Arduino circuits provide a fantastic prototyping platform for both hobbyists and engineers. Arduino shields can be useful for heightening an Arduino’s complexity, but, sometimes, they are just not enough. In this blog post, we will look at 10 Arduino addon modules and circuits!
The ultrasonic distance module is a module that does one thing, yet is incredibly useful in many different projects. When a trigger pulse is sent to the module, it emits an ultrasonic pulse that reflects off a nearby object, and an ultrasonic receiver detects this reflection. Knowing the speed of sound and the time delay between the transmission and reception, it can determine the distance to that object. This is useful for many projects, including robotics, distance measurement, tracking, and even bat detection (since bats emit ultrasonic clicks).
The DHT11 is one of the most popular environmental sensors available for microcontroller projects, thanks to its size, price, and ease of use. Using a single wire for data transmission, the DHT11 can measure both temperature and humidity with 1° C and 1% RH accuracy. Such a sensor can be used for environmental checking, greenhouses, RC monitoring vehicles, and weather stations.
Many projects take advantage of motors, both standard brushed DC motors and stepper motors. Controlling such devices can be tricky, especially with their typically high current draw, so a motor driver module is a definite must-have. The L911OS is a fantastic module since it can be used to either drive two DC motors (offering forward and backward capabilities) or drive a four-wire stepper motor. Projects that can take advantage of such a low-cost module include robotic arms, RC vehicles, motion tracking systems, and mechanical devices.
Automated gardening is on the rise, and one common plant killer is lack of watering. This is why a soil hydrometer is a must-have for anyone who is planning to make gardening smart. But such sensors go beyond just gardening; they can be used to measure the conductivity of a substance, so long as the probes can be inserted in. Such modules typically have an inbuilt comparator, which can be manually set so that when the conductivity drops below a certain level, the digital output will trigger (this is useful in scenarios where only a simple ON/OFF situation is needed).
These modules are incredibly simple and useful, and they consist of both an IR LED and an IR photodiode. The IR LED emits IR light, which hits nearby objects, and, if the object is close enough, the IR photodiode will be able to detect the reflected IR light. This can be used in many scenarios, including obstacle avoidance, basic object detection, and even reading data on paper, which is marked with black and white patterns (since black ink has very absorbent properties).
Color detection may sound rather limited and/or pointless, but the number of projects that can take advantage of such a module is greater than you may realise. Color detection can be used to determine the color of something in color organizing machines. Some have made machines that arrange Skittles by color, in an effort to avoid certain flavors, while others have used such machines to organize cards and paper. But color detection could be used to identify much more, including product quality and paint colors.
Makers can only get so far without including some kind of display to their project. Displays can provide incredible amounts of information to the user, as well as create a friendly, interactive experience. But more modern display modules also incorporate touch screens, which can help reduce the number of I/O needed thanks to the elimination of switches. While the module shown here is a 2.4-inch TFT with a touchscreen, there are so many other modules on the market that come in all shapes and sizes!
More advanced projects may need some sort of time tracker, and there is no better way than to do this by using an RTC (real time clock). These devices run independently of any microcontroller, they can be programmed to set the time, and they can track the current time, including the year, month, day, hour, and second. Applications for RTCs include time keeping, timed events, accurate time measurements, and file syncing.
Drones, RC planes, wearables, and controllers are all becoming incredibly advanced, and many of which, by default, require positioning data. In the past, this would come in the form of GPS, but now, this also includes acceleration and orientation with respect to the Earth’s magnetic field. This is why most cannot go without a six-axis gyroscope. They can be used in a huge range of projects, including motion tracking, obstacle avoidance, mapping, orientation, and autonomous control.
This single module is featured in so many different projects—and for good reason! This small Wi-Fi device can internet-enable just about any device that has a UART port, which includes most PIC, AVR, STM8, and Arduino devices. With just a few wires and two resistors, your projects will be able to login to web pages, upload data, download data, and sync with other devices. Applications include IoT devices, self-updating firmware, and general radio control.