KINOVA
®
Gen3 Ultra lightweight robot
User Guide
72
Gravity Compensation
The gravity model computes the forces and torques due to gravity at each joint. The
gravity torques are then subtracted from the measured torques, resulting in a gravity-
free torque vector.
Joint Angle
Describes the position of every joint of a robot as as series of angles.
Joint Space
The set of all possible joint positions.
Null Space
The mathematical space of joint speeds where the robot can change its configuration
(generate joint speed and motion) without changing the end-effector pose (Null Twist at
the end effector).
Orientation
• The angle formed by the major axis of an object relative to a reference axis. It must be
defined relative to a three-dimensional coordinate system, i.e. the angular position of an
object with respect to the robot's reference system.
• The end effector's position consists of two things, a translation (x, y and z) and an the
orientation that can be expressed in several ways. Think of it as a vector. This would be the
orientation of this vector.
Path
The continuous locus of points (or positions in three dimensional space) traversed by the
tool center point and described in a specified coordinate system.
Path (Angular)
The set of at least two angular poses, through which the actuator values angles should
pass during motion.
Path (Cartesian)
The set of at least two Cartesian poses, through which the tool of the robot should pass
during motion.
Pose
Describes the position and orientation of a rigid body in Cartesian space.
Position
The definition of an object's location in 3D space, usually defined by a 3D coordinate
system using X, Y, and Z coordinates.
Quaternion
A quaternion is a group of four numbers used to express a vector's orientation.
Reference Frame
A system of geometric (coordinate) axes in relation to which measurements of size,
position, or motion can be made. Robotic manipulators normally include several
strategically placed reference frames, located at the base, joints and end effector.
Tool Frame
A coordinate system attached to the end effector of a robot (relative to the base frame).
