Glossary of Robotic Terms:
| acceleration | how quickly an axis can accelerate. Since this is a limiting factor a robot may not be able to reach its specified maximum speed for movements over a short distance or a complex path requiring frequent changes of direction. |
| accuracy | how closely a robot can reach a commanded position. When the absolute position of the robot is measured and compared to the commanded position the error is a measure of accuracy. Accuracy can be improved with external sensing for example a vision system or Infra-Red. See robot calibration. Accuracy can vary with speed and position within the working envelope and with payload (see compliance). |
| actuator | a motor that translates control signals into mechanical movement. The control signals are usually electrical but may, more rarely, be pneumatic or hydraulic. The power supply may likewise be any of these. It is common for electrical control to be used to modulate a high-power pneumatic or hydraulic motor |
| algorithm | A set of procedures used to solve a problem. |
| analytical methods | Purely mathematical methods that do not require iteration. |
| application program | The set of instructions that defines the specific intended tasks of robots and robot systems. This program may be originated and modified by the robot user. |
| arm | An interconnected set of links and powered joints comprising a robot manipulator that supports and/or moves a wrist and hand or end-effector through space. The arm itself does not include the end-effector. See Manipulator, End-effector and Wrist. |
| articulated manipulator | A manipulator with an arm that is broken into sections (links) by one or more joints. Each of the joints represents a degree of freedom in the manipulator system and allows translation and rotary motion. |
| artificial intelligence (AI) | is the simulation of human intelligence processes by machines, especially computer systems. These processes include learning (the acquisition of information and rules for using the information), reasoning (using the rules to reach approximate or definite conclusions), and self-correction. |
| attended continuous operation | The time when robots are performing (production) tasks at a speed no greater than slow speed through attended program execution. |
| attended program verification | The time when a person within the restricted envelope (space) verifies the robot’s programmed tasks at programmed speed. |
| automatic mode | The robot state in which automatic operation can be initiated. |
| automatic operation | The time during which robots are performing programmed tasks through unattended program execution. |
| automation | A process is performed by using programmable machines. The process is not only supported by machines but these machines can work in accordance with a program that regulates the behavior of the machine. |
| automation solutions | The techniques and equipment used to achieve automatic operation or control. |
| autonomous | Operating independently without pre-programmed behaviors and without supervision from humans. |
| awareness barrier | Physical and/or visual means that warns a person of an approaching or present hazard. |
| awareness signal | A device that warns a person of an approaching or present hazard by means of audible sound or visible light. |
| axis | The line about which a rotating body (such as a tool) turns. |
| axis acceleration | The maximum acceleration that a particular axis can attain while the robot is loaded with the suggested payload. |
| ball screw | A device for transforming rotary motion to linear, or vice versa, incorporating a threaded rod portion and a nut consisting of a cage holding many ball bearings. |
| barrier | A physical means of separating persons from the restricted envelope (space). |
| base | The platform which supports the manipulator arm. |
| biomimetic | Mimicking life or natural biological systems. |
| business process automation (BPA) | The process of integrating enterprise applications, reducing human intervention wherever possible, and assembling software services into end-to-end process flows. |
| cam | A rotating part which, due to its eccentric center line, causes an in-and-out motion in any part pushing against it. |
| CAM | “Computer Aided Manufacturing” – the use of a computer to assist in the manufacturing process. |
| cartesian axis | Each of the mutually perpendicular lines which intersect at a common point called the origin, and which is used within a Cartesian coordinate system. When representing three planes, for instance, each axis is designated by the letters x, y, and z, respectively. Also called rectangular axis. |
| cartesian path tracking | The travel of the hand or end-effector of a manipulator in a path described by Cartesian coordinates. The manipulator joint displacements can be determined by means of an inverse Jacobian transformation |
| cartesian robot | Robot whose arm has three prismatic joints, whose axes are coincident with a Cartesian coordinator. |
| chassis | The parts making up a machine not including the body or casing. In the case of an automobile this would include parts such as the frame and engine but not the body surrounding these parts. |
