Actuation Systems

Precision FOC Actuator

A field-oriented-control actuator combining precision electromechanical actuation, optical angular measurement, FPGA-based control, and calibration into a single integrated system.

Precision FOC actuator
Purchasing

Interested in purchasing?

If you are interested in purchasing a precision FOC actuator, or would like to discuss a different actuator size, force range, or control configuration, contact us to discuss the requirements.

Contact Us
Precision Actuation

An actuator designed as a measurement and control system

Conventional stepper motors often operate as open-loop devices, with position inferred from commanded motion. This actuator combines a hybrid stepper motor with optical angular measurement and closed-loop field-oriented control.

The system continuously measures motor position and phase current while the FPGA executes the control loop. This architecture turns the actuator into a closed-loop precision motion and force-control platform rather than a conventional open-loop stepper.

System Architecture

Actuation, measurement, and control in one system

The actuator integrates the motor, optical sensing, control electronics, and computational infrastructure required for closed-loop precision control.

Electromechanical Actuation

A hybrid stepper motor operates as a two-phase synchronous machine under field-oriented control. The control system directly regulates the torque-producing current.

Optical Angular Measurement

An optical encoder provides shaft-angle information directly to the control system. The sensing system combines a characterized optical code disk with a precision analog front end.

FPGA Control

FPGA logic executes field-oriented control, position regulation, current regulation, coordinate transforms, calibration lookup, and PWM generation through a deterministic hardware datapath.

Control

Multiple control domains

The actuator supports multiple control domains through the same underlying electromechanical and computational architecture.

Position Closed-loop angular positioning using optical encoder feedback.
Precision Torque Direct regulation of torque-producing motor current for controlled electromechanical output.
Constant Speed Closed-loop velocity regulation for applications requiring controlled rotational speed.
Impedance Programmable mechanical response that allows the actuator to behave as a compliant or resistive element during interaction.
Specifications

Actuator specifications

These specifications describe the current actuator architecture and established operating characteristics.

Motor type Hybrid stepper
Control architecture Field-oriented control
Position feedback Optical encoder
Control implementation FPGA hardware
Control loop 80 kHz
Control modes Position, precision torque, constant speed, impedance
Force control Micro-newton level
Calibration

Calibration integrated into the actuator architecture

The actuator combines optical position measurement with FPGA control and calibration data. The control system uses the measured behavior of the actuator as part of its operating configuration.

Encoder Calibration The optical encoder provides calibrated angular feedback for closed-loop motion control.
Motor Characterization The control architecture supports characterization of repeatable motor behavior and electromechanical response.
Application-Specific Calibration Calibration parameters integrate with the control architecture to match the actuator to its mechanical and application requirements.
Configuration

Standard actuators and configured systems

The actuator platform supports different mechanical sizes, force ranges, sensing configurations, and control requirements. Standard configurations provide a starting point for applications that need precision electromechanical actuation.

Customers can also combine actuator geometry, sensing, control electronics, computation, and calibration around a specific application.

If you have a specific actuator application or configuration in mind, contact us to discuss the requirements.