> -----Original Message-----
> From: 沉渔涧 [mailto:iamnortheastern@...]
> Sent: Monday, April 18, 2011 9:47 PM
> To: playerstage-users@...
> Subject: [Playerstage-users] how to guide the robot in stage?
> following is the world in stage environment, the robot, pink crab
> stands at the lower left corner of the world, facing upwards, as
> usually i defined the crab's facing direction as positive x axis, and
> right hand as positive y axis. On the other hand, the object, the pink
> flower stands at the right upper corner of the world. i need the robot
> to move to the flower, what kind of sensors should use to locate the
> relative position regarding the crab ?
> and furthermore, what if i want the robot to recognize the whole world,
> meanly, it knows the world coordinate system, and given this, i can
> directly give the robot the order, goto coordinate (X,Y) - in world
> coordinate system not the robot's regional coordiante system.
You can use a few of the sensors available in Stage. The camera sensor may be easiest, as there is probably nothing else with any color in the environment (though I don't think there is a Player interface for Stage's camera model yet.) You can also try to use the ranger sensor and look for a small object, or you can use the fiducial sensor.
If you want the robot to know where it is globally in Stage, you can go about it one of two ways. The first way is to attempt to localize yourself to a map. You can use the same map file that Stage is using to build the world, or you can attempt to build a map of your environment as you go. Player drivers like amcl and mbicp may help you with that. The second, easier way is to just set Stage to report your global coordinates to your robot. You can do this in your world file by changing the localization type to "gps", or by subscribing to Stage's simulation interface and asking Stage where your robot is in the world.
All of this can be done in either a Player client or a Stage controller.