This month’s update to our Technical Articles includes “What is a Multiturn Encoder?”.

A multiturn encoder is a rotary position sensor that measures angles from 0 to 360 degrees, as well the number of complete revolutions, known as Turn Count. Learn about types of Multiturn sensor technologies, including Geared Multiturn, Battery Backup Multiturn, Energy Harvesting Multiturn and Absolute Encoder with Non-volatile Turn Count Storage.

Read the article in full.

This month’s update to our Application Success Stories includes Gimbals for Search and Rescue Helicopter.

This application story describes a solution to the challenge of search and rescue missions operating in a variety of locations from sea to mountain tops, day or night, and in all types of weather conditions. Search and rescue operations rely on state-of-the-art technology, including high performance gyro-stabilized searchlights and optoelectronic systems, to move quickly and accurately – assisting in mission completion and success. Celera Motion’s Ultra IncOder™ advances the design of robust, high resolution and high accuracy pointing of stabilized gimbal payloads for these searchlight and optoelectronics systems.

Read the success story in full.

Servo drives, also called amplifiers, take the command signals for position, speed, or torque requirements, and alters the output voltage applied to the servo motor utilizing closed loop control.

A servo system is comprised of multiple components, including a master controller, a motor, and feedback devices. Among them, the servo drive is the most critical component.  The communication between controllers and additional devices is enabled by a simple digital and analogue I/O or digital fieldbus communication, such as EtherCAT and CANopen, as well as other industry standard protocols. Motor technology is continuously evolving to offer optimal results for every application. Servo drives evolve along with them to maintain the ability to provide the best control features for each type of motor.

DC Servo Drives for Industrial Automation

Servo Drives in Industrial Automation Robots

Different Servomechanism Control Configurations

Servomechanisms are automated control systems that are employed in a wide range of applications.  These control systems can work in an open-loop or in closed-loop fashion. With a closed-loop architecture, you can achieve enhanced precision and reliability better than in an open-loop architecture because multiple feedback sensors can be used to account for errors and external disturbances affecting the system.

Servo drives are typically employed to control the torque, speed and/or position of brushless servo motors. They are an incredibly important element in determining the overall performance of the system and are available in a wide range of formats that are well-suited for static and mobile applications spanning many industries such as:

  • Laboratory automation
  • Industrial automation
  • Robotics
  • Satellite communication
  • Aerospace and defense
  • Offshore
  • Ground mobile

DC servo drives are created to offer full integration with applications and ideally, the drives should be positioned close to the actuator or motor.

When servo drives are compared to straight power amplifiers, they offer many advantages for automatic machining systems such as enhanced positioning, motion control and speed.

How Motion Control Applications Use Servo Drives

Some motion control applications employ analog servo drives which are a traditional, widely used, technology. However, digital servo drives can communicate with an entire network. Digital DC servo drives provide enhanced capacity for performance and configuration, and some may even be able to store motion indexes and sequences in their memory.

Servo Drives from Celera Motion

Celera Motion manufactures high-performance, high-power density, miniature servo drives along with powerful control software. Our expertise and focus in next-generation power design has led to the creation of some of the smallest and most energy efficient servo drives for precision motion control without sacrificing performance and efficiency.

If you would like to find out more about our servo drives, contact us today to speak to an expert. Click here to read about how our servo drives are used in industrial robotics.

A servo drive is an electronic amplifier used in servomechanisms to regulate the current/voltage output to the motor. Servo drives are part of a continuous feedback loop between a sensor (or multiple sensors) monitoring the motor and the motion controller, receiving low-voltage commands from the controller, and amplifying them to achieve a given result.

Although the principal role of a servo drive is to control the motor dependent servo loop, different protocols apply to different mechanical systems.

What is a Servo Drive?

Servo Drive and Servo Motor combination

Different Servomechanism Control Configurations

Standalone axes that are not precisely coordinated with other axes often utilise a loosely coupled distributed control configuration in which the servo drive carries out path planning, as well as the position and velocity control loops. This reduces the computational strain on the master controller and allows for a faster network.

Closely integrated networks of coordinated axes with load-dependent servo loops and dynamic loads that change in real-time require a tighter coupling, either as a distributed or a centralized control network. Tightly coupled configurations are required for high-performance systems. Distributed control networks give path planning tasks to the master, while centralized controls limit servo drive tasks to current control alone.

