Distance Sensing: How Far Is It?
What type of proximity sensor is best suited to your next project? We've put together a Proximity Sensor Comparison Guide to help you choose the right tool for the job!
If you have a SparkFun Inventor's Kit and have worked your way through all of the experiments, then you've already worked with a proximity sensor. But what if you're ready to move on, and are looking to do more than make sure your cool little robot can keep from running into the wall? What type of sensor is going to work best? This week we've put together a handy comparison guide to help you navigate through the various options you have when it comes to distance sensing. We'll let you compare range, current draw, resolution, update rate, accuracy and of course, price.
So whether you're making a simple collision avoidance robot, or trying to improve the Automated Rendezvous and Docking (AR&D) system of your next spacecraft, knowing which distance sensor to use will have you well on your way to the successful completion of your project.
What are you building with your proximity sensors? Tell us in the comments below, or let us know what you'd like to see built with distance sensors.
Another use for distance/proximity sensors is trip wire applications. While not as simple to use as a PIR sensor, the sensed area is much more focused. Don't even need to do the calculations to get an actual distance, just watch the signal to see if it changes suddenly. I used it in a past project to turn on a hallway lamp when the front door opens. (The closest power outlet was at the opposite end of the hallway from the door, and it was a rented apartment so I wasn't about to wire in a new outlet.)
Perfect for trigger applications like turning on lights, making noises, or setting off confetti/glitter claymores. ;-)
Rob, I think we saw you before Shawn left, so you can't claim a Dr. Who-like transition! ;-)
LOL...does that make us collectively a single Time Lord? :D
Um... yes!
To be Time Lords you need scarves and sonic screwdrivers... maybe you could stick to being Lords of Grace Hopper's nanoseconds?
Glad you aren't completely gone, Shawn!
Those IR sensors don't measure reflection, they use triangulation to determine distance. So, they are not significantly affected by the color of the object. http://www.sharp-world.com/products/device/lineup/data/pdf/datasheet/gp2y0a21yk_e.pdf
In order for the triangulation to happen, there has to be some amount of reflection (illumination) of the target surface. If the target surface is able to absorb more of the IR light than reflect (or if the surface reflects too much light away from the sensor) then the sensor will never see the IR light and can't get a reading. Thus IR absorbing materials and highly polished surfaces at an angle to the sensor won't get good readings.