The minStop and maxStop fields define the hard limits of the joint. The values of the minStop and maxStop fields are also defined with respect to the zero position. The values passed to the wb_motor_set_position function are specified with respect to the zero position. If its value is zero, then the Joint's child is by definition set with its initial translation and rotation.įor a joint with one, two or three rotational degrees of freedom (e.g., HingeJoint, Hinge2Joint, BallJoint), the position field value is the rotation angle around one of the joint axes that was applied to the Joint's child initially in zero position.įor a slider joint, position is the translation length along the sliding axis that was applied to the Joint's child initially in zero position.įor example if we have a HingeJoint and a position field value of 1.5708, this means that this HingeJoint is 90 degrees from its initial rotation with respect to the hinge rotation axis. The position field is a scalar representing an angle (in radians) or a distance (in meters) computed with respect to the initial translation and rotation of the Joint's Solid child. The position of a rotational joint ( HingeJoint, Hinge2Joint or BallJoint) is expressed in radians while the position of a linear joint ( SliderJoint) is expressed in meters. The staticFriction field defines add a simple static friction force opposed to the joint motion. These fields are described in more detail in the 'Springs and Dampers' section, see below. The springConstant and dampingConstant fields allow the addition of spring and/or damping behavior to the joint. These fields are described in more detail in the 'Joint Limits' section, see below. The minStop and maxStop fields specify the position of physical (or mechanical) stops. Similarly, when changing the position field of a JointParameters node in a text editor, you should take care of also changing the corresponding rotation or translation field accordingly. When changing the position field from the Webots scene tree, Webots also changes the corresponding rotation (for a hinge or ball) or translation (for a slider) field in the endPoint solid of the parent joint node to keep the consistency of the model. The position field represents the current position of the joint, in radians or meters.įor an hinge or ball, it is the current rotation angle in radians.įor a slider, it is the magnitude of the current translation in meters. Unlike the other joint parameters node, it has no anchor. The JointParameters node is a concrete base node used to specify various joint parameters related to an axis along which, or around which, the motion is allowed.Īs an instantiated node it can be used within the jointParameters field of SliderJoint or within the jointParameters2 field of Hinge2Joint or BallJointParameters and jointParameters3 field of BallJointParameters. Note: The axis field may change in a derived class.įor instance, the axis default value of an HingeJointParameters is 1 0 0, and there is no axis field in a BallJointParameters Description

Webots nao joint names