protection + boost + regulated outputs), how to wire an 18650 safely, how to use the Type-A USB 5V output and the 3V outputs, what the 0.5A charging spec implies for runtime, and how to add basic battery monitoring so your projects don’t die unexpectedly.

A servo horn is the mechanical adapter between the servo’s internal gear train and your project. It attaches to the servo’s output spline and provides holes/threads to mount your wheel, bracket, arm, or linkage. Metal hub horns are popular for MG995/MG996R because these servos are often used in higher-torque builds where plastic horns can flex or strip.