Eccentricity between the encoder disc center and the axis of rotation produces a once-per-revolution sinusoidal position error. The magnitude is directly calculable from eccentricity and scale radius. Two-readhead averaging and mechanical hub design are the primary mitigation strategies.
Rotary Encoder Eccentricity Error: Causes, Magnitude, and Compensation Methods Read More »
Slip rings enable continuous electrical transmission in industrial rotating equipment — cranes, centrifuges, cable reels, and packaging lines. Each application imposes distinct power, data, and environmental requirements on the slip ring assembly. This article maps application constraints to the correct slip ring architecture.
Industrial Slip Ring Applications: Cranes, Centrifuges, and Packaging Machinery Read More »
Interferential optical encoders achieve nanometer-level position resolution using diffraction gratings and coherent laser sources. The operating principle — VCSEL illumination of a grating, Talbot plane selection, and differential photodetection — enables interpolation factors that conventional LED-based encoders cannot match.
EtherCAT and CANopen fieldbus networks define how servo drives and encoders communicate with motion controllers. The encoder’s position data must be synchronized with the network’s communication cycle to ensure that the control loop operates on consistent, time-stamped position values. This article covers the communication architecture, timing requirements, and encoder interface options for EtherCAT and CANopen servo networks.
Encoder Position Feedback for EtherCAT and CANopen Servo Networks Read More »
Robotic joint encoders operate in constrained envelopes with simultaneous demands for absolute position, high resolution, low profile, contamination resistance, and no homing requirement. The selection between optical, inductive, and capacitive technologies for robot joints is driven by how each handles these competing constraints.
Rotary encoders convert angular position into electrical signals through optical scanning, electromagnetic induction, or capacitive field modulation. Understanding the physics of each sensing method — and the signal processing chain that follows — is the foundation for selecting, installing, and troubleshooting rotary position feedback systems.
How Rotary Encoders Work: Complete Operating Principles Reference Read More »
Single-ended encoder signals degrade over cable lengths that are entirely acceptable for differential pairs. When cable length and data rate require transmission line modeling, unterminated lines produce reflections that corrupt position data. This article provides the engineering criteria for determining when termination is required and how to implement it for RS-422 encoder outputs.
Differential Signaling and Transmission Line Termination in Servo Encoder Cables Read More »
CT scanner gantries rotate continuously at speeds up to 300 rpm while transferring kilowatts of power to the X-ray tube, transmitting gigabits of image data, and providing position feedback from an integrated encoder. Slip ring and gantry subsystems for CT applications must address all three functions simultaneously within a compact, high-reliability rotating assembly.
Slip Rings for CT Scanner Gantries: Power, Data, and Subsystem Integration Read More »
Wind turbine pitch control systems transmit electrical power and control data from the nacelle to the rotating hub through slip rings. The electrical and mechanical requirements of pitch slip rings — operating temperature range, current capacity, data protocol support, and service life — are significantly more demanding than standard industrial slip ring applications.
Slip Rings in Wind Turbines: Pitch Control and Data Transmission Requirements Read More »
Pitch control slip rings are highly specialized rotary joints engineered to transmit critical power and data signals under some of the most demanding environmental conditions on Earth.
The Critical Role of Pitch Control Slip Rings in Wind Energy Read More »