Special Coverage

Converting from Hydraulic Cylinders to Electric Actuators
Automating Optimization and Design Tasks Across Disciplines
Vibration Tables Shake Up Aerospace and Car Testing
Supercomputer Cooling System Uses Refrigerant to Replace Water
Computer Chips Calculate and Store in an Integrated Unit
Electron-to-Photon Communication for Quantum Computing
Mechanoresponsive Healing Polymers
Variable Permeability Magnetometer Systems and Methods for Aerospace Applications
Evaluation Standard for Robotic Research

Scanning Performance of Air Bearing Equipped Precision Motion Systems

Scanning is a common technique in applications ranging from high-resolution microscopy to industrial material processing. Scanning involves moving either a workpiece or an optic at a constant velocity while a reading or writing operation takes place. Air bearings are used for both purposes, especially when high precision and reliability are vital. While the physical act of writing an image or capturing an image differ by application and industry, all such applications share a common requirement — maintaining a constant velocity.

Posted in: Articles, Motion Control, Imaging and visualization, Automation, Bearings, Reliability

Four Ways to improve Production by Understanding the Physics of Servos

There is always a need to increase production in automation applications. Sometimes achieving improvements requires breaking the process down to its fundamental basics. The science behind the technology of servo-based motion control systems should be considered when attempting to eliminate inefficiencies. Four fundamentals to examine are inertia, resonance, vibration suppression, and regeneration.

Posted in: Articles, Motion Control, Finite element analysis, Electronic control systems, Automation, Productivity

Converting from Hydraulic Cylinders to Electric Actuators

Hydraulics are rugged and deliver a low cost per unit of force, but electric rod actuators have attained higher force capacities while becoming more flexible, precise, and reliable.

Advances in motion control technology have prompted a new debate — do hydraulic cylinders or electric linear actuators offer the best solution for a linear motion application? Hydraulic cylinders provide high force at an affordable cost. Hydraulics are rugged, relatively simple to deploy, and deliver a low cost per unit of force. However, electric rod actuators (electric cylinders), particularly those with roller screws, have attained increasingly higher force capacities while becoming more flexible, precise, and reliable.

Posted in: Articles, Motion Control, Electrical systems, Flight control actuators, Hydraulic control, Reliability

The Basics of Encoder Selection

Many small motor applications, such as robotics, industrial equipment, and consumer products, employ digital incremental encoders for feedback sensing. Encoder selection is therefore an important part of the system design process. Choosing the best encoder for the job requires knowledge of the most important encoder properties as well as the application’s control requirements.

Posted in: Articles, Motion Control, Electronic control systems, Integrated circuits, Supplier assessment

Servo Couplings for High-Tech Systems

Proper coupling ensures a design will meet performance requirements and have a long, trouble-free life.

Couplings are a critical part of system performance in high-tech applications, yet they are often one of the last components to be specified. Selecting the proper coupling ensures the equipment will meet performance requirements and have a long, trouble-free life. Poor coupling selection can lead to high maintenance costs, frequent downtime, and imprecise positioning.

Posted in: Articles, Joining & Assembly, Motion Control, Power Transmission, Sensors and actuators, Materials properties, Fittings, Parts

Metallic Glass Shatters Gear Limitations

Gears play an essential role in precision robotics, and they can become a limiting factor when the robots must perform in space missions. In particular, the extreme temperatures of deep space pose numerous problems for successful gear operation. At NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, CA, technologist Douglas Hofmann and his collaborators aim to bypass the limitations of existing steel gears by creating gears from bulk metallic glass (BMG).

Posted in: Articles, Aerospace, Manufacturing & Prototyping, Metals, Mechanical Components, Motion Control, Motors & Drives, Power Transmission, Robotics, Robotics, Alloys, Glass, Gears, Durability, Spacecraft

Adding SCADA to a Hydraulic Power Unit

With an increased focus on plant productivity and equipment reliability, Supervisory Control and Data Acquisition (SCADA) systems have become vital tools to reduce downtime while increasing asset reliability in hydraulic systems. A SCADA system is a computer system that essentially gathers and analyzes real-time data.

Posted in: Articles, Fluid Handling, Motion Control, Computer software and hardware, Hydraulic and pneumatic hybrid power, Productivity, Hydraulic control

The Basics of Encoder Selection

Positioning: Resolution and Accuracy

An application’s required positioning resolution dictates the choice of encoder resolution. A well-tuned system can maintain the position within one encoder state (quadcount). Therefore, the encoder resolution in quadcounts (states) should at least correspond to the maximum permissible positioning error. Depending on the response time of the system, a higher encoder resolution should be chosen for the controller to detect deviations faster and counteract quicker.

Posted in: Articles, Motion Control, Calibration, Navigation and guidance systems, Reliability

Choosing Stepper- or Servo-Driven Actuators to Replace Air Cylinders

Pneumatic (air) cylinders are widely used in industrial automation due to their low per-axis cost and high-speed/force capabilities. They have a long history of being popular workhorses in the automation industry. However, there are many reasons to use electric actuators in place of air cylinders: reduced machine downtime, reduced energy consumption, increased precision, and increased speed. In addition, electric actuators can be powered by servo or stepper motors, in conjunction with a control device, to provide linear motion.

Advantages of Electric Linear Actuators

Reduced downtime. Electric linear actuators (whether screw- or belt-driven) are very low-maintenance. Regreasing may be the only regular maintenance necessary, and many screw-driven models are lubricated for the life of the actuator.

Posted in: Articles, Aerospace, Motion Control, Sensors and actuators, Electric motors, Durability

Precision Robotics and Automation: Hexapods Advance Production Processes

Hexapods — six-legged parallel-kinematic machines — are quickly gaining ground in a broad range of industrial automation applications after “learning” how to directly communicate with PLC or CNC controllers via Fieldbus interfaces. As far as the semiconductor and electronics industry, automobile industry, and precision assembly are concerned, many production processes have become inconceivable without them. Today, the six-axis positioning systems are available with load capacity from 2 kg to 2000 kg, and travel from 10 to hundreds of millimeters while maintaining submicron precision. Hexapods are used for aligning the smallest optical components in the latest silicon photonics production processes, for controlling automated labeling machines, and positioning entire body parts for automotive production. The intrinsic hexapod features contribute to a wealth of new possibilities in robotics.

Posted in: Articles, Motion Control, Automation, Robotics, Optics, Kinematics, Automation, Production, Robotics

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