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I have a dream to build robotic lawn mower that uses a positioning system, so that can cut grass once and effective. Building the robotic lawn mower is not a problem, but the navigation system is, so I came up with an ultrasound idea to locate the lawn mower on a field.
Basically the lawn mower will have mic mounted on it and will be listening for a signal from the speakers. There will be four ultrasound speakers in each corner emitting sound. At a start lawn mower will send by RF signal to first speaker to send sound and then will measure time and calculate distance. Then will do this process with second speaker and so on. When it will come to the end it will take all distance and calculate where exactly is it on field.
Now I have some questions will this system work outside and in greater distances like 100 meters X 100 meters? Which ultrasound speaker/mic is best for this job? Is there a better way to control position of lawn mower? Will this system ever work?