| closed form | A problem formulation that does not require iteration for its solution. |
| cobot | a slang term to mean collaborative robot. A robot that is designed specifically to collaborate with humans. It is a “safe” mechanically passive robotic device that is intended for direct physical contact with a human operator. The operator supplies the power for motions, while the cobot responds with software-controlled movements. |
| collaboration | The active participation and work of the sub-systems towards accomplishing collaborative integration. It can be characterized as mandatory, optional, or conconcurrent, and it can occur internally or externally. |
| collaborative operation | “the introduction of a worker to the loop of active interaction during automatic robot operation.” |
| collaborative robot | a robot designed to work alongside humans |
| collision sensor | A sensor that detects and informs the controller to stop the robot prior to or during a crash. Other terms for this device include crash protection device, robot safety joint, and robotic clutch among others. |
| compensator | A remote device that involves multiple shear pads to help peg-in-hole operations. The shear pads are elastomers, also known as polymers and the device uses three to twelve of these shear pads. |
| computer aided design (CAD) | Computer Aided Design. Computer graphic applications designed to allow engineering of objects (or parts), which are to be manufactured. A computer is used as a tool to design schematics and produce blueprints, which enable the accurate production of the object. The CAD system enables the three-dimensional drawings of basic figures, exact sizing and placement of components, making lines of specified length, width, or angle, as well as satisfying varying geometric shapes. This system also allows the designer to test a simulated part under different stresses, loads, etc. |
| computer aided manufacturing (CAM) | (CAM) Computer software is used to design and/or alter the manufacturing process. |
| conservative motion | The end-effector and joints always move in their specific route. |
| control command | An instruction fed to the robot by means of the human-to-machine input device. See Pendant (Teaching). This command is received by the robot’s controller system and is interpreted. Then, the proper instruction is fed to the robot’s actuators, which enable it to react to the initial command. Many times the command must be interpreted with the use of logic units and specific algorithms. See Input Device and Instruction Cycle. |
| control device | An instrument that allows a person to have control over a robot or automated system for times such as startup or an emergency. |
| control program | The inherent set of control instructions that defines the capabilities, actions and responses of the robot system. This program is usually not intended to be modified by the user. |
| coordinated straight line motion | Control wherein the axes of the robot arrive at their respective end points simultaneously, giving a smooth appearance to the motion. The motions of the axes are such that the Tool Center Point (TCP) moves along a prespecified type of path (line, circle, etc.) |
| degrees of freedom (DOF) | The amount of values in a system possible of variation. A robotic joint is equal to one degree of freedom. |
| dexterity | Robotic arms with the capability to move their payload with consequently facility and quickness within the manipulator’s workspace |
| direct numerical control (DNC) | Numerical methods for determining optimal robot trajectories. Direct methods are designed to minimize the functional cost. Compared to indirect methods, direct methods prove to be quite robust and globally convergent, but computationally more expensive. |
| drive power | The source or means of supplying energy to the robot actuators to produce motion. |
| dynamic model | This model shows the forces causing the robot’s movement. |
| dynamics | Analysis of the causes of motion by the sources of forces and energy. |
| emergency stop | A method using hardware-based components that overrides all other robot controls and removes drive power from the robot actuators to bring all moving parts to a stop. |
| enabling device | The user activates the device allowing for the robot and machinery to move. When deactivated motion is stopped preventing harmful situations. |
| encoder | A feedback device in the robot manipulator arm that provides current position (and orientation of the arm) data to the controller. A beam of light passes through a rotating code disk that contains a precise pattern of opaque and transparent segments on its surface. Light that is transmitted through the disk strikes photo-detectors, which convert the light pattern to electrical signals. |
| end effector | The robot’s last link. The robot uses the end-effector to accomplish a task. The end-effector may be holding a tool, or the end-effector itself may be a tool. The end-effector is loosely comparable to a human’s hand. Examples may include gripper, spot-weld guns, arc-weld guns, spray- paint guns, or any other application tools. |
| end of arm tooling | Virtually anything that is placed on the end of a robot arm. |
