The 37 sensor collection for Arduino is a popular kit that is available from many manufacturers. Its low cost makes it an ideal Arduino accessory but one thing that it lacks is adequate documentation. In this article will review all 37 sensors and describe what they do and how they are used. Future articles in this series will give you actual code and examples for using these sensors in your projects.
The 37 Sensors Kit for Arduino
If you done any shopping for Arduino parts and accessories you have undoubtedly run across the 37 sensor collection. This collection of Arduino interfaces is available from many different manufacturers, often at a very attractive price. But what does this actually contain and what can you do with these 37 different devices?
First of all the term “37 sensors for Arduino” is actually a bit misleading. In actual fact these devices are not all sensors, many of them are output devices and none of them are actually Arduino specific. You could use these devices easily with another microcontroller or microcomputer such as a Raspberry Pi. Nonetheless this is a great collection of low cost devices that you can use for experimenting or for creating actual products with.
I recently purchased one of these kits from a distributor in China. As is often the case the shipping time was extensive, in fact it took nearly two months for my kit to arrive. When it did finally get here I eagerly tore open the parcel and found a nicely packaged plastic box with 36 individual compartments. Each compartment held one sensor and two of the compartments had two devices inside them. While this might seem to total 38 sensors in actual fact one of them is a two piece device.
Inside the lid of the box was a rather faded photocopy with small pictures of each individual sensor, along with a short description of the device. And that was it no documentation no software of any sort package with the kit (to be fair I’ve seen some versions of this kid that actually do come with a CD which I assume contains some documentation and/or code). This is pretty well a “do it yourself you’re on your own” product!
I examined each sensor and found them all to be reasonable construction. Many of them use the common circuit board which actually makes a lot of sense, the only difference on the boards was the actual sensor itself. In many respects this is a good thing as once one learns to use one sensor it should be pretty easy to move on to the next one.
Lack of Documentation
There are quite a wide variety of devices contains inside the 37 Sensors kit, they range from simple LEDs to esoteric devices such as a “heartbeat sensor”. Needless to say I wanted to learn more so that I could start using these devices with my own Arduino designs
In many cases I found the hook up and use of the sensor to be fairly obvious they all use very simple circuit boards and I could actually see the traces and many of the components were familiar to me. There were a few however that were a bit of a mystery to me. Naturally I took to the internet to see if I could find more information regarding these different sensors.
While there is information on the internet about the sensors it’s few and far between and much of it seems to be a poor translation that is hardly readable. YouTube was another good resource, I found a few people had created some videos about using one or two of the sensors. So I decided to compile all of this information along with my own experiments so that other people wouldn’t have to go through the same thing.
Having 37 different sensors to write about would make for a very long article, which is why I’ve decided to break this into a couple of different parts. In this first article and its associated video I will go briefly over what each sensor is. Future articles and videos will go into depth about specific sensors and I’ll supply the code that you need to make them work in your Arduino projects.
37 Sensors – 8 Categories
So here they are, all 37 sensors. To make things easier I have divided them into 8 categories, and I’ll publish an article and video for each category where I’ll go into greater detail and include some Arduino code you can use with them. Here are the categories:
- Light – Devices that sense or emit light, both visible and infrared.
- Sound & Vibration – Devices that sense or emit noise and vibrations.
- Human Interaction – Any device that you need to interact with manually.
- Magnetic Fields – Devices that sense magnets or magnetic fields.
- Position Sensing – Devices that sense their physical position.
- Proximity Detection – Devices that measure the proximity of themselves to other physical objects.
- Weather – Devices that measure environmental variables like temperature, humidity etc.
- External Control – Devices that allow you to control other devices.
And here are the sensors (or devices if you prefer), arranged into the categories I defined for them:
Light sensors and emitters. These are covered in depth in Arduino 37 Sensors Part 2.
- 2-Color 3mm LED – This is a red-green 3 millimeter LED. The device includes an appropriate dropping resistor.
- 2-Color 5mm LED – Another red-green LED with a dropping resistor. This is a slightly larger 5 millimeter device.
- 7-Color Flashing LED – This unique device is a programmable LED. It can be programmed to flash in seven different colors.
- Flame Sensor – This infrared sensor is tuned to the specific wavelength of a flame.
- IR Emitter – This device transmits in the infrared wavelengths. They are commonly used in remote controls.
- IR Receiver – This is an infrared receiver device with mates with the infrared emitter. Together these would make an effective remote control or remote data link.
- Laser – This is a red laser diode, similar to the ones used in laser pointers. You need to be careful when you’re playing with this device!
- Photo Interrupter – This is an optical source-sensor assembly commonly used to measure motor rotation or the end of travel on a mechanical device.
