Preliminary design and sizing mechatronic systems: context#
In the context of rapid technological changes and increasingly complex industrial organizations, the task of developing a new system from scratch presents a substantial challenge. The preliminary design and sizing phase represents one of the most crucial steps in the overall product development process, where the core features and performance of a system are first defined. This early stage is critical, as it establishes the foundation for key system characteristics and directly influences the final performance, feasibility, and cost of the product.
The preliminary design and sizing phase necessitates a careful balancing act between comprehensive analysis and efficient execution. On one hand, thorough trade-off studies must be conducted to evaluate alternative architectures and determine the most promising candidate. On the other hand, the process must be conducted within a reasonable timeframe to allow sufficient opportunity for subsequent, more detailed design and integration steps. The effectiveness of this stage is highly dependent on employing comprehensive methods and modelling techniques that provide a deep understanding of the behaviour of different design options, address the inherent complexity of systems, and enable informed decision-making. In the context of global decarbonization efforts, there is a growing emphasis on developing electrified technologies that reduce environmental impact while enhancing system efficiency. This shift towards electrification has led to a significant rise in the adoption of mechatronic systems, which integrate mechanical, electrical, and control components to create optimized and sustainable solutions.
For example, in the design of an electric vehicle (EV) powertrain system, several key decisions must be made during the preliminary design phase. These decisions include selecting the type of motor, determining the power requirements, and specifying the battery capacity. The choice between different motor technologies, such as permanent magnet synchronous motors or induction motors, involves evaluating a range of factors, including efficiency, cost, cooling requirements, and availability of materials. The sizing of the battery is equally complex, as it requires balancing energy storage capacity to provide sufficient range while minimizing overall weight and cost. These choices significantly affect not only the overall performance and efficiency of the EV but also the user experience and product lifecycle costs.
Similarly, in aerospace applications, the preliminary design of an electro-mechanical actuation system for aircraft control surfaces requires careful evaluation of various actuation technologies. Engineers must choose between traditional hydraulic actuation and modern electro-mechanical solutions, each offering distinct advantages and limitations. Electro-mechanical actuators (EMAs) present benefits such as reduced weight and improved maintainability, yet they require meticulous consideration of power consumption, redundancy, and thermal management. By conducting a comprehensive trade-off analysis early in the design phase, it becomes possible to select the optimal configuration that complies with stringent regulatory requirements while meeting performance targets.
Preliminary sizing is an equally critical aspect of this early phase. It involves estimating the dimensions, weights, and performance characteristics of the system components to ensure the overall feasibility of the design. For instance, in the development of an unmanned aerial vehicle (UAV), the sizing of components such as propellers, motors, and battery capacity plays a pivotal role in ensuring that the UAV can carry the intended payload and achieve the desired flight duration or range. The preliminary sizing process employs models mainly based on analytical equations or simulations as well as empirical data to establish estimates for each component, which then guide the subsequent detailed design phase. Improper sizing at this stage can lead to a design that either fails to meet the performance requirements or is non-optimal in terms of cost or mass.
The objective of this course is to provide the necessary methodology for the preliminary design and sizing of mechatronic systems, particularly focusing on addressing the challenges of designing novel systems for which no established design procedure can simply be found in a textbook.