| equality constraint | The end-effector’s change of position, movement and location must be equal to a certain number |
| error | The difference between the actual response of a robot and a command issued. |
| error recovery | An ability in intelligent robotic systems to detect a variety of errors and, through programming, take corrective action to resolve the problem and complete the desired process. |
| error absorbing tooling | A type of robot end-effector able to compensate for small variations in position and orientation. Especially suitable for assembly tasks, where the insertion of components demands tight tolerance positioning and orientation of the par |
| expandability | Being able to add resources to the system, such as memory, larger hard drive, new I/O card, etc. |
| factory automation | The process of integrating industrial machinery with the help of control software. This integration increases efficiency, productivity and quality while decreasing costs. |
| feedback | A signal from the robot equipment about conditions as they actually exist, rather than as the computer has directed them to exist. |
| fixed automation | “hard automation”, Automated, electronically controlled system for simple, straight or circular motion. These systems are mainly used for large production runs where little flexibility is required. |
| flexibility | The ability of a robot to perform a variety of different tasks. |
| flexible arm | A robot arm with mechanical flexibility, e.g., inflatable links or links made of mechanically flexible materials (contrast with Rigidity). |
| flexible automation | Designing and building of custom dedicated automated systems. |
| force control | A method of error detection in which the force exerted on the end-effector is sensed and fed back to the controller, usually by mechanical, hydraulic, or electric transducers. |
| force limited robots | A robot with a built-in “force torque sensor” that detects impact and abnormal forces. The sensor stop the robot when they are triggered. They tend to have rounder shapes, cushioned shells to absorb shock, all making them less harmful to humans |
| force torque sensor | The sensors that measure the amount of force and torque exerted by the mechanical hand along three hand-referenced orthogonal directions and applied around a point ahead and away from the sensors. |
| fully constrained robot | The number of equality constraints on the robot are equal to the number of independent joints |
| gantry robot | An overhead-mounted, rectilinear robot with a minimum of three degrees of freedom and normally not exceeding six. Bench-mounted assembly robots that have a gantry design are not included in this definition. A gantry robot can move along its x and y axes traveling over relatively greater distances than a pedestal-mounted robot at high traverse speeds while still providing a high degree of accuracy for positioning. Features of a gantry robot include large work envelopes, heavy payloads, mobile overhead mounting, and the capability and flexibility to operate over the work area of several pedestal-mounted robots. |
| gripper | The grasping hand of the robot which manipulates objects and tools to fulfill a given task. see end effector. |
| gravity loading | The force exerted downward, due to the weight of the robot arm and/or the load at the end of the arm. The force creates an error with respect to position accuracy of the end-effector. A compensating force can be computed and applied bringing the arm back to the desired position. |
| home position | A known and fixed location on the basic coordinate axis of the manipulator where it comes to rest, or to an indicated zero position for each axis. This position is unique for each model of manipulator. |
| hard automation | “fixed automtion”, Automated, electronically controlled system for simple, straight or circular motion. These systems are mainly used for large production runs where little flexibility is required. |
| hybrid | A robot that is part pick and place and part servo controlled, or has the same abilities. |
| industrial robot | A re-programmable multifunctional manipulator designed to move material, parts, tools, or specialized devices, through variable programmed motions for the performance of a variety of tasks (R15.06). The principle components are: one or more arms that can move in several directions; a manipulator; a computer controller that gives detailed movement instructions. |
| integrator | A company that combines and coordinates separate parts or elements into a unified whole using mechanical means. |
| intelligent robot | A robot that can be programmed to make performance choices contingent on sensory inputs with little or no help from human intervention |
| interlock | The control of a device starting or stopping is dependent upon the action of another device. |
| internal sensor | An apparatus within the manipulator arm that sends information on motion to a control unit. |
| inverse kinematics | Determination of a joint’s overall change in position based on restrictions on the end-effector’s motion of a robot. |
| iteration | A method of solving a problem by repeating the same procedure to find a more exact solution. A new version of a piece of computer hardware or software. |
