What is a Transducer?

A transducer is essentially a device that converts some form of energy into another form. Common types of transducers used in industrial applications can include sensors used to measure temperature, pressure, force, strain, liquid levels and flow rates, and electrical conductivity among others. In motion control applications, transducers can refer to... [Read more]

What is a Gear?

The primary task of a gear is to mesh teeth with another toothed part to transmit torque or to translate rotation. Thus, geared devices can change the speed, torque, and direction of a power source. When two gears of unequal number of teeth combine, it results in a mechanical advantage, with both the rotational speeds and the torques of the two gears... [Read more]

What are Motion Control Networks?

Multi-axis motion control typically uses event-based synchronization. This level of synchronization is defined as scheduled, absolute hard delivery of time-critical cyclic data across the network. Delivery variability must be less than 1 µs, which is also known as jitter. While a number of networks exist for “motion control,” it is important to... [Read more]

What is Linear Motion?

Linear motion is an area of motion control encompassing several technologies including linear motors, linear actuators, and linear rolling guides and bearings, among others. Linear motors Traditional linear motors are basically a permanent magnet rotary motor rolled out and laid flat. It’s as if the stator and rotor were cut along a radial plane and... [Read more]

What is a Motor Drive?

Defining a drive can be a bit tricky. Some drives are wholly incorporated into the controller, so that the profile generation takes place in the controller as well as the torque command for the motor. On the other hand, a drive can also refer to the specific power electronic circuitry needed to drive the motor. Electric motors that drive industrial... [Read more]

What are Integrated Servomotors?

A newer subcategory of servomotor is often called the integrated servomotor. In this type of design, the motor itself is combined with the other essential components of a complete motion control system including the feedback device (generally an encoder), the amplifier or motor drive, a communication port and the motion controller itself. Such systems... [Read more]

What are Retaining Rings?

Retaining rings are fasteners that hold together components on a shaft when installed in a groove. There are three main types of retaining rings; tapered section, constant section and spiral. Tapered section rings are characterized by their decreasing thickness from the center of the ring out to the ends. These rings can be mounted either axially or... [Read more]

What is a Servomotor?

Nailing down precisely what a servomotor is can be a tricky exercise, but basically the hallmark of any servomotor is the presence of feedback and closed-loop control. Servomotors are able to provide precise control of torque, speed or position using closed-loop feedback. They also have the ability to operate at zero speed while maintaining enough torque... [Read more]

What are Flexible Couplings?

Couplings join together two shafts as a way of transmitting power from one to the other. It is part of the drivetrain which may include other power transmission components such as lead screws or ball screws, gearboxes, belts and pulleys or chains. There are two fundamental types of couplings; rigid and flexible. Rigid couplings are generally used in... [Read more]

What is a Servo Controller?

More specific types of controllers, such as servo controllers, are used to control servomotors. When dealing with servo systems, it’s important to note that definitions for servomotor, servo system, and servo controllers can differ widely throughout industry. When selecting a servo system for an application, it’s best to ask suppliers what exactly... [Read more]

What are Programmable Logic Controllers?

Programmable logic controllers,or PLCs, are highly specialized, programmable microprocessor-based controllers used to control a specific application on a machine or a process. They are used in automation and manufacturing to control assembly lines and machinery on factory floors as well as many other types of mechanical, electrical, and electronic equipment... [Read more]

Variable frequency drives

Variable-frequency drives, or VFDs, are a means of controlling the speed of an ac motor, typically an ac induction motor. It does so by varying the frequency of the power source. VFDs operate by switching their output devices, which can be transistors, IGBTs, or thyristors, on and off. VFDs can be either constant voltage or constant current. Constant... [Read more]

Motion Sensors

Sensors for motion applications can include position sensors, speed and proximity sensors. Linear position sensors are used to determine the position of a mechanical component in a broad range of applications. Linear position sensors use an inductive oscillating circuit coupling positioned between the actuator and sensor. Emitter and receiver coil systems... [Read more]

Wave springs

At its most basic level, a spring is a device used to store mechanical energy. Although often out of sight, springs play an important role in many motion control applications. They are used in gear assemblies, actuators, rotary unions, and different kinds of clutches, among other applications. There are many different varieties and shapes and sizes... [Read more]

Motion controller

Motion controllers are the brains of any motion control system. In feedback-based systems, they take an input command from the user, compare it with a feedback signal from the motor, and take corrective action to bring the output (or actual position) and input (or desired position) in line with one another, ideally with little or no error. A motion... [Read more]

Incremental encoders

Incremental encoders, like absolute encoders, are used to track motion as well as to determine speed and position. Incremental encoders generally supply square-wave signals in two channels, A and B, which are offset by 90 degrees, or out-of-phase by 90 degrees. This helps in determining the direction of rotation. The output signals of an incremental... [Read more]

Torque limiter

Torque limiters protect equipment or loads from excessive torque. In essence, they are used to shut down a machine and dissipate any rotational energy without causing damage to the machine. Often, systems operating at low speeds can develop a large quantity of torque. In the event of a malfunction, this excess torque can damage machine components such... [Read more]

