Motion Control

Six-Legged Robots Move Faster with Bipod Gate

Researchers have discovered a faster and more efficient gait, never observed in nature, for six-legged robots walking on flat ground. Bio-inspired gaits, which are less efficient for robots, are used by real insects because they have adhesive pads to walk in three dimensions. (Credit: EPFL/Alain Herzog)

Researchers in Lausanne, Switzerland have determined that a bipod gait is the fastest and most efficient way for six-legged robots to move on flat ground, provided they don’t have the adhesive pads used by insects to climb walls and ceilings. This suggests designers of insect-inspired robots should make a break with the nature-inspired tripod-gait paradigm.

Posted in: News, Motion Control, Robotics

Evaluation Standard for Robotic Research

Universal benchmarks can standardize the measurement of robotic manipulation tasks.

The Yale-CMU-Berkeley (YCB) Object and Model Set provides universal benchmarks for labs specializing in robotic manipulation and prosthetics. About two years ago, Aaron Dollar, an associate professor of mechanical engineering and materials science at Yale University, came up with the benchmark idea to bring a level of specificity and universality to manipulation tasks in robotics research. He enlisted the help of two former colleagues in the robotics community, Dr. Siddhartha Srinivasa from Carnegie-Mellon University and Dr. Pieter Abbeel of the University of California, Berkeley.

Posted in: Briefs, Motion Control, Automation, Kinematics, Research and development, Robotics, Quality standards, Biomechanics

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

Control Scheme Improves Motor Operation and Interaction

A team of researchers from the Polytechnic University of Bari, Italy, is working to improve how industrial electric drives operate. They propose a new control scheme that will not only improve motor operation, but also how the motor interacts with other systems.

Posted in: News, Motion Control, Motors & Drives, Mathematical/Scientific Software, Simulation Software

Tool Helps Design Soft Robots That Can Bend and Twist

Designing a soft robot to move organically — to bend like a finger or twist like a wrist — has always been a process of trial and error. Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering have developed a method to automatically design soft actuators based on the desired movement.

Posted in: News, Implants & Prosthetics, Motion Control, Robotics, Computer-Aided Design (CAD), Software

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

How To Substantially Reduce Encoder Cost While Gaining Functionality With Multi-Turn Rotary Position Sensors

Many applications require rotation counters that can measure angles greater than 360º. However the low-cost 10-turn potentiometers most design engineers are familiar with can’t always meet user requirements for resolution and reliability. As an alternative, optical absolute encoders are too expensive for many applications. These solutions require a continuous power supply or they will lose count when power is restored. Also, geared technology/rotation counters are subject to significant wear.

Posted in: White Papers, Motion Control, Automation, Robotics, Data Acquisition, Sensors

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