Adaptive Assembly

SearchHole

Primitive Description and Usage

• Description: This primitive provides a force-search mechanism to control the robot to find the hole in peg-in-hole assembly tasks. Specifically, it controls the robot to search along an increasingly dense trajectory within a circular or rectangular area on a surface while maintaining a certain contact force.

• Example Usage: Use this primitive to position the hole before performing the peg-in-hole assembly tasks.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
contactAxis	Contact (force control) direction in TCP coordinate system, which should be along one of TCP’s principal axes [X, Y, Z]	VEC_3d	none	0.0 0.0 1.0 ∈ [0.0 0.0 0.0 … 1.0 1.0 1.0]
contactForce	Contact force when searching on the surface	DOUBLE	N	5 ∈ [2 … 20]
searchAxis	Search direction in TCP coordinate system, which should be perpendicular to the contact axis	VEC_3d	none	1.0 0.0 0.0
searchPattern	Pattern formed by the searching trajectory (spiral or zigzag)	TYPE	none	SPIRAL ∈ [SPIRAL ZIGZAG]
spiralRadius	Searching area radius of spiral search pattern; when payload or contact surface friction/resistance is large, this value might be slightly smaller than its nominal value.	DOUBLE	m	0.015 ∈ [0.001 … 0.015]
zigzagLength	Searching area length of zigzag search pattern along the search axis; when payload or contact surface friction/resistance is large, this value might be slightly smaller than its nominal value.	DOUBLE	m	0.03 ∈ [0.001 … 0.03]
zigzagWidth	Searching area width of zigzag search pattern, which is perpendicular to the search and contact axis; when payload or contact surface friction/resistance is large, this value might be slightly smaller than its nominal value.	DOUBLE	m	0.03 ∈ [0.001 … 0.03]
startDensity	Number of times the geometry pattern will be drawn in the start cycle	INT	none	2 ∈ [1 … 5]
timeFactor	Time factor for how long it takes for TCP to form a pattern. Caution: 1. Small time factor for a large search radius may cause the robot to exceed its capabilities and stop. 2. In Manual mode, this factor is approximately doubled regardless of the speed percentage.	INT	none	2 ∈ [1 … 10]
wiggleRange	Range for TCP to wiggle along the contact axis to find the right angle during searching. Caution: If this parameter is set to a large value, make sure to increase the wigglePeriod, otherwise, the robot may exceed its capabilities.	DOUBLE	deg	0 ∈ [0 … 90]
wigglePeriod	Time period for TCP to wiggle along the contact axis back and forth once. Caution: 1. Setting this value too small will likely cause the robot exceeding its capabilities and stop, especially when the wiggle motion is not along the Z-axis of the robot flange. 2. in manual mode, this factor is approximately doubled regardless of the speed percentage.	DOUBLE	s	0.3 ∈ [0.2 … 30]
enableMaxWrench	Flag to indicate if maximum contact wrench is enabled in each Cartesian direction: X, Y, Z, Rx, Ry, Rz	VEC_6i	none	0 0 0 0 0 0 ∈ [0 0 0 0 0 0 … 1 1 1 1 1 1]
maxContactWrench	Maximum contact wrench allowed for static collision along Fx, Fy, Fz, Mx, My, Mz	VEC_6d	N	150.0 150.0 150.0 40.0 40.0 40.0 ∈ [5.0 5.0 5.0 1.0 1.0 1.0 … 150.0 150.0 150.0 40.0 40.0 40.0]
searchImmed	Start searching immediately without waiting for contact force to reach its set value	BOOL	none	1 ∈ [0 / 1]
searchStiffRatio	Factor of the stiffness during searching motion. Caution: Setting this value too small, the robot may not follow the searching trajectory very well, especially when the surface friction or contact force is very large.	DOUBLE	none	1 ∈ [0.1 … 1]
maxVelForceDir	Maximum movement velocity along force control direction	DOUBLE	m/s	0.1 ∈ [0.005 … 0.5]

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	The termination flag of the primitive. It is set to true if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
searchResisForce	Feedback force during searching motion, which could indicate the collision or resistance.	DOUBLE	N
pushDis	Pushed distance of TCP into the surface, which could signal a successful find.	DOUBLE	m
forceDrop	Dropped value from the set contact force. Caution: this state will not be reliable if input parameter [searchImmed] is set to TRUE.	DOUBLE	N
lostContact	Flag to indicate the loss of contact. This flag will only be switched on when the forces detected on all X, Y, Z, Rx, Ry, Rz axes are smaller than 1N or 1Nm for 1.5 consecutive seconds.	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
pushDistance	>	0.005

CheckPiH

Primitive Description and Usage

• Description: This primitive helps check if a peg is already in a hole. You can specify a contact axis and a search axis perpendicular to the contact axis, and a companion axis will be generated to form a frame. The robot will move toward the +searchAxis, -searchAxis, -companionAxis, +companionAxis. While moving along these axes, if the robot goes over the limit specified by [searchRange], the primitive will terminate and the state parameter [pegIsInHole] will be set to false; if the robot encounters a force greater than [searchForce] along all these directions during the process, the primitive will terminate and [pegIsInHole] will be set to true.