Where are Servo Drives Used?

Servo Drives for Exoskeleton Robotics

Ultra-small servo drives with high power density provide the low-profile necessary for OEMs working on innovative exoskeletons for biomedical, industrial, or military applications. These wearable solutions require tight integration with good standby power consumption and minimal heat generation while maintaining high performance to meet critical KPIs in the growing exoskeleton market.

Servo Drives for Industrial Robotics

Process automation has proven vital to ongoing profitability in industrial sectors, with robotics assemblies changing the face of the production line forever. These multi-axis robotic systems require tight integration and optimized heat dissipation. Ultra-precise servo drives are essential components throughout the industrial robotics sector – delivering the highest performance and efficiency while limiting energy loss through heat dissipation for overall system optimization.

Servo Drives for Radar Antennas

Radar antenna applications including airborne mobile Satcom antenna systems, and radar turntables, rely on extremely accurate and highly stable motion controllers to ensure continuous target tracking and/or satellite image locking. Servo drives designed for high-speed broadband applications are engineered for high performance in harsh environmental conditions, ensuring continued operation in extended temperature ranges, extreme mechanical/thermal shock and vibration.

Servo Drives for Robotics Surgery

Miniature, lightweight, high-performance servo drives are central to the ongoing revolution in surgical robotics, providing the means for conducting surgical procedures that mitigate risks to patients. Low latency, ultra-small servo drives allow robotic systems to be precise, compact, and efficient. The low latency and lag results in instant replication from the surgeon’s console to the surgical robot, delivering the precision needed for success.

Servo Drives for UVD Robots

Automated guided vehicles (AGVs) used for disinfection purposes are now commonly referred to as UVD robots. Optimal power efficiency and proper battery management directly translates to an increased operation life expectancy of the vehicle. Allowing UVD robots to operate for longer periods uninterrupted can dramatically accelerate disinfection processes. Servo drives with optimal power efficiencies and proper battery management are important requirements of UVD robots.

Interested in Celera Motion Servo Drives?

Celera Motion is committed to delivering rapid and reliable motion control solutions for a large variety of market segments and applications. Our precision components include a range of servo drives, suitable for the most demanding operating conditions in modern industry. Interested in more information? Contact a member of the team today.

Complexity in mechanical assemblies is not necessarily a good thing. More moving parts typically translates to more potential points of failure, greater inefficiencies, and relatively poor reliability. There is a reason why the power transmission is the most common cause of vehicular faults and the largest source of mechanical losses. This is because multiple integrated gears and shafts are used to drive the load. Additionally, the gearbox can contribute objectionable amounts of noise, vibration, and harshness (NVH) which is unappealing to consumers.

Direct drive technology has been available for a long time, but it has experienced significant uptake in recent years in applications varying from the automotive sector through to clean energy generation. So, what benefits do direct drive motors offer over conventional motors?

What is a Direct Drive System?

A direct drive motor describes any linear or rotary motor that is directly connected to the load, driving it without means of mechanical transmission. Instead of mechanical couplings, direct drive systems use permanent synchronous magnets and stator windings to produce an applied electromagnetic field to directly transmit motor power without intermediate components.

5 Benefits of Direct Drive Motors

  1. Compactness—Direct drive motors offer significant design advantages, particularly due to large through hole diameters (rotor ID) and low axial height. As direct drive motors consist of just two parts—the stator and rotor—they can be engineered to extremely compact form factors.
  2. Power—With optimized motor constant, direct drive motors offer exceptional power density. In rotary motors this represents elite torque density torque-carrying capabilities with a small footprint and low energy consumption.
  3. Performance—Direct drive systems use a choice of high resolution positional feedback devices (optical encoders, capacitive encoders, brushless resolvers, etc.) for extremely accurate dynamics and speed, resulting in dramatic improvements to precision.
  4. Reliability—The low part count of frameless direct drive motor kits significantly increases component reliability. By eliminating additional mechanical elements, the cost of assembly is significantly reduced while detrimental effects like backlash or wear are avoided.
  5. Low Maintenance—The high reliability of direct drive systems also translates to reduced maintenance requirements. In many cases, frameless motors can run for their entire lifetime without maintenance cycles—which results in reduced downtimes thus maximum throughput and performance over the full service period of the part.

