Electronic – arduino – How long does ultrasonic rangefinder last

arduino

I've built a parking sensor in my garage that uses the HC-SR04 ultrasonic rangefinder and an arduino to measure how far the car is from the back wall.

The one thing that I'm worried about is if the sensor will continue to work for a long time. When it senses an object, it senses distance 10 times per second and once there's a period of inactivity, I scale it down so that it senses distance once per second. So it will be sensing once per second pretty much all the time, which is like 86000 per day, or 31 million times per year. Anyone know if these sensors go bad over time or if they're rated for a certain number of senses?

Thanks for any advice!

Best Answer

First off, sensing the distance once per second may be too slow even for a parking application. Consider that 2 mph is equivalent to over 2.9 feet per second. Almost 3 feet is a large distance in a garage. In any event, I don't think you have to worry about the reliability of the sensor. Quartz watches run continuously for years without any problems. If the watch is analog, that means the parts associated with moving the second hand are operating once per second 24 hours per day or 31 million times per year as you have pointed out. Garage door openers have object sensors to prevent accidents that are also on continuously and last for years.