Main methods¶
Main methods to use the tracker are startTracker() / stopTracker().
Overview | ALRedBallTracker API | ALFaceTracker API | Trackers Sample
The Tracker modules allow you to make NAO track targets (a red ball or a face).
The main goal of these modules is to establish a bridge between target detection and motion in order to make NAO keep in view the target in the middle of the camera.
A - Starts the tracker by Subscribing to Event TargetDetected from ALTargetDetection module (ALRedBallTrackerProxy::startTracker() or ALFaceTrackerProxy::startTracker()).
B - Waits Event TargetDetected from ALTargetDetection module.
C - When target is detected, sends information to motion of the position of the new target (ALMotionProxy::updateTrackerTarget()).
D - Stops the tracker by Unsubscribing to Event TargetDetected from ALTargetDetection module (ALRedBallTrackerProxy::stopTracker(), ALFaceTrackerProxy::stopTracker()).
Limitations
This is done assuming an average target size, so it might not be very accurate.
Choose the kind of motion tracking using the following api: (ALRedBallTrackerProxy::setWholeBodyOn() or ALFaceTrackerProxy::setWholeBodyOn()).
Main methods to use the tracker are startTracker() / stopTracker().
Here are some possible applications (from the simplest to the more ambitious ones) that can be built from NAO’s ability to track a target.
Case 1: Tracking the red ball using the head: Red Ball Tracker Sample
Case 2: Tracking the red ball using the whole body motion: Tracking a red ball with NAO’s whole body
Case 3: Walk toward a person: Tracking a face using the Walk Tracker box