user27393: Newbe question - I'm thinking of creating a simple robot that heads to a signal source.
Ie, when you press a button on some remote control - the robot will head towards its source.
What would be the best choice of signal? A strength of a wifi, sound?
AD

user27157: IR sensor in combination with an ultrasonic distance sensor would work great.
You can mimic a radar with an IR sensor so that it can detect from where the IR source from your remote is comming from. Then from there, process the angles and make you robot go towards it.
The ultrasonic distance sensor can be used a "fail" prevention system. In the sense that if it detects an object in front of the robot, it will stop, go around it and then continue towards the target

user4143: I like @Canadiancyborg's IR solution, but the same theory can be applied to any other emitter, and RF emitters may be preferable to an IR emitter since IR light can be blocked by intermediate objects. Also an omnidirectional RF transmitter is easier to arrange than an omnidirectional IR transmitter.
The basic theory is that you need to work out which direction a signal is coming from. In order to do that you need to "look around you" and find at which angle the signal is strongest.
A highly directional receiver (parabolic dish, IR receiver with lens, etc) will allow you to sense the signal strongest when the receiver is pointing directly at the source. By then rotating the receiver (either on its own independent rotational system, such as a servo motor, or by rotating the entire robot using the wheels) you can "lock on" to the direction where the signal is strongest and drive towards it.

27393: <p>Newbe question - I'm thinking of creating a simple robot that heads to a signal source.</p>

<p>Ie, when you press a button on some remote control - the robot will head towards its source.</p>

<p>What would be the best choice of signal? A strength of a wifi, sound?</p>

<p>AD</p>
 27157: <p>IR sensor in combination with an ultrasonic distance sensor would work great.</p>

<p>You can mimic a radar with an IR sensor so that it can detect from where the IR source from your remote is comming from. Then from there, process the angles and make you robot go towards it.</p>

<p>The ultrasonic distance sensor can be used a "fail" prevention system. In the sense that if it detects an object in front of the robot, it will stop, go around it and then continue towards the target</p>
 4143: <p>I like @Canadiancyborg's IR solution, but the same theory can be applied to any other emitter, and RF emitters may be preferable to an IR emitter since IR light can be blocked by intermediate objects. Also an omnidirectional RF transmitter is easier to arrange than an omnidirectional IR transmitter.</p>

<p>The basic theory is that you need to work out which direction a signal is coming from. In order to do that you need to "look around you" and find at which angle the signal is strongest.</p>

<p>A highly directional receiver (parabolic dish, IR receiver with lens, etc) will allow you to sense the signal strongest when the receiver is pointing directly at the source. By then rotating the receiver (either on its own independent rotational system, such as a servo motor, or by rotating the entire robot using the wheels) you can "lock on" to the direction where the signal is strongest and drive towards it.</p>
