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MONITORING THE REVOLUTIONS

A Pedal Cadence Counter
by Matt Meerian

Start ý The Hardware ý Microcontroller Software ý Desktop Software ý Placement ý Happy Trails ý Sources and PDF

Almost everyone has the goal of becoming or staying physically fit. There are many ways to accomplish this goal, but the best way is to find an exercise that you enjoy. If you enjoy the activity, you are more likely to exercise on a daily basis over a period of many years. But, sometimes itýs difficult to determine how much of a workout you are getting. With this design, I merged two of my hobbies, electronic gadgetry and mountain biking.

There are many types of speedometer/odometer gauges for bicycles. Most displays give you instant feedback on your speed and mileage. But, cadence is a more accurate barometer for gauging a workout.

Good cadence on a bicycle is a high number of pedal revolutions against low resistance. Experts recommend 60 to 90 pedal revolutions per minute (rpm) for an optimum workout. High rpm and low torque give a better workout and increased endurance for the rider than a number of low revolutions and high torque.

This project allowed me to use two vastly different programming languages. The microcontroller is programmed in assembly language, and the desktop computer is programmed in Visual Basic.

As with most projects these days, the hardware is easy and straightforward and the software is the time-consuming, complicated part of the project. Letýs start with the easy, straightforward part and work our way up.

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