• Example Usage: Use this primitive to check if a peg-in-hole operation is completed.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
contactAxis	Contact (force control) direction in TCP coordinate system, which should be along one of TCP’s principal axes [X, Y, Z]	VEC_3d	none	0.0 0.0 1.0
searchAxis	Search direction in TCP coordinate system, which should be perpendicular to the contact axis	VEC_3d	none	1.0 0.0 0.0
searchRange	Range within which the robot will make forward, backward, left, and right search motions	DOUBLE	m	0.01 ∈ [0.001 … 0.1]
searchForce	Force threshold to detect if the robot can move along the searching direction. Robot will move along the next motion direction when detected force is greater than this value.	DOUBLE	N	3 ∈ [2 … 20]
searchVel	TCP linear velocity for the searching motion	DOUBLE	m/s	0.01 ∈ [0.001 … 0.1]
linearSearchOnly	Flag to indicate if the robot only searches linearly in the direction of +searchAxis and -searchAxis	BOOL	none	0 ∈ [0 / 1]
returnToInitPose	Flag to indicate if the robot would return to initial pose when check is failed	BOOL	none	true ∈ [0 / 1]

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	The termination flag of the primitive. It is set to true if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
pegIsInHole	Flag to indicate if the peg is already in the hole	BOOL	none
checkComplete	Flag to indicate if the peg-in-hole check 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
initTcpPose	Initial TCP pose when the project runs to this primitive	COORD	m-deg

Default Transition Condition

State Parameter	Condition	Value
checkComplete	=	1

InsertComp

Primitive Description and Usage

• Description: This primitive moves the robot in a predefined insertion direction until the total external force reaches a set value. During the insertion process, if there is an external force in directions other than the insertion direction that exceeds the deadband, the robot will stop the insertion motion and adjust its position and orientation in the corresponding direction until the forces in all directions are within the deadband.

• Example Usage: Use this primitive in fine assembly tasks such as gearbox assembly, peg-in-hole assembly, or in machine tending applications like putting a sleeve (a hollow cylinder) on a shaft.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
insertAxis*	Insertion direction in TCP coordinate system	TYPE	none	[X -X Y -Y Z -Z]
compAxis	Force compliance axes in TCP coordinate system. The robot performs compliant motion along the axis whose value is set to 1.	VEC_6i	none	0 0 0 0 0 0 ∈ [0 0 0 0 0 0 … 1 1 1 1 1 1]
maxContactForce	Maximum contact force. The primitive will be terminated when external force exceeds this limit.	DOUBLE	N	5 ∈ [1 … 120]
deadbandScale	Deadband scale of applied alignment wrench. The robot only performs compliant motion when the external wrench is higher than this deadband. 0 means no deadband.	DOUBLE	none	50 ∈ [10 … 100]
insertVel	TCP Linear velocity in insertion direction	DOUBLE	m/s	0.01 ∈ [0.001 … 0.1]
compVelScale	Velocity scale of compliant motion. Higher velocity scale results in faster but less stable compliant motion.	DOUBLE	none	20 ∈ [10 … 100]

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

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	The termination flag of the primitive. It is set to true if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
insertDis	Robot moving distance in the insertion direction	DOUBLE	m
isMoving	Flag to indicate if robot is still moving	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
isMoving	=	0

Mate

Primitive Description and Usage

• Description: This primitive moves the robot back and forth in one direction while applying a certain force in a specific direction until mating is complete. The mating success rate can be improved by adding mating motion in another direction.

