Local Positioning System(LPS), similar to Global positioning system(GPS) helps us to locate ourselves or a bot in a small area like offices, shops, etc. This is not often possible with GPS because the low-energy waves used for the GPS system often does not penetrate into multistoreyed buildings. As an alternative, LPS can be used. It is an area of brisk research. Here, I plan to build a simple bot which could move through a hypothetical path marked by LPS coordinates. Currently I think of ultrasonics for range detection
Method of RangingEdit
Ultrasonic waves travel almost Onethrid of a Kilomemter per second(This is variable according to atmospheric conditions, of course!). So for one Kilometer, it would take about 3 seconds. So for one meter this would be about 3x10-4 and for one centimeter, this is about 3x10-6. This difference is easily countable using a Microcontroller(whose clock is usually in the order of Mhz). So by counting this time lag, the distance from a single reference is calculated. We put in more than 3 reference points, and the position of the bot is easily calculated!
- Ultrasonics Generation and Detection
- A reliable system for incorporating more than one ultrasonics signal
- Deciding what is the ultrasonic transmitter and what is the reciever(ie the Bot or the Reference)
- What should be the syncing mechanism
- Can information be encoded in the signalls sent