Practical understanding of complex mechatronic systems
This spring, Mikrocentrum will start a new course for higher educated engineers. During the five-day courses, Sven Hol, Ph.D., will discuss the theoretical aspects of the various disciplines within the field of mechatronics, after which the participants will familiarise themselves with modelling, simulating and controlling mechatronic systems.
Article as appeared in Mikroniek issue 2 - 2017
Even though the Applied Mechatronics course is suitable for every branch of the industry, it focuses mainly on those manufacturing processes that require increased dynamics and precision. This counts for the actual manufacturing of (parts of) the product, but also for assembly, pick & place, and handling systems.
Need for mechatronic know-how
Mechatronics is an engineering discipline that combines mechanics, electronics, control engineering and computer science. This combination prevents creating suboptimal solutions to a control problem in a single discipline. Factors such as thermal management, friction, stability and performance are taken into account as well.
An increasing number of companies eventually has to deal with different disciplines through their original discipline (particularly in the case of mechanical/precision engineering). Often the knowledge of and experience in these other disciplines are lacking. Moreover, there seems to be much to gain from the integration of the various disciplines. Sven Hol and Mikrocentrum noticed that a practically focused, high-level course revolving around these aspects was much needed. In consultation with Mikrocentrum, which wanted to include a practical aspect, Sven Hol developed the current course.
Applied Mechatronics course target group
The training is aimed at people in the industry who are already familiar with mechatronics, such as system architects, mechatronic designers, machine engineers, electrical engineers, software and firmware developers. The training assumes a higher education level (HBO+ or university) and at least two years of work experience with mechatronics. It has been constructed in such a way that a specialist in one discipline can still understand the theory and practice of the other disciplines. After the course, he/she will be able to combine these less familiar disciplines with his/her own know-how.
Mikrocentrum’s intended audience for the course are companies that deal with mechatronic systems for which they require precise and controlled motion and strive for increased speed and productivity. Next to high-tech companies, these can be manufacturers of office equipment (e.g. copiers), packaging, sorting or assembly machines, and medical equipment as well. But also their suppliers seem to feel the need for more knowledge, in order to understand what their customers are working on.
The course is also relevant when it comes to heavy machinery (such as (road) construction equipment, agricultural machinery, recycling systems or internal transportation). A higher positioning accuracy often is not relevant here. But these companies often do aim for higher productivity, lower environmental taxes, lower energy consumption and data recording. Mechatronics can play a significant part in attaining those objectives.
Set-up of the Applied Mechatronics course
The course lasts five days (Figure 1): three days for mostly theory, modelling and simulating, followed by two days of practice. During the first three days, the various disciplines will be discussed including their mathematical models. These will eventually be merged in one complete model. The objective of the theoretical part is making the model for a demo system, which will then be tested during the two practical days and used for calculations and measurement.
On the first day, mostly mechanics will be discussed. Participants will learn the meaning of mechanical quantities and of mass, stiffness and damping and how to put them into models. Sensors and actuators are the topic of the second day. A closer look will be taken at different kinds of drives, sensors and amplifiers and how these match the intended application and performance. The participants will make models in the frequency domain (where they will learn how to interpret and deal with resonances, among other artifacts) and in the time domain (how a process develops through time).
On the third day, PID control, feedback and feedforward will be discussed. The participants will make and implement their own mechanism and test its validity. The focus will also be on the response, sensitivity and stability (margin) of the controller and the performance of the complete system. With the various building blocks the participants will finally build one complete model. The modelling process will be realised with mathematical computing tools, MatLab and Simulink. The models and tools are such that newcomers can use them as well. Lastly, practical implementation and fine-tuning will be discussed.
On the fourth and fifth day, both the theory and the constructed system will be assessed by means of a demo system that Sven Hol has developed himself and built with the aid of Mikrocentum and a number or partners.
Participants can work on a demo system, i.e. a single-axis linear system. Multiple axes will obviously make a system more complex; however, every axis can be modelled in the same way. In order for the system to work properly, a coupled control strategy is then needed, for instance, a master-slave system with a multiple-axis controller.
The mechanism consists of a guidance track with two so-called ‘stages’ that can move independently. Behind, there is an array of magnets, which creates a linear motor. The stages contain a small three-phase coil system and when activated, the stages can move along the magnet array. A linear encoder is placed on the guidance track in order to determine the position of the stages accurately.
The two stages are connected by a fixed rod, which can be placed in several positions between two leaf springs. In this way, different degrees of stiffness (from a very stiff transfer to a very weak one) can be accomplished. The stiffness between the actuated stage and the measurement stage influences the performance and stability of the entire system. During the practical part, the participants will experience how the demo system reacts to changes in stiffness and motor control. In this way, a very realistic experiment for the participants will lead to a solid understanding of complex mechatronic systems.
About the Applied Mechatronics course teacher
Sven Hol studied Mechanical and Automation Engineering at the University of Twente, the Netherlands, and received his Ph.D. in Mechatronic Design at the Eindhoven University of Technology, the Netherlands. At ASML he held several functions, including electro-mechanical designer, customer service manager at ASML Japan, and researcher. Currently, he is a mechatronic architect at ASML and works as an independent consultant helping other companies with mechatronic challenges.