High-Performance Vision Guidance

VSTeach

Primitive Description and Usage

• Description: This primitive collects samples of image feature data or object poses from the visual system multiple times and outputs their average values.

• Example Usage: Use this primitive to record the features of the target image or the poses of the target object after moving the robot to the target position. You can record the values of the output parameters of this primitive into variables and then use them in the primitives [HPImageBasedVS] or [HPPoseBasedVS].

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
objName*	Object name used by visual servoing	OBJNAME	none
objIndex	Object index used by visual servoing	INT	none	0 ∈ [0 … 1]
collectTimes	Number of times of collecting image feature samples	INT	none	30 ∈ [10 … 200]

*Parameters marked with an asterisk must be assigned a value prior to executing the primitive.

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	Flag to indicate whether the primitive is terminated. It is set to TRUE if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
teachFinished	Flag to indicate whether the teaching data collection is complete	BOOL	none

Primitive Output Parameters

Output Parameter	Description	Type	Unit
tcpPoseOut	The TCP pose when the primitive is terminated. It is represented in the world coordinate system.	COORD	m-deg
taughtFeaturePts2D	Positions of multiple taught feature points in the 2D camera coordinate system. Its value can be used as the input parameter [targetFeaturePts] for the primitive [HPImageBasedVS].	ARRAY_VEC_2d	none
taughtAlignPts2D	Positions of the feature points of the aligned object in the 2D camera coordinate system during teaching. Its value can be used as the input parameter [alignObjPts] for the primitive [HPImageBasedVS].	ARRAY_VEC_2d	none
taughtFeaturePtsNoise	Noise of the taught 2D feature points. Its value can be used as the input parameter [visualDetectNoise] for the primitive [HPImageBasedVS].	ARRAY_VEC_2d	none
taughtFeaturePts3D	Positions of multiple taught feature points in the 3D camera coordinate system. Its value can be used as the input parameter [targetFeaturePts] for the primitive [HPPoseBasedVS].	ARRAY_VEC_3d	m
taughtAlignPts3D	Positions of the feature points of the aligned object in the 3D camera coordinate system during teaching. Its value can be used as the input parameter [alignObjPts] for the primitive [HPPoseBasedVS].	ARRAY_VEC_3d	m
taughtObjPose	Pose of the target object taught in the 3D camera coordinate system. Its value can be used as the input parameter [targetObjPose] for the primitive [HPPoseBasedVS].	POSE	mm-deg
taughtAlignPose	Pose of the aligned object in the 3D camera coordinate system during teaching. Its value can be used as the input parameter [alignObjPose] for the primitive [HPPoseBasedVS].	POSE	mm-deg

Default Transition Condition

State Parameter	Condition	Value
teachFinished	=	1

HPImageBasedVS

Primitive Description and Usage

• Description: This primitive uses Image-Based Visual Servoing (IBVS), leveraging real-time visual feedback to continuously control the robot to track objects with random and unpredictable positions, achieving high-precision, high-responsiveness, and quasi-static tracking. During this process, the robot moves along the visual servoing axes to align the feature points on the target object with the target feature points.

• Example Usage: Use this primitive to control the robot to locate an object whose position is uncertain or changing on the plane. This primitive can also be used to align two objects, such as aligning an FPC cable with a socket.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
objName*	Object name used by visual servoing	OBJNAME	none
objIndex	Object index used by visual servoing	INT	none	0 ∈ [0 … 1]
targetFeaturePts*	Position of the target feature points in the 2D camera coordinate system. Each point is represented by two pixel values (X, Y).	ARRAY_VEC_2d	none
targetDepth*	Depth of target feature points in the camera coordinate system	ARRAY_DOUBLE	m	[0.01 … 1.2]
vsAxis	Axes that are allowed to move in the camera coordinate system	VEC_6i	none	1 1 1 0 0 0 ∈ [0 0 0 0 0 0 … 1 1 1 0 0 0]
velScale	Velocity scale of visual servoing. Caution: Setting this value too large may cause robot vibration.	DOUBLE	none	10 ∈ [1.0 … 100.0]
maxVel	Maximum linear velocity of robot movement	DOUBLE	m/s	0.05 ∈ [0.001 … 0.5]
imageConvToler	Tolerance for determining whether the image has converged. When the error between the captured image features and the target features is within the tolerance, it will be determined that convergence has occurred.	DOUBLE	none	5.0 ∈ [1 … 50]
targetConvTimes	Number of consecutive times the target simultaneously meets the image convergence tolerances. When the number of consecutive convergences reaches this set value, the parameter [objAligned] will be set to TRUE; 0 indicates that [objAligned] will never be TRUE.	INT	none	4 ∈ [0 … 20]
timeoutTime	Maximum time interval allowed for receiving data. A fault will be triggered if the robot fails to receive visual feedback data within this time interval.	DOUBLE	s	3 ∈ [0.1 … 10]
enableObjAlign	Flag to enable the object alignment function. This function can be used to align the feature points of two objects.	BOOL	none	0 ∈ [0 / 1]
alignObjPts	Position of feature points of aligned object in the 2D camera coordinate system. Each point is represented by two pixel values (X, Y). The aligned object is in the robot hand and is moved by the robot.	ARRAY_VEC_2d	none
optVelScale	Increase the velocity scale of visual servoing in the Z and Rz directions. It can help optimize the robot’s Cartesian motion trajectory.	VEC_2d	none	0 0 ∈ [0 0 … 100 0]
visualDetectNoise	Noise of the visual detection result of each feature point	ARRAY_VEC_2d	none	[0 0 … 20 20]

*Parameters marked with an asterisk must be assigned a value prior to executing the primitive.

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	Flag to indicate whether the primitive is terminated. It is set to TRUE if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
objAligned	Flag to indicate whether visual servoing has successfully aligned the target object	BOOL	none

Primitive Output Parameters

Output Parameter	Description	Type	Unit
tcpPoseOut	The TCP pose when the primitive is terminated. It is represented in the world coordinate system.	COORD	m-deg

Default Transition Condition

State Parameter	Condition	Value
reachedTarget	=	1