- Photo Resistor – This is a device that is sensitive to the level of ambient light.
- RGB LED – This is a red green and blue LED in one device. Different combinations of these three colors allowed any color to be produced.
- SMD RGB LED – Another red green and blue LED, this time a surface mount device.
Sound & Vibration
Buzzers, microphones and vibration detectors. They are covered in Arduino 37 Sensors Part 3.
- Buzzer – This is a buzzer designed to be used in alarms and indicator circuits. This buzzer generates its own tone when it is triggered.
- Large Microphone – This sensor contains a microphone and has both digital and analog outputs. The digital output can be set the trigger on a certain sound threshold.
- Passive Buzzer – The passive buzzer is more like a small speaker that is capable of emitting sounds within a narrow frequency band. Unlike the other buzzer you need to provide a signal of the appropriate frequency to make this device work.
- Shock Sensor – The shock sensor is an electromechanical device that detects vibration. It is a simple device consisting of a metal tube with a spring inside.
- Small Microphone – The small microphone is nearly identical to the large microphone except that uses a much smaller sensor element.
- Tap Module – The tap module is sometimes referred to as a percussion sensor. Is an electromechanical device that detects when it has been knocked.
Joysticks and switches that take input from people. See more in Arduino 37 Sensors Part 4.
- Heartbeat Sensor – The heartbeat sensor measures your pulse rate by beaming light through your fingertip and measuring the amount of light that passes through.
- Joystick – The joystick is an input device designed to pass the X & Y coordinates of its position to your Arduino.
- Pushbutton – The pushbutton is a very simple input device. This sensor has an integral pull up resistor to simplify its use.
- Rotary Encoder – This device is used a bit like a potentiometer except it continuously rotates. It send its information by a series of digital pulses.
- Touch Sensor – This is a switch that is triggered by the touch of your fingertip. You’ve probably seen similar devices on elevators.
A series of sensors that are either triggered by magnets or that detect magnetic fields. More information in Arduino 37 Sensors Part 5.
- Analog Hall – A Hall Effect sensor is a semiconductor device that can detect a change in a magnetic field.
- Hall Magnetic – This is an advanced Hall Effect sensor that has both an analog and digital output.
- Linear Hall Sensor – This is a sensitive Hall effect sensor with an analog output. It would be useful in creating a compass.
- Mini Reed Switch – This is a tiny magnetic reed switch which is activated when a magnet is held close to it.
- Reed Switch – This is a full size magnetic reed switch. These devices are often used in security systems.
Detectors that trigger when moved into a specific position. Learn more in Arduino 37 Sensors Part 6.
- Ball Switch – This device consists of a tiny metal bead that closes a switch gap when held in a specific position.
- Light Cups – This sensor actually consists of two devices, each with a mercury switch and LED. They can be used to create a “light cup” effect.
- Tilt Switch – This is a mercury switch, used to detect when a device has been moved into a specific position.
Devices that measure the proximity to nearby objects. Detailed information is in Arduino 37 Sensors Part 7.
- Line Tracker – This is an infrared source and sensor assembly used in line tracking applications. You could build a line following robot with this device.
- Obstacle Avoidance – This is another infrared source and sensor assembly used to detect the presence of obstacles. it works using a similar principle as those ultrasonic source-sensor assemblies that are often used in Arduino projects.
Sensors for temperature and humidity. See how you can make use of them in Arduino 37 Sensors Part 8.
- Analog Temperature – The analog temperature device makes use of a thermistor, which is a resistor that changes resistance with temperature.
- Digital Temperature – The digital temperature device also uses a thermistor but outputs both an analog and digital signal. The digital signal indicates that a preset temperature threshold has been crossed.
- Temperature – This temperature device is a semiconductor temperature sensor.
- Temperature & Humidity – This device senses both temperature and humidity and outputs a digital signal.
One final interface, a relay to control external devices. See how to use it in Arduino Sensors Part 9.
- Relay – The relay is an output device. It allows you to control high current appliances with your Arduino
Stay Tuned – There’s More to Come!
So there you have it, all 37 Arduino Sensors. Please join me for the other articles in this series and learn more about each one of these fascinating little devices.
- Light – Arduino 37 Sensors Part 2.
- Sound & Vibration – Arduino 37 Sensors Part 3.
- Human Interaction – Arduino 37 Sensors Part 4.
- Magnetic Fields – Arduino 37 Sensors Part 5.
- Position Sensing – Arduino 37 Sensors Part 6.
- Proximity Detection – Arduino 37 Sensors Part 7.
- Weather – Arduino 37 Sensors Part 8.
- External Control – Arduino 37 Sensors Part 9.