This simple system can be used as a teaching tool. The project aims to implement PI, PID, and SMC control of a DC servo system, both as a simulation and real-world measurement. In the literature, some hybrid solutions are reported to overcome this problem. SMC is usually referred to as an interesting theory, as the mathematical model itself works very well on a theoretical level, but implementation can be a significant challenge. Because of the switching behaviour of sliding mode control, it is commonly used in power electronics. However, when the system has a variable load, rather than nominal ones, using a PI or PID controller does not result in a fast and stable output voltage response.Īnother possible method is sliding mode control (SMC). PI and PID control usually satisfies the most common requirements. Both speed and position control are possible with a wide range of controllers, with the most common control method being PI or PID. Permanent-magnet brushed DC motors, and servo drives are widespread in industry and DIY home projects, ranging from low-power versions to vehicle drive systems.

However, the more robust but mathematically far more challenging sliding mode control is usually introduced later in graduate studies. Conventional PID control is part of the control engineering curriculum for bachelor-level courses. The ability to experiment with the effects of different control strategies on real-world processes is even more helpful. Simulating control systems helps students understand control methods better than written textbook examples. LabVIEW code can be compiled to run on computers, (soft) real-time targets, and FPGAs (hard real-time targets), so students can easily and quickly step up to real industrial measurement and control problems without the need to learn new programming environments.

Then a myRIO Student Embedded Device is used to control a real servo system.

The first didactic step is a simulation with the Control Design and Simulation, as well as MathScript RT Modules. However, the mathematical background of sliding mode control is difficult compared to conventional PID control the SMC implementation for practical uses can be quite simple, as the presented example demonstrates. The graphical “coding” can help novice users to see through their algorithms. Both programming environments and the connection to NI hardware are relatively easy to use, therefore, ideal for education. The control of an actual system with LabVIEW and NI hardware provides an efficient implementation platform, using both LabVIEW’s graphical programming and the text-based m-file language MathScript RT.

The main contribution of this paper is to present the efficiency of LabVIEW in simulating and controlling a servo system with conventional methods (PI and PID control), as well as sliding mode control (SMC).

Encoder pid control in labview