Design and Implementation of a Discrete-Time Proportional Integral (PI) Controller for the Temperature Control of a...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Control Systems

Background:

• Contact Heat Evoked Potentials (CHEPs) are vital for studying human pain activation.
• Accurate thermal stimulation is crucial for reliable CHEP signal recording.
• Existing CHEP stimulators can be costly and lack precise temperature control.

Purpose of the Study:

• To design and evaluate a novel digital proportional integral (PI) controller for a custom-made, cost-effective CHEP stimulator.
• To assess the suitability of an electric heating pad as a thermode for CHEP generation.
• To improve temperature regulation accuracy and stability in CHEP stimulation.

Main Methods:

• A digital PI controller was designed using an Arduino microcontroller.
• System identification was employed to determine the heating system's transfer function.
• Root locus technique was used for controller parameter design.
• The controller's performance was compared against conventional PI controllers and anti-windup models.

Main Results:

• The proposed PI controller demonstrated superior performance in tracking reference temperatures.
• The controller effectively rejected output disturbances, maintaining set temperatures.
• The novel design successfully circumvented the integrator windup problem.
• Performance was found to be superior to conventional PI controllers and existing anti-windup models.

Conclusions:

• The developed Arduino-based PI controller is suitable for cost-effective CHEP stimulators.
• The controller offers enhanced accuracy and stability for thermal stimulation in pain research.
• This approach provides a viable, efficient alternative for CHEP signal generation and analysis.