QUBE Servo 2 Teaching Experiment Platform

QUBE Servo 2 Teaching Experiment Platform

Introduction: Positioning and Selection Challenges of Teaching Servo Experiment Platform

In undergraduate courses of mechatronics and control engineering, hands-on experiments are a key component in helping students understand abstract control theory. The ideal teaching experimental equipment should have the following characteristics: safety and reliability, measurable and controllable parameters, modular design, seamless integration with mainstream development environments, and controllable costs.

Quanser QUBE Servo 2 is a self-contained, low-cost servo motor experimental platform designed specifically for this requirement. It integrates a DC motor, photoelectric encoder, built-in current sensor, power amplifier, and data acquisition interface, and is equipped with two additional modules: inertia disk and swing rod. Unlike traditional large rotary servo test benches, QUBE Servo 2 is compact in size (about the size of a fist), yet retains complete closed-loop control teaching functions.

For laboratory managers or course leaders, the following practical issues may arise when deploying the equipment:

Confusion in Interface Selection: Differences and Applicable Scenarios between USB Version and Embedded Version.

Software configuration failure: Common errors during MATLAB/Simulink or LabVIEW driver installation and real-time control environment setup.

Hardware expansion requirements: How to independently design 3D printing modules and integrate them with the system.

Alignment of teaching resources: How to match experimental content with classic textbook chapters such as Nise's "Control Systems Engineering".

This article will provide a complete technical reference for university teachers and laboratory technicians from six dimensions: technical architecture, detailed explanation of dual interface mode, software configuration process, common troubleshooting, modular experimental design, and integration of course resources.

System architecture and working principle

2.1 Core Components

QUBE Servo 2 is a highly integrated experimental system that mainly includes the following hardware:

DC motor: Brushed DC motor, used as the actuator.

Optoelectronic encoder: installed on the motor shaft, outputs orthogonal encoded signals, and can simultaneously measure the position (angle) and speed of the rotor (by differentiating the positions).

Built in current sensor: Real time monitoring of armature current, providing feedback for torque control and current loop experiments.

Integrated power amplifier: converts control signals (PWM or analog voltage) into the power required to drive the motor.

QFLEX 2 computing interface: The second-generation interface technology developed by Quanser, responsible for data acquisition, signal conditioning, and communication with the upper computer.

Additional modules: Inertial disk (increasing rotational inertia) and pendulum rod (forming a first-order inverted pendulum system), hot swappable through quick connection interface.

2.2 Brief description of working principle

The upper computer (PC or microcontroller) sends control voltage commands (usually ± 5V or PWM duty cycle) through the QFLEX 2 interface. The built-in amplifier converts instructions into motor drive voltage. The encoder provides real-time feedback on the rotor position, while the current sensor provides feedback on the armature current. These feedback signals are collected by QFLEX 2 and sent back to the controller, forming a closed loop.

The uniqueness of this system lies in the fact that the control algorithm can run on multiple platforms:

Run MATLAB/Simulink Real Time or LabVIEW on a PC (via USB connection).

Embedded microcontrollers (such as NI myRIO, Arduino, Raspberry Pi) are directly controlled through SPI interfaces.

2.3 Engineering value of three color LED indicator lights

There is a user controllable three color LED light strip on the front of the device. In practical teaching, it can be programmed to be used as:

System status indication: Green indicates normal position tracking, red indicates over limit or alarm.

Visualization of control performance: Brightness or color changes with error (for example, the larger the error, the redder it becomes), helping students intuitively feel the control effect.

Power or enable indication: To avoid students misjudging the system as "crashing" when the motor is not enabled.

Although this detail may be small, it is very practical in teaching demonstrations and can reduce students' reliance on the command line or oscilloscope.

Dual interface mode detailed explanation: USB version vs. embedded version

QUBE Servo 2 offers two interchangeable panels: USB interface panel and embedded interface panel. Users can choose one panel at the time of purchase or purchase another panel separately as a backup. This design allows the same hardware to serve both PC based graphical courses and low-level embedded programming teaching.

3.1 QUBE Servo 2 USB Experimental Edition

Interface: Standard USB 2.0 connection (Type-B).

Supporting software:

For MATLAB/Simulink users: Quanser QUARC real-time control software package needs to be installed, which provides Simulink module library and can directly compile models into real-time executable programs.