Performing Flexible Control on Low-Cost Microcontrollers Using a Minimal Real-Time Kernel

Abstract

Abstract-In recent years, approaches to control performance and resource optimization for embedded control systems have been receiving increased attention. Most of them focus on theory, whereas practical aspects are omitted. Theoretical advances demand flexible real-time kernel support for multitasking and preemption, thus requiring more sophisticated and expensive software/hardware solutions. On the other hand, embedded control systems often have cost constraints related with mass production and strong industrial competition, thus demanding low-cost solutions.In this paper, it is shown that these conflicting demands can be softened and that a compromise solution can be reached. We advocate that recent research results on optimal resource management for control tasks can be implemented on simple multitasking preemptive real-time kernels targeting low-cost microprocessors, which can be easily built in-house and tailored to actual application needs. The experimental evaluation shows that significant control performance improvement can be achieved without increasing hardware costs.

A loosely coupled architecture for networked control systems

“…There it is proposed that the rate should be proportional to the quadratic error and to a constant given to each process, so that more important processes still somehow have a higher priority. A similar approach had been proposed before (see [7] and in references therein). These approaches cause slight oscillations.…”

Design of an Embedded Control System Laboratory Experiment

“…As a hardware platform, a microcontrollerbased architecture was selected because embedded systems are typically implemented using this type of hardware. Note, however, that too small microcontrollers may not be powerful enough for running an RTOS, as discussed in [22]. Among the several possibilities available on the market [23], it was decided to adopt the Flex board [24].…”

PID Control of a Lab Scale Single-Rotor Helicopter System using a Multicore Microcontroller

“…The Concerto family of from TI Inc. [5] and the latest members of the SPC56 family from ST Inc. [6] are examples of multiprocessing systems for embedded real-time applications. Moreover, many researchers started to realize that using these multiprocessing techniques and systems would be beneficial even by using multitasking within a single processor [7] [8], by using multiple independent MCUs [9] [10], by using multicore platforms [4] [11] [12] or by customizing their own multiprocessing systems. Currently, traditional MCU technologies are migrating to multiprocessing systems as multicore MCUs are more and more becoming available.…”