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signal following robot? Answered

Hi community, i would really make a robot that follows a signal maybe wifi signal
the idea is to keep a small chip (transmitter) in my pocket and the receiver would be installed on the robot body or the reverse, so the robot would follow the signal,  and im really thinking to use a tank body ( not wheels) with two  motors that will drive body  just as a tank or Caterpillar digger concept

So can the community experts help me how can  i realize my dream, and tell me what could be the parts and how it would work??

Thank you so much community you have been always helpful ! 



Best Answer 4 years ago

Tough question. There are multiple ways of approach. each working differently. here are a few i can think of.

1) IR-BEACON: a simple IR lightsource keeps sending out a signal. 2 receivers on the robot with a different view would keep looking for this signal. if the beacon goes into view of either receiver the robot then knows that the beacon is to the left or right and start its pursuit. I used this kind of tracking to make a robot play football once.

2) Sonar-clicker: 2 sonar sensors on the robot and a sonar transmitter on the user. The transmitter sends out a click and the sensors will carefully listen to this click. By determining which one would hear the click first the robot can figure out which is is closer. its a bit more sophisticated than the IR-Beacon. the video mpilch linked is a good example of this kind.

3) Radio-Direction-Finder: A not so easy to implement idea, but interesting to try. The user would carry a radio transmitter. The robot would have a Directional Receiver or 2 listening for the broadcast. I think that one could make a directional receiver out of a simple Cheap RF-transmitter/receiver pair by isolating the receiver from all directions by a metal casing except for the direction it is to listen towards (A radio signal cannot pass trough solid metal). Ive seen a project where someone created a Directional Wi-Fi tracker by placing a WiFi module in a servo-rotated metal tube created out of tin-cans! The big problem is that you would need to figure out a way to measure the signal strength...like how often it receives the broadcasted signal intact. It is tricky, but it would make a epic Instructable if somebody does this.

I had a friend ask a similar question of me the other day. I'm sure you could do something with GPS modules as they can have a pretty decent location resolution. You and your bot would each have one and be connected through a pair of bluetooth modules as well, and then the bot would calculate speed, direction and distance to catch up.

Google for "RFID following robot".

Here is one way of doing it.