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"Multi Foraging" means the robot can sense several different classes of objects to collect, along with different bins in which to to deposit them. A SimpleN150 robot has sonar range finders, bumper switches, and odometry and steering, translation and turret motors. These capabilities are extended on a MultiForageN150 through the addition of color vision and a gripper.
Vision sensing
Vision hardware provides six "channels" that each track a different
type of object. Each call to one of the vision routines requires a reference
to which channel is being accessed.
Bins and objects to collect are sensed by the same vision hardware.
Frames of reference
We use a standard cartesian coordinate system in
meters and radians. Pretend you are looking down
on the robot: +x
goes out to your right (East), +y goes up (North).
When the robot is initialized, it is facing the +x direction.
Headings are given in radians, with East=0, North=PI/2 and so on CCW
around to 2*PI.
Some methods return "egocentric" vectors.
An egocentric vector is given relative to the center of
the robot in the same heading reference frame as global coordinates.
An object one meter east of the robot is at (1,0) egocentrically.
Implementations
This class is extended by a simulation class (MultiForageN150Sim)
and a physical robot class (MultiForageN150Hard). The subclasses
handle details of interaction with the real or simulated
world.
Timestamps
Many of the sensor and motor command
methods (e.g. get* and set*) require a timestamp as a parameter.
This is to help reduce the amount of I/O to the physical robot.
If the timestamp is less than or equal to the value sent on the
last call to one of these methods, old data is returned.
If the timestamp is -1 or greater than the last timestamp, the
robot is queried, and new data is returned. The idea is
that during each control cycle the higher level software will
increment the timestamp and use it for all calls to these methods.
Copyright (c)1997, 1998 Tucker Balch
public static final double VISION_RANGE
public static final int VISION_FOV_DEG
public static final double VISION_FOV_RAD
public static final double GRIPPER_CAPTURE_RADIUS
public static final double GRIPPER_POSITION
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