Introduction We’re going to talk about 5 project ideas you can do for your bike with an Arduino card. The idea is to have projects that are simple to do and that can improve the use of your bike on a daily basis. Today we use more and more electronic objects in our bike without even realizing it. Whether it’s lights, speedometers or even electric bikes.We will see different projects to bring more comfort or more features to your bike. Bike lighting Difficulty How about a light that turns on according to the darkness? With Arduino it is possible! You can use a photoresistor that will capture the outside light and the Arduino board will adapt the intensity of the leds according to the darkness.Then you just need to connect a battery to make the project autonomous. The advantage of this project is that it is very simple to set up.The negative point of this project is that the Arduino board consumes a lot of energy compared to the task it has to do. This can be annoying if the board is on battery. So you can think about replacing the arduino board by a microcontroller chip less powerful and less energy consuming. Speedometer Difficulty How about a speedometer that tells you how fast you’re going, how many miles you’ve traveled, or how close you are to your goal in miles. This idea may seem a bit useless at first because speedometers are available on the market.However, the advantage of the Arduino board is that you can make a project that corresponds exactly to what you want, with the examples mentioned above. To make a speedometer, you will need a hall effect sensor and a magnet to detect the passage of the wheel. A hall effect sensor detects the variation of a magnetic field. It can be placed on the fork of the bike and the magnet on one of the spokes of the bike. When the magnet is approaching the sensor, this one is going to detect the variation of the field and thus to know that one made a turn of wheel.You will also need an LCD screen to read the speedometer information. Direction indicator on the backpack Difficulty Are you interested in having a bag that tells the cars behind you where you are going? This kind of bag is very useful for more safety. The other road users can know your next intentions and anticipate them.For this you need to use pads or led strips that you will stick behind a backpack. You can then put the Arduino board in your bag with a battery to make the project autonomous. You can use an infrared remote control with a receiver to control the different signals. The remote control can be placed on the handlebar.You will then have to program different signals on the led strip: a right or left arrow. An arrow straight ahead to indicate that we continue straight ahead. Connected padlocks Difficulty How about a lock that locks and unlocks with your fingerprint?With Arduino it’s possible! For this you will need a fingerprint sensor. You can connect the fingerprint sensor to the Arduino board so that it can check if the fingerprint matches the one registered. Once the match is done, the arduino board will open the lock. An Arduino board consumes a lot of energy. It is therefore necessary that it is turned off when not in use to avoid draining the battery.You can use a switch between the battery and the Arduino board. Simplification of the project! One way to simplify the project is to use an RFID sensor instead of the fingerprint sensor. This allows you to simplify the project while still using the lock securely.You will then have a badge attached to your keys to unlock your padlock. Gps Module Difficulty What about a GPS tag that tells you where your bike is in real time?This can be very useful if you are afraid of having your bike stolen for example. For this you will need a GPS module connected to an Arduino board. Once the position of the bike is retrieved by the module, it will be necessary to transmit it to you. For that you can use a GSM module with a SIM card to send the GPS positions by sms to your phone. This project can be powered by battery. We advise you to turn off the GPS and GSM module when they are not used. We also advise you to retrieve the GPS position and to send an SMS once every 2 minutes in order not to wear out the battery. Bonus : Convert your bike to an electric one Difficulty One of the projects that may be the most fashionable at the moment is how to turn your bike into an electric one. For this nothing very complicated, you will need a motor that you will drive with your Arduino board. For the choice of the motor, you can look at our stepper motor course. This motor must have enough torque to support the load of the bike plus you. You will then need a battery to power the motor. For this there are battery packs made directly for bikes. Then to connect the battery to the motor you can use an Arduino board. You can put a potentiometer on your handlebar to adjust the power of the motor. Then with a transistor between the battery, arduino board and motor you can manage the power given by the battery on the motor.You can then have a small LCD screen that indicates the number of kilometers traveled since the last charge, the number of kilometers you can still do. To know this you can make a test by using the bike until it has no more battery and you know like that how many kilometers the battery holds.