• Example Usage: Use this primitive for parts mating in assembly tasks.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
contactAxis	Contact (force control) direction in TCP coordinate system, which should be along one of TCP’s principal axes [X, Y, Z]	VEC_3i	none	0 0 1 ∈ [-1 -1 -1 … 1 1 1]
contactForce	Target force along the contact axis	DOUBLE	N	15 ∈ [5 … 50]
matingAxis	An axis in TCP coordinate system representing the sliding or rotating direction during mating, which should not be the same as contact axis	VEC_6i	none	0 1 0 0 0 0 ∈ [-1 -1 -1 -1 -1 -1 … 1 1 1 1 1 1]
slideMatingRange	Sliding mating motion range	DOUBLE	m	0.1 ∈ [0.001 … 0.35]
slideMatingVel	TCP linear velocity of sliding mating motion	DOUBLE	m/s	0.1 ∈ [0.001 … 0.5]
slideMatingAcc	TCP linear acceleration of sliding mating motion	DOUBLE	m/s^2	1.0 ∈ [0.1 … 2.5]
rotateMatingRange	Rotating mating motion range	DOUBLE	deg	10 ∈ [1 … 60]
rotateMatingVel	TCP angular velocity of rotating mating motion	DOUBLE	deg/s	10 ∈ [1.0 … 60.0]
rotateMatingAcc	TCP angular acceleration of rotating mating motion	DOUBLE	deg/s^2	180 ∈ [5 … 500]
matingTimes	Total number of mating times. The primitive will be terminated when the specified number of times of mating motion is reached. Caution: If set to 0, the robot performs ONLY forward motion once.	INT	none	1 ∈ [0 … 1000]
maxContactDis	Maximum moving distance along contact axis. The primitive will be terminated when the moving distance exceeds this value.	DOUBLE	m	0.05 ∈ [0.005 … 0.5]
safetyForce	Safety force limit during mating. The primitive will be terminated when the feedback force exceeds this value.	DOUBLE	N	50.0 ∈ [20 … 80]
addMatingAxis	An additional axis in TCP coordinate system representing the sliding or rotating direction during mating, which should not be the same as contact axis or mating axis. The additional mating motion along this axis will be superimposed on the mating motion.	VEC_6i	none	0 0 0 0 0 0 ∈ [-1 -1 -1 -1 -1 -1 … 1 1 1 1 1 1]
addSlideMatingRange	Additional sliding mating motion range	DOUBLE	m	0.05 ∈ [0.001 … 0.1]
addSlideMatingVel	TCP linear velocity of additional sliding mating motion	DOUBLE	m/s	0.1 ∈ [0.001 … 0.5]
addSlideMatingAcc	TCP linear acceleration of additional sliding mating motion	DOUBLE	m/s^2	1.0 ∈ [0.1 … 2.5]
addRotateMatingRange	Additional rotating mating motion range	DOUBLE	deg	10 ∈ [1 … 60]
addRotateMatingVel	TCP angular velocity of additional rotating mating motion	DOUBLE	deg/s	10 ∈ [1.0 … 60.0]
addRotateMatingAcc	TCP angular acceleration of additional rotating mating motion	DOUBLE	deg/s^2	180 ∈ [5 … 500]
maxVelForceDir	Maximum movement velocity along force control direction. It constrains the robot’s speed in cases where the robot suddenly loses contact with the environment. Note that if its value is set too small, the robot’s force control performance may degrade.	DOUBLE	m/s	0.5 ∈ [0.002 … 0.5]

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	The termination flag of the primitive. It is set to true if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
matingFinish	Flag to indicate if the mating process is finished	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
matingFinished	=	1

FastenScrew

Primitive Description and Usage

• Description: This primitive is applicable to screw fastening tasks. During the fastening process, the robot maintains contact with objects along the insertion direction while performing compliant motion in other directions.

• Example Usage: Use this primitive to fasten the screws in assembly applications.

Primitive Input Parameters

Input Parameter	Description	Type	Unit	Default Value & Range
insertDir	Screw insertion direction in TCP coordinate system	TYPE	none	Z ∈ [X -X Y -Y Z -Z]
maxInsertVel	Maximum screw insertion velocity into the screw hole	DOUBLE	m/s	0.01 ∈ [0.001 … 0.05]
insertForce	Screw insertion force during fastening process	DOUBLE	N	20 ∈ [10 … 50]
stiffScale	Robot stiffness scale while fastening the screw. Lower scale applies higher motion compliance.	DOUBLE	none	0.5 ∈ [0.1 … 1]
diScrewInHole	Digital input port which receives the signal from screw gun, indicating that screw has been tightened a bit into the screw hole.	TYPE	none	NONE ∈ [NONE, gpioIn0 … gpioIn15, modbusIn0 … modbusIn15]
diFastenFinish	Digital input port which receives the signal from screw gun, indicating that screw has been totally tightened.	TYPE	none	NONE ∈ [NONE, gpioIn0 … gpioIn15, modbusIn0 … modbusIn15]
diScrewJam	Digital input port which receives the signal from screw gun, indicating that screw has been jammed.	TYPE	none	NONE ∈ [NONE, gpioIn0 … gpioIn15, modbusIn0 … modbusIn15]

Primitive State Parameters

State Parameter	Description	Type	Unit
terminated	The termination flag of the primitive. It is set to true if the primitive is terminated.	BOOL	none
timePeriod	The time spent on running the current primitive.	DOUBLE	s
insertDis	Screw insertion distance into the screw hole	DOUBLE	m
insertVel	Screw insertion velocity into the screw hole	DOUBLE	m/s
fastenState	Screw fastening state: 0 means default state; 1 means screw has been tightened a bit into the screw hole; 2 means screw has been totally tightened; -1 means screw has been jammed.	INT	none
reachedHole	Flag to indicate screw has reached full contact with screw hole	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
fastenState	=	2