Direct Drive Motors from Celera Motion

Although direct drive systems represent a clear improvement over conventional systems, a lack of familiarity with synchronous magnet technologies often leads machine builders to stick by classical systems. At Celera Motion, we have developed a range of pre-engineered direct drive solutions design for optimal system integration. Our goal is to reduce the friction associated with onboarding new technologies and to provide tangible returns for end-users in a range of application areas.

Our Omni+ Series direct drive motors are optimised to fit into various actuation systems or rotary stages with custom windings and form factors available to meet specific application requirements. Interested in learning more? Contact a member of the Celera Motion team today.

The word “robot” was first introduced to the English language in the 1920s and was connected to sci-fi connotations. For many, “robot” still brings to mind futuristic applications, but despite the origin robots are very much real. Today, the word is used to refer to machines capable of carrying out complex tasks automatically. Industrial robots play a vital role throughout many different market sectors, where robots are used to perform a large variety of tasks with speed and precision. In this article we take a look at some industrial robotics applications.

Industrial Robotics

Industry and robotics go hand in hand: robots were initially developed with industrial applications in mind. Industrial robotics remains one of the primary facilitators of the advancement of industry – the articulated robot arm is practically synonymous with the modern-day production line.

Industrial robotics has revolutionized many industries by providing systems capable of carrying out a range of tasks with advanced speed and precision. These include welding, 3D product inspection, warehouse handling, and electronics manufacturing among countless other applications.

AGV Robots

Autonomous guided vehicles (AGVs), a mainstay of robotics, can aid in a range of industrial applications, often used for transporting raw materials or order fulfillment processes. Utilizing a variety of navigation systems, from simple magnetic tape to complex LiDAR-based sensing arrays and IoT interconnectivity, AGVs can be programmed to carry out routine, repetitive tasks that are labor intensive and time-consuming.

AGVs are increasingly replacing forklift vehicles for transporting pallets in warehouses, alongside heavy equipment carriers for large assembly transports. This can represent a significant cost-saving over the long-term, and reduce errors while increasing occupational safety.

Key components inside these devices, such as encoders, motors and servo drives, ensure these vehicles are operating accurately and efficiently. Choosing the correct motion control component is highly important in the design of autonomous guided vehicles.

Satcom & UAV

Industrial robotics has also provided us with systems capable of maneuvering in aerial vehicles and space applications. Unmanned aerial vehicles (UAVs) use precise sensing and motion control systems to fly through the air, where their uses range from agriculture to surveillance applications. This requires extremely low-weight, energy-efficient components for dynamic motion control with extreme precision.

Satellites similarly make use of industrial robotic systems to achieve precise and rapid positioning movements. With power being a precious commodity in orbit, satellites rely on highly optimized and energy efficient systems to change positioning.

Interested in Industrial Robotics Solutions?

Celera Motion delivers precision components and mechatronic sub-system assemblies for advanced industrial robotics systems. To find out more about our encoders, motors, servo drives and mechatronic sub-systems, contact a member of the team today.

Robotics and autonomous systems represent an ever-evolving, high technological field of engineering covering a wide range of applications and theories, including computational architectures; human-robot interfaces; manipulation and locomotion; planning and navigation; sensing, and perception; machine-learning and adaptation; self-calibration and repair; and so on.

Autonomous mobile robots, sometimes abbreviated to AMRs but more commonly referred to by the simpler moniker of autonomous robots, are the culmination of this complex applicational intersection. But what is autonomy in the context of robotics, and what is the difference between an autonomous robot and a conventional robotics system?

What is an Autonomous Robot?

Robotics has been a mainstay of industrial settings for decades, but few of these could truly be classified as an autonomous system. Human beings have autonomy as we are capable of advanced decision-making. We can process information, draw conclusions, and carry out a host of executive functions with total independence. Autonomous robots are qualified by similar capabilities. If a robot can perceive its immediate surroundings and actuate movement/manipulation based on internal decision-making, then it can be described as truly autonomous.

