Glossary

Collider

A collider is a geometric representation of an object used in motion planning and simulation to define its physical boundaries for the purpose of collision detection. In robotic systems, colliders are used to model the shape, size, and position of obstacles, tools, or robot parts within a workspace.

Colliders are essential for planning collision-free paths by informing the motion planner which areas of space should be avoided. Common shapes include spheres, boxes, and cylinders, typically defined by their position, size and orientation.

Code example:

# Sphere collider
sphere_collider = models.Collider(
    shape=models.ColliderShape(models.Sphere2(radius=100, shape_type="sphere")),
    pose=models.Pose2(position=[-100, -500, 200]),
)

Collision-free motion

A planned trajectory that avoids intersecting with any collider defined in the environment.

Collision scene

A collection of colliders and their spatial relationships used to simulate an environment for motion planning and collision detection.

Degrees of freedom (DoF)

Degrees of freedom (DoF) is a term used in robotics to describe the number of independent movements a robot can make. For example, a 6DoF robot can move in six different ways: three translational movements (X, Y, Z) and three rotational movements (roll, pitch, yaw). In the context of Wandelbots NOVA, the term is used to describe the number of joints in a robot arm or the number of axes in a motion group.

Flange

A flange is the end part of a robot arm where tools or end effectors are attached.

Joints

A joint defines to which degree a robot arm can move. Typically, this is represented via an angle or displacement value. Think of it as the exact angles of body parts a human dancer needs to be in to perform a specific dance move. A complete set of joint values (one per joint of the robot arm) is called a joint configuration which determines the precise internal geometry of the robot.

Joints are often used in low-level motion commands where precise control over robot motion is necessary. Joint configurations are specific to each robot model and cannot be transferred across different robot types.

Joint trajectory

jointTrajectory in the Wandelbots NOVA API is a time-parameterized sequence of joint positions for a motion group, sampled at the controller’s cycle time. It defines how each joint of the robot should move over time to execute a planned motion.

The Wandelbots NOVA API samples joints positions, times and locations.

Location (on a path)

The location on a path is a scalar value that indicates progress along a trajectory. It ranges from 0 to n, where n is the number of motion commands used in planning. Integer values correspond to the start of each motion command, while fractional values indicate positions within the segments,

Motion command

A motion command is a high-level instruction that defines a specific type of movement for a robot. It contains the path, optional blending, and limits override.

Motion group

A motion group is the robot arm or an external axis controlled by the robot controller which they are connected to. Commonly referred to as a robot. The API can interact with virtual and physical motion groups. Learn more about what a Wandelbots NOVA motion group is here.

Playback speed

Playback speed is a scaling factor applied to the velocity profile of a trajectory during execution. It allows adjusting the speed of the robot’s motion without altering the shape of the trajectory.

Poses

A pose defines a position and orientation in 3D space, typically relative to a coordinate system, e.g. world, robot base, or a tool frame. Think of it as the exact position and orientation in the room where a human dancer needs to be in to perform a specific dance move.

Poses are often used in high-level, task-oriented motion commands, such as placing a tool tip at a precise location or following a path relative to an object.

Robot

A robot is common language for motion group. A motion group is the robot arm or an external axis controlled by the robot controller which they are connected to. Commonly referred to as a robot. The API can interact with virtual and physical motion groups.

Robot cell

A robot cell contains one or more robot controllers as well as connected periphery. Learn more about what a Wandelbots NOVA cell is here.

Robot controller

A robot controller mainly takes care of the networking, kinematics and motion control of the robots and periphery connected to it. Learn more about what a controller is on Wandelbots NOVA here.

Rotation

Wandelbots NOVA API uses two different ways to describe a 3D rotation: Rotation vector in radians and quaternions.

Simulation

Simulation is an accurate virtual representation of a robot cell. It is used to test robot programs before deploying them to a physical robot cell.

With Wandelbots NOVA, simulation is uniquely associated with using NVIDIA Isaac Sim. Learn how to simulate with NVIDIA Isaac Sim x Wandelbots NOVA here.

Standstill

Standstill is a state emitted by the execution websocket of the Wandelbots NOVA API when the robot has come to a complete stop. The controller reports no further motion. Either the motion has been completed or paused.

TCP

Tool center point of an end effector. The default tool center point is the flange where the tool is attached to the motion group. When attaching a tool, you need to define a corresponding tool center point in relation to the flange by specifying a position offset and a relative direction. To execute motion commands, the API uses the TCP as reference for movements, e.g. the tip of a dispenser or the center of a sanding disc.

Virtualization

Virtualization in Wandelbots NOVA describes all processes and results connected to creating a virtual impression of a physical robot cell. This virtual impression is used to create robot programs and test them in a virtual environment before deploying them to a physical robot cell.

The 3D view in Robot Pad offers a visual representation of the virtual cell and the planned paths.

Not to be confused with simulation.