| jacobian | The matrix of first-order partial derivatives. For robots, the Jacobian relates the end-effector velocity to the joint speeds. |
| joint coordinate system | The set of all joint positions values for Cartesian robots. |
| jointed arm robot | A robot whose arm consists of two links connected by “elbow” and “shoulder” joints to provide three rational motions. This robot most closely resembles a human arm. |
| kinematic influence coefficients | These coefficients describe the total influence the N input joints have on the motion of the robot and allow a direct statement of the complex and coupled nonlinear differential equations controlling the response of the system. |
| kinematics | The branch of mechanics concerned with the motion of objects without reference to the forces that cause the motion. The study of the mapping of joint coordinates to link coordinates in motion, and the inverse mapping of link coordinates to joint coordinates in motion |
| limiting device | A device that restricts the maximum envelope (space) by stopping or causing to stop all robot motion and is independent of the control program and the application programs. |
| load capacity | The maximum total weight that can be applied to the end of the robot arm without sacrifice of any of the applicable published specifications of the robot |
| manipulator | A mechanism, usually consisting of a series of segments, or links, jointed or sliding relative to one another, for grasping and moving objects, usually in several degrees of freedom. It is remotely controlled by a human (manual manipulator) or a computer (programmable manipulator). The term refers mainly to the mechanical aspect of a robot. |
| manual programming | Programming by physically moving the robot to create sets specific tasks and limits on the robot. |
| maximum space envelope | The largest area that all parts of the robot cover with its various movements. |
| mechanical grip devices | The most widely used type of end-of-arm tooling in parts-handling applications. Pneumatic, hydraulic, or electrical actuators are used to generate a holding force which is transferred to the part via linkages and fingers. Some devices are able to sense and vary the grip force and grip opening. |
| mobile robot | A type of robot with its own engine or power able to move without constraints on its path. |
| motion axis | The line defining the axis of motion either linear or rotary segment of a manipulator |
| nanorobotics | The science of designing, building, and applying robots capable of interaction with atomic- and molecular-sized objects |
| normalize | Scaling a number of factors so that they will be of similar magnitudes. |
| numerical methods | Iterative methods of solving problems on a computer. Numerical methods may have an analytical basis or they may involve heuristics. |
| off-line programming | Developing robot programs partially or completely without requiring the use of the robot itself. The program is loaded into the robot’s controller for subsequent automatic action of the manipulator. An off-line programming system typically has three main components: geometric modeler, robot modeler, and programming method.Often it is associated with robot simulation to try to debug it before implementation. The advantages of off-line programming are reduction of robot downtime; removal of programmer from potentially hazardous environments; a single programming system for a variety of robots; integration with existing computer aided design/computer-assisted manufacturing systems; simplification of complex tasks, and verification of robot programs prior to execution. |
| on-line programming | The use of a teach pendant for teach programming, which directs the controller in positioning the robot and interacting with auxiliary equipment. It is normally used for point-to-point motion and controlled path motion robots, and can be used in conjunction with off-line programming to provide accurate trajectory data. |
| operator | The person designated to start, monitor and stop the intended productive operation of a robot or robot system. An operator may also interface with a robot for productive purposes. |
| optimization | Calculating the independent variables in a function so as to generate the best function value for a given set of conditions. Optimization usually involves maximizing or minimizing a function. |
| 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. Angular position of an object with respect to the robot’s reference system. See roll, pitch, and yaw. |
| palletizing | The process of placing parts in different positions on a pallet. |
| parallel robot | Robot whose arms have concurrent prismatic or rotary joints. |
| pick and place robot | A simple category of robot used to pick parts and place them down somewhere else. |
| pitch | Rotation of the end-effector in a vertical plane around the end of the robot manipulator arm. see roll and yaw |
| point to point motion | A type of robot motion in which a limited number of points along a path of motion is specified by the controller, and the robot moves from point to point rather than in a continuous, smooth path. |