It is important to differentiate truly autonomous robots from pre-programmed machines and automated actuators which typically operate via remote human control/intervention or using complex guidance systems. Robot arms on an assembly line, for example, operate on complex yet pre-programmed functions, meaning they are only equipped to carry out the same repetitive motions and cannot react to dynamic circumstances.

Key Components of Autonomous Robots

In order to carry out truly autonomous action, robotic systems must be equipped with sensory components, information-processing capabilities, and some form of actuation.

Most autonomous robots are equipped with some form of optical sensing so the machine can “see” the surrounding environment. An entire suite of photonics solutions is used to enable next-generation robotics systems to perceive critical information such as distance and orientation which acts as a crucial input for subsequent decision-making and action. For example, the Mars Curiosity Rover is equipped with multiple integrated Mastcams used to capture full-color footage of the surrounding environment with a panoramic view.

The computational aspect of autonomous robots is usually based around machine learning and artificial intelligence, using advanced algorithmic analysis to parse out data and make decisions in real-time. Such an embedded system can read visual data to determine the distance between the robot and an obstacle and to subsequently adjust course to navigate around it.

Although the sensory input and computational array collect and process data, motors are typically actuated to carry out the desired function. For example UVD robots are used to automate critical disinfection runs in clinical settings, using AMRs equipped with ultraviolet torches to sterilize surfaces. This requires careful motion tracking and compact, high-performance servos capable of actuating movement with optimal power efficiency to ensure operations can run uninterrupted for extended periods.

Interested in Autonomous Robots?

In robotics and autonomous systems, it is important to establish continuous communications between all three of these key components (sensor, processor, and actuator). At Celera Motion, we have extensive experience producing compact servo drives and systems compatible with Wi-Fi and Bluetooth modules for reporting system information. If you would like more information, contact a member of the team today.

Inductive sensors operate on the basic principle of electromagnetic induction whereby an electromotive force is induced across a conductor (target) within a changing magnetic field generated by an antenna. Inductive rotary sensors differ from electrical transformers like resolvers in that their conductive elements are based on printed circuit board (PCB) traces rather than windings. This yields numerous benefits including greater design flexibility; lower cost, size, and weight; and a true absolute digital position output. Like resolvers, inductive rotary sensors are capable of high accuracy angle position measurement in challenging environments.

Before exploring the specific use cases of inductive sensors, it is worthwhile outlining a few different types of inductive sensors in more depth.

3 Types of Inductive Sensor

  • Inductive angle encoders are angle position sensors that operate like inductive transformers comprising a flat, ring-shaped stator and a rotor with a large bore for cables, optical fibres, through-shafts, and so on. These are ideal for non-contact sensing in tough environments.
  • Inductive linear sensors measure absolute linear position based on the same basic principles as rotary sensing elements (i.e. using a target and antenna).
  • Inductive proximity sensors are a common type of inductive sensor used to detect the approach of nearby metal objects in factory automation equipment. Inductive proximity sensors use the same operating principles as inductive encoders, however rather than consisting of both a target and antenna, the inductive proximity sensor contains an antenna, with the incoming external metal object as the target.
Inductive Sensors

Zettlex Inductive Sensor

Applications of Inductive Sensors

The superior design flexibility and exceptional performance of inductive sensors makes them an ideal fit for a wide range of market segments, from medical robotics through to subsea robotics.

Satcom

Satellite communication systems are an important component within global communication networks. Network infrastructure is required to grow to meet the ever-increasing demand for data transmission. SATCOM systems include high performance Ka-, Ku- and X-band antenna pointing systems in SATCOM-on-the-move, and SATCOM-on-the-pause settings. Utilized in numerous ground vehicles, maritime ships, and aircraft, these antennas are designed in a range of sizes, for different frequencies and applications. Inductive sensors provide reliable position feedback for optimized motion control within antenna pointing systems. Designed for use in harsh environments, inductive sensors are highly immune to EMI and operate in extreme temperatures, as well as wet, and dirty settings.

Medical

Innovations in the automation of medical tasks are always advancing, equipping medical professionals with advanced tools to improve patient outcomes. High-precision inductive sensors are used as position feedback devices in a broad range of medical applications such as surgical robotics, medical imaging, and exoskeleton robotics. The common requirement is high reliability and safety in life-critical applications. In the case of surgical robotics, systems require precise, absolute position feedback from lightweight, compact inductive sensors, shaped for an exact system fit.