Stepper motors

One of the most common motors used in motion control applications is the stepper motor. These motors are used mostly in positioning applications and have the advantage of being able to be very accurately controlled for the most precise positioning applications, down to fractions of a degree without the use of feedback devices such as encoders or resolvers.... [Read more]

Bellows Couplings

One form of flexible coupling with very low and near zero-backlash is the bellows coupling. The key benefits of bellows couplings include misalignment compensation and precise transmission of velocity, angular positioning and torque. Bellows couplings are known for their exceptional torsional rigidity, which allows for flexibility in dealing with axial,... [Read more]

Flat Cabling

An alternative to flexible cabling in some motion applications are flat cables. These cables can incorporate any variety of power, signal, and video conductors in a single compact cable. In addition to every type of electrical conductor, flat cables can also include tubing for air or liquids, and even fiber optics. By incorporating all these elements... [Read more]

Machine Controller

In the most general sense, a controller receives some type of input and produces outputs for some device, most commonly an electric motor. More specifically, machine control, unlike a more specific type of controller such as a motion controller, refers to the control of an entire stand-alone machine such as a CNC machine, packaging machine, or even... [Read more]

Absolute encoders

Encoders can be either absolute or incremental. Absolute encoders have a unique code for each shaft position. Or in other words, every position of an absolute encoder is distinctive. The absolute encoder interprets a system of coded tracks to create position information where no two positions are identical. Another feature is that absolute encoders... [Read more]

Roller chains

In any motion control system, the object is ultimately to move some kind of load. The component in the motion system that converts electrical energy into mechanical energy is the motor. But the task doesn’t end there. A motor’s output shaft has to connect somehow to whatever the load is. This final connection can take many forms. Some of the most... [Read more]

HMI software

Human machine interface (HMI) software gives machine operators a way to interact with and manage a system. This interaction is through a graphical user interface (GUI), which facilitates information exchange and communication between two types of HMIs; a supervisory level and a machine level. Generally, HMI software is designed for either machine level... [Read more]

AC motors

Motors can be classified as either ac – alternating current, or dc – direct current, motors. An ac motor, like any electric motor, converts electrical energy to mechanical energy. AC motors take as their input an ac current, but differ from dc motors in that there is no commutation involved, and can be single or multi-phase. Because ac motors... [Read more]

Brushless dc motors

A brushless dc (BLDC) motor is essentially a dc motor without the mechanical commutation of the brushed dc motor. BLDC motors are powered by direct current and have electronic commutation systems instead of the mechanical brushes and commutators used in brushed dc motors. All dc motors generate a magnetic field, either via electromagnetic windings or... [Read more]

Gearing

Gearmotors Gearmotors are an all-in-one combination of an electric motor and one or more pairs of gears (which is also known as a gearbox). A gearmotor simplifies combining a motor with a gear reducer system. Planetary gears Planetary gears consist of one or more outer gears, or planet gears, revolving about a central, or sun gear. Typically, the planet... [Read more]

Flexible cabling

Flexible cables, or continuous-flex cables, are cables specially designed to cope with the tight bending radii and physical stress associated with motion control applications. These highly flexible cables were developed with unique characteristics to differentiate them from standard designs. These are sometimes called chain-suitable, high-flex, or continuous... [Read more]

Bearings

Efficient linear or rotational movement usually relies on some type of bearings. In fact, most of the machines built today incorporate bearings—and without them, maintenance technicians would face the frustration of constantly replacing parts that wore out due to friction. The basic concept behind a bearing is that things roll more easily than they... [Read more]

Linear motion bearings

This class of bearings generally uses a pad, bushing, or roller system to carry a load on a rail that need not be a straight line. The rail can be most any length, although that dimension is limited by the actuator. The durability of the bearing is determined by the load and required speed. Furthermore, rails can generally be any profile – simple... [Read more]

Lead Screws

When it comes to translating the rotary motion of a motor to linear motion, there are many different ways of accomplishing this task. Often times in the world of motion control, the battle between the different methods and technologies can get quite contentious. However, as a rule, it’s best to remember that specific applications are better for some... [Read more]

Cable Carriers

Motion control systems can vary from simple, straightforward single-axis direct-drive systems with little wiring to large and complex multi-axis robotic systems with a hornet’s nest of cables. This is usually where cabling, which was an afterthought, now takes center stage. Especially where there are lots of cables and wiring, cable management becomes... [Read more]

Ball Screws

Ball screws are mechanical devices that convert rotational motion to linear motion with a minimal amount of friction. There are several components to a ball screw including a nut and a screw with helical grooves and balls that roll between the nut, the screw and the grooves, while the screw or nut is rotating. Balls are routed into the ball return system... [Read more]

DC Motors

A direct current – dc  motor is an electric machine that converts electrical energy to mechanical energy. DC motors are one of two general types of motors, the other being the alternating current – ac motor. DC motors have a few basic components including the commutator, armature, a stator and a rotor. All dc motors generate a magnetic... [Read more]