| pose | Alternative term for robot configuration, and describes the linear and angular position. The linear position includes the azimuth, elevation, and range of the object. The angular position includes the roll, pitch, and yaw of the object. See roll, pitch, and yaw. The robot’s joints position for a particular end-effector position and orientation within the robot’s workspace. Specific positions are named according to the tasks the robot is performing; for example, the home pose, which indicates the resting position of the robot’s arm |
| position sensor | Device detecting the position of the rotor relative to the stator of the actuator. The rotor speed is derived from the position information by differentiation with respect to time. The servo-system uses this sensor data to control the position as well as the speed of the motor. In general, one of two sensor types is used: the pulse coder type, also known as digital encoder or the resolver type |
| proprioception | The unconscious perception of movement and spatial orientation arising from stimuli within the body itself. In humans, these stimuli are detected by nerves within the body itself, as well as by the semicircular canals of the inner ear. In robots, encoders are used, either relative (a place/position/orientation between two points) or absolute (at an exact point) |
| reach | The distance which a robot’s end-effector can reach in at least one orientation. |
| rebuild | Improvements are made to parts of the robots to return it to its original appearance, performance and life expectancy as closely as possible. |
| redundancy | The number of independent variables is more than the number of constraints. |
| remote compliance center (RCC) | Used to decouple linear and rotational motion. All compliance structures have a center though the remote compliance center is projected outward. |
| repeatability | how well the robot will return to a programmed position. This is not the same as accuracy. It may be that when told to go to a certain X-Y-Z position that it gets only to within 1 mm of that position. This would be its accuracy which may be improved by calibration. But if that position is taught into controller memory and each time it is sent there it returns to within 0.1mm of the taught position then the repeatability will be within 0.1mm. |
| restricted envelope space | A part of the maximum envelope in which the distance determines the boundaries the robot moves after the limiting device is activated. |
| robot system integrator | A business that merges robots, peripherals, and manufacturing machinery into a production system that functions as a single unit to perform manufacturing tasks. See Integrator |
| robotic rotary joint | Consisting of a stationary part connected to the arm of the robot and a rotating part connected to the wrist and tool allowing for electrical and pneumatic cables to stay in place while cables required for the tool are free to rotate. Electricity is provided by the used of a slip ring. |
| robotic self motion | The robot maintains the position of the end-effector while allowing other parts on the robot to move. |
| roll | Rotation of the robot end-effector in a plane perpendicular to the end of the manipulator arm. See pitch, and yaw. |
| sensor | A device that responds to physical stimuli (such as heat, light, sound, pressure, magnetism, motion, etc.) and transmits the resulting signal or data for providing a measurement, operating a control, or both. |
| speed | how fast the robot can position the end of its arm. This may be defined in terms of the angular or linear speed of each axis or as a compound speed i.e. the speed of the end of the arm when all axes are moving. |
| swing | a robot’s rotational movement with respect to it’s centerline |
| teach mode | The control state that allows the generation and storage of positional data points affected by moving the robot arm through a path of intended motions. |
| three roll wrist | A wrist with three interference-free axes of rotational movement (pitch, yaw, and roll) that intersect at one point to permit a continuous or reversible tool rotation which simplifies the required end effector design by its extensive reachability. It was originally designed by Cincinnati Milacron, Inc. |
| touch sensor | A sensing devive which senses physical contact with an object, thus giving the robot a “sense of touch”. The sensor respond to contact forces that arise between themselves and objects. |
| torque/force controller | A control system capable of sensing forces and torques encountered during assembly or movement of objects, and/or generating forces on joint torques by the manipulator, which are controlled to reach desired levels. |
| vacuum cup hand | An end-effector for a robot arm which is used to grasp light to moderate weight objects, using suction, for manipulation. Such objects may include glass, plastic; etc. Commonly used because of its virtues of reduced object slide slipping while within the grasp of the vacuum cup. See End-Effector. |
| velocity level | The measure of variation of joint position over time. Single integration yields the overall change in position. Single differentiation yields the change in joint speed over time. Refer to acceleration-level and position-level. |
| vertical stroke | The amount of vertical motion of a robot arm from one elevation to the other. |