Subsea Robotics

Subsea robotics are essential tools deep water exploration and industry. High resolution inductive sensors are indispensable in remotely operated underwater vehicles (ROVs) comprising multiple hydraulically-actuated manipulators. With high-res outputs and complete functionality when submerged in oil, inductive sensors from Celera Motion enable complex manipulator functions in subsea ROV applications.

Interested in Celera Motion Inductive Sensors?

At Celera Motion, our flagship inductive sensor product is the new Ultra IncOder Series of inductive angle encoders. With up to 22-bits resolution, a low-profile form factor, and highly reliable non-contacting technology, our Ultra IncOderTM products have been proven in some of the harshest conditions on Earth. Looking for more information? Contact a member of the team today.

Satellite communication plays a fundamental role in our interconnected global network. Most operational satellites use positioning systems that make these communications possible. These positioning systems are located in different parts throughout the satellite system. Utilizing reliable positioning allows an immense range of data-driven applications, including budding 5G networks and Internet of Things (IoT) connectivity, to be possible.

More satellites are launched into low earth orbit (LEO), medium earth orbit (MEO), and geostationary orbit (GEO) year-over-year.  This, among other trends for satellite communications, generates pressure on designers, including increased production of LEO satellites to reduce signal latency.

Satellite Communications

Commercial satellites orbit at altitudes of 160 – 35,786 km from the earth. This exceptionally wide scale covers all three orbital ranges; LEO, MEO, and GEO. Geostationary, or geosynchronous, satellites are preferred for communications applications as they are positioned above the Van Allen radiation belt, which can prove inhospitable to sensitive electrical components. However, it takes approximately 0.22 seconds for satellites in geosynchronous orbit to relay signals, which creates a perceptible latency.

LEO satellites orbit earth at the closest altitudes, which simultaneously reduces latency and coverage. While it takes only a few GEO satellites to provide worldwide coverage, numerous interconnected LEO systems, using careful telemetric components and ground-level antenna pointing systems (APSs), are required to reach such communication levels. However, LEO networks represent an exciting frontier for low latency 5G broadband with widespread interconnectivity.

One of the primary challenges from a satellite communications design perspective is the need for automated APSs that can track the positions of LEO satellites accurately and fast. This may require a mobile solution for example, such as Satcom-on-the-Move (SOTM) APSs for air, land and sea. However, these systems are exposed to harsh atmosphere conditions including moisture, extreme temperatures, dust and several contaminants, such as oil or sand, which are a pervasive risk.

Positioning Systems for Satellite CommunicationIf Satcom companies are to take advantage of the new horizon of LEO interconnectivity, they must overcome the above-mentioned challenges – designing powerful and robust systems and solving ground issues, such as motion-induced errors in APSs mounted on marine vessels.

Positioning Systems

Due to the number of satellites being designed for orbits like LEO, APS has become an aggressive market. The ultimate decision when selecting a particular APS will depend mostly on its performance tracking and pointing a particular satellite/constellation.

Most APSs require at least two degrees of freedom (DOF) of motion. These two DOF are mainly the azimuth and elevation axis of a gimbal, performing the mechanical steering of an APS. Some APSs require a three or more DOF, depending on the frequency band and location of the terminal. An antenna dish will normally be mounted on that gimbal, to perform the above-mentioned operations. The precision obtained by the gimbal will directly affect the gain and pointing accuracy of the APS.

There are many parameters that will affect the performance of the APS, controlled by the design at a system level. One of the most important factors that will play a significant role in the overall performance of the APS is the quality and precision of the motion-related components on the mechanical steering system, especially because these are very difficult to change once the design has been completed.

APS Components from Celera Motion

Celera Motion offers a suite of high-accuracy components for reliable positioning in antenna pointing systems. The Ultra IncoderTM Series of rotary encoders are non-contact inductive angle encoders designed specifically for use in harsh environments, exceling at precise angle measurements with up to 22-bits resolution. This enables high pointing accuracies for Very Small Aperture Terminals (VSAT) with MIL-standard shock and vibration performance, providing admirable resistance to motion-induced challenges.

