I will show you how to build a bike speedometer. It shows your speed,
the average speed,the temperature, the trip time and the total distance. You can change it using the button. Additionally, the speed is shown on a tachometer. I built it because I like building new things, I have not found anything like this on the internet so I want to show you how to build a good speedometer as the one on my bike is not as cool as I want :) . So let's get started.

Step 1: Parts:

This is a list of parts that you will need. They cost me about $ 40 but I bought them in Poland.


-bike with reed switch

-LCD display 16x2



-thermometer DS18B20

-resistor 1.2k Ω , 4.7k Ω



-potentiometer 10 kΩ

-9V battery



-tools (drill, soldering, knife, tape)


<p>This is a speedometer ,not a tachometer.</p>
<p>Which arduino board you have used?</p>
<p>i have run the code, but it counts by it self and the speed is 63 as a stable speed. It should give 0.00 . Any solution for that?</p><p>and thank you for the ide</p>
<p>I have the same problem. </p>
<p>Looks really cool! I can put this on my To-Do list (after I learn arduino :( ...)</p>
<p>Thanks! Good luck with arduino </p>
<p>Could you tell us more about Reed switches and How to connect Reed switch to wheels..?</p>
<p>is there anychance that the sensor would be a steppermotor connected to the wheel ?</p>
<p>If you were to connect a regular motor to the wheel, you could measure its voltage and get an accurate reading of your speed, you could also use that voltage to run your system and forgo batteries altogether!</p>
<p>I've never done anything with steppermotors so I do not know. Now I'm going on holiday so I can't check it but when I get back I'll try.</p>
<p>Cool project!</p><p>You can save a wire on the DS18B20 by running it in parasite-power-mode. It's supported by the PJRC-library.</p><p>Also, i don't know how much time you get out of the 9V battery, but i cannot be very much. 40% of the energy of the 9V battery is lost as heat in the voltage regulator on the Arduino, and there isn't much more than 600 mAh in one of those, so it will run down very fast. You will get much longer runtime with a battery holder for 3 AA-cells, and connecting that to the 5V-rail. It should be plenty enough to run all your stuff nicely. If not, use 5 AA-cells, and wire it to the VIN-terminal. Then you will have 2000-2500 mAh capacity :D</p>
<p>Thank you.</p><p>I know about the 9V battery, about temperature sensor too. I plan to do a second version which will have a more function and other power will be much smaller size.</p>
<p>what are you using for the sensor</p>
<p>I use reed switch.</p>
Nice idea :)
<p>Thank you :)</p>

About This Instructable




Bio: Hi. My name is Nikodem. I live in Poland, I'm 16 years old. I like to program and invent new things. In the future ... More »
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