vcServoController

vcServoController is a controller for driving independent joints. The controller itself only supports forward kinematics and cannot be used in robots rather with them. For example, a servo controller can be used for external axis systems, grippers, fixtures, weld guns, and other simple mechanical structures.

Inherits: vcBehaviour

Properties

Name	Type	Access	Description
FlangeNode	vcNode	RW	Defines the flange node of servo, for example the mount plate or carriage for other kinematic structures.
HeartbeatTime	Real	RW	If UseHeartbeat is set to True, defines the interval or pulse for updating joints.
JointCount	Integer	R	Gets the number of joints in servo.
Joints	List of vcJoint	R	Gets a list of all joints referenced by servo.
RootNode	vcNode	RW	Defines the root node of servo, thereby the fixed base of kinematic structure.
Speed	Real	RW	Defines joint speed as a percentage of maximum speed for driving joints in range 0 to 100.
UseHeartbeat	Boolean	RW	Turns on/off the use of a heartbeat or pulse to drive and update joints.

Methods

Name	Return Type	Parameters	Description
calcMotionTime	Real	None	Returns the calculated motion time of servo using current joint values and listed targets.
createJoint	vcJoint	None	Adds a new joint in servo. (Deprecated)
deleteJoint	None	vcJoint joint or Integer joint_index	Removes a given joint or one at a given index from servo. (Deprecated)
findJoint	vcJoint	String joint_name	Returns the first joint matching a given name in servo; otherwise returns None.
getJoint	vcJoint	Integer joint_index	Returns a joint at a given index in servo.
getJointTarget	Real	Integer joint_index	Returns the target value of a joint at a given index in servo.
getJointValue	Real	Integer joint_index	Returns the current value of a joint at a given index in servo.
move	Real	[Real joint_0, ... Real joint_n]	Drives all joints in servo to target values, and then returns the actual motion time. Target values for each joint in servo can be given as separate, optional arguments.
moveImmediate	None	[Real joint_0, ... Real joint_n]	Drives all joints in servo to target values in zero simulation time. Target values for each joint in servo can be given as separate, optional arguments.
moveJoint	Real	Integer joint_index, Real joint_value	Moves a joint at a given index in servo to a given value, and then returns the actual motion time.
setJointTarget	None	Integer joint_index, Real joint_value	Sets the target value of a joint at a given index in servo to a given value.
setMotionTime	None	Real time	Forces the servo to execute joint movements at a given motion time.

Events

Name	Parameters	Description
OnHeartbeat	vcServoController servo, Enumeration event_type	Triggered when a pulse or heartbeat is generated by servo. See Controller Constants for more information. Note: This event handler can be used by a vcRobotController object executing a vcRslProcessStatement object in robot program.

Examples

Example. Create joint and assign it to servo

from vcScript import *   comp = getComponent() node = comp.findNode("Link_1") node.JointType = VC_JOINTTYPE_CUSTOM   servo = comp.findBehaviour("ServoController") node.Dof.Controller = servo

Example. Calculate motion time and targets for motion

from vcScript import *   def OnRun():   comp = getComponent()   servo = comp.findBehaviour('ServoController')   # moves j1 to 200 and j2 to 350   servo.move(200, 350)     # moves j2 to 100 (index 0 = j1, index 1 = j2, ...)   servo.moveJoint(1, 100)     # J1: sets the target for next move but doesn't move yet   servo.setJointTarget(0,1200)   servo.setJointTarget(1,1400)     # calculate motion time according to given joint targets and joint speeds   # and accelerations   predicted_motion_time = servo.calcMotionTime()   print predicted_motion_time   if predicted_motion_time > 6:     # override given accelerations and speeds forcing the motion time to given value     servo.setMotionTime( 6.0 )     # call motion to set targets   servo.move()