PID Turntable

Precise control of rotational systems is crucial in many applications, from robotics to industrial automation. This project addressed the challenge of creating a turntable system that could accurately follow a complex, user-defined waveform with minimal tracking error.

The primary objective was to design and implement a control system that could minimize the error between the desired waveform and the actual turntable position, while ensuring stability and responsiveness. The project explored both analog and digital control implementations to understand their relative merits.

Analog PID Control Circuit

Control Objectives

• Precise angular position tracking for complex waveforms
• Minimized steady-state error and transient response time
• System stability across varying operating conditions
• Analog vs. digital control implementation comparison

System Requirements

• Fast response to step inputs with minimal overshoot
• Accurate tracking of sinusoidal and triangular reference signals
• Performance consistency despite system parameter variations
• Smooth operation without excessive control effort

Analog Implementation

• Operational amplifiers for PID computation
• Resistors and capacitors for gain setting
• Potentiometers for tuning parameters
• Turntable with DC motor and encoder
• Wave generator for reference signals
• Oscilloscope for signal monitoring

Digital Implementation

• LabVIEW programming environment
• Data Acquisition (DAQ) system
• Digital signal processing algorithms
• Real-time control loop implementation
• Computer-based parameter adjustment
• Control algorithms capability

Analog PID Controller

Operational amplifier-based implementation providing continuous operation and faster response times without digital sampling delays. Smoother control action avoids quantization errors, ideal for high-speed applications requiring immediate response.

Digital PID Controller

LabVIEW implementation with real-time control and data acquisition through DAQ systems. Digital approach enables control algorithms and parameter adjustment through software.

Performance Trade-offs

Analog implementation offers simplicity and continuous operation with no sampling delays. Digital implementation provides flexibility for complex algorithms and easier parameter tuning. Both approaches achieved comparable position tracking accuracy for the turntable system.

Control

• Feed-forward control for disturbance rejection
• Adaptive control algorithms
• Velocity and acceleration feedforward

Hardware Optimization

• Higher resolution encoder for improved accuracy
• Motor with reduced backlash
• Improved analog circuit board design

Microcontroller Implementation

• Embedded system for standalone operation
• Real-time parameter tuning interface
• Data logging and analysis capabilities