These low format encoders are also optimized for reliability under fluctuating temperatures. High EMI-immunity and low radiated emissions allows a strong output signal to be packed closely to other navigation equipment that can normally be sensitive to radiated emissions. This high EMI-immunity can allow a smaller footprint, tight package design – keeping all communication equipment in one location.

Inductive Sensor for Satcom

Indutive Sensor for Satcom

Celera Motion has also provided a range of positioning systems suited for lightweight, energy-efficient systems. Read this application story on satellite communications for details.

Interested in learning more about our Satcom-grade rotary encoders? Our Ultra Incoders are available in Mini (37 – 58 mm OD) and Midi (75 – 300 mm OD) sizes to suit varied end-user configurations. Contact us for more details on integrating our best-in-class rotary encoders for your satellite communications system.

[Source: World Economic Forum]

 

Fundamentally, all electric motors convert electrical energy into rotational kinetic energy by exploiting the laws of electromagnetism. But these physical rules have given rise to a variety of motor architectures, which offer very different performance characteristics. In this article, we take a look at the two most common motor designs: brushed and brushless motors.

Brushed Motors

The relatively simple brushed motor was the first type of electric motor to attain widespread use.

A brushed motor essentially consists of two parts: a stator and a rotor. The stator is made up of a stationary ring of permanent magnets. The rotor, which sits inside of the stator, consists of a ring of electromagnetic windings whose ends are connected to a commutator. The commutator is in constant contact with brushes that are fixed on opposing sides. Supplying direct current to the electromagnetic windings in the rotor induces a magnetic field, and it will naturally rotate until it aligns with the magnetic field of the stator.

To enable constant rotation of the rotor, the polarity of the electromagnetic windings must be alternated by cycling current through the different phases of the windings. This process is known as commutation. In brushed motors, DC current is supplied from the fixed brushes to the commutator. By turning on and off the current in a particular sequence, you can induce constantly rotating magnetic fields, which cause the rotor to spin.

Brushless Motors

Brushless motors do away with brushes; instead using electronics to commutate the motor. In brushless motors, an electronic circuit (example: Optical encoder or Hall-Effect sensors) senses the position of the rotor relative to the stator and supplies current through the three phase pairs of the stator windings, maintaining a 120° phase offset between each, to ensure smooth rotation and low torque ripple. Brushless motors are a comparatively recent motor design, made possible by the development of solid-state electronics in the 1960s.

Though the electronics involved in brushless motors are simple by todays’ standards, they represent a radical departure from the mechanical commutation systems found in brushed motors. This design change gives brushless motors a surprising number of advantages.

1. Quieter Motor Operation

Friction and electrical arcing between brushes and commutator plates in brushed motors produce substantial motor noise. In brushless motors, the job of commutation is carried out by an electronic circuit, resulting in much quieter operation.

2. Less Heat Production of the Motor

As well as producing sound, friction between the brushes and commutator plates in a brushed motor produces a significant amount of heat. This can be a serious problem in many applications. In brushless motors, the only friction that occurs is in the rotor bearings. This means heat production is much less of an issue in brushless motors.

3. Higher Motor Efficiency

This is a particularly important advantage of brushless motors. The sound and heat produced by a brushed motor essentially represent power losses from the device, taking energy away from the rotor itself – which would be used to drive the load. In brushless motors, the amounts of sound and heat produced are greatly reduced, resulting in significantly higher efficiency.

4. Longer Motor Life

The brushes in brushed motors are gradually worn away with use, since they are in constant contact with the commutator – it is only a matter of time until the brushes need to be replaced. Brushless motors do not face this problem, which drastically reduces maintenance requirements, and enables a range of applications where brush replacement would be impractical, such as in outer space satcom equipment.

5. Better Power-to-Weight Ratio of a Motor

Fewer mechanical components means brushless motors have lower mass than brushed motors. The result: brushless motors offer a better power-to-weight and torque-to-weight ratio than brushed motors.

Direct Drive Frameless Brushless Motors

All of these advantages mean that, aside from a few legacy uses, brushless motors reign supreme for present-day applications. Contact a member of the Celera Motion team to learn more about our Applimotion range of direct drive brushless motors.