Understanding scientific and mathematical knowledge and practices, as well as technological and engineering practices, has become a priority for national education programs across the world [
1]. STEAM (Science, Technology, Engineering, Art, Mathematics) has recently become a standard part of higher education internationally, with many universities adapting their curriculum to integrate it [
2]. STEAM is the evolution of STEM (Science, Technology, Engineering, Mathematics), which was first introduced by the US National Science Foundation (NSF) in the 1990’s [
3]. STEM was initially developed to address the ongoing low performance of students from the Western world in mathematics and science in international assessments and to encourage students to pursue careers in these fields [
3]. In 2010, Bybee called for quality science education that includes technology and engineering:
"A true STEM education should increase students’ understanding of how things work and improve their use of technologies. ...Engineering is directly involved in problem solving and innovation, two themes with high priorities on every nation’s agenda ...the creation of high-quality, integrated instruction and materials, as well as the placement of problems associated with grand challenges of society at the centre of study". The extension of STEM to STEAM was first proposed in 2013 [
5]. As the name STEAM suggests, there is a crucial focus on encouraging students to think in a broader perspective than that of each individual subject [
6]. STEAM has been shown to improve conceptual and deep understanding of the subjects covered. Kang in 2019 conducted a literature review of six studies, which included analysing 256 papers from schools that provide STEAM education, and the results demonstrated that there is a positive and immediate effect on the student’s conceptual understanding. The methods of STEAM education are now widely used and applied at all levels of education, including higher education.
1.1. What Is Engineering Mathematics?
Engineering mathematics has two distinct but interconnected facets. On one hand, it serves as the foundation for engineering programs, typically taught by mathematicians. On the other hand, mathematics is an integral component of engineering science, providing the tools and framework for understanding and solving complex problems [
8]. Over the past decade, advancements in technology have significantly impacted the field. New algorithms and methods have emerged to help engineers analyse large databases, build predictive models, and solve optimisation problems [
9]. The increasing power of computers has enabled the application of complex numerical methods and simulation techniques, supporting engineers in modelling and understanding intricate physical phenomena such as fluid dynamics, structural analysis, and electromagnetic design [
10,
11,
12]. While still in its early stages, quantum computing offers immense potential to further revolutionise engineering mathematics [
13,
14]. We can expect breakthroughs in complex optimisation problems and simulations, potentially influencing engineering design and research [
15]. These innovations and methods empower engineers to work more efficiently on technical challenges and open new opportunities for developing and applying technology.
Engineering students’ training in mathematics is a top priority. The field relies heavily on mathematical principles, with foundational subjects like calculus, differential equations, linear algebra, and statistics being crucial for understanding and solving engineering problems. A robust mathematical background equips engineers with critical thinking and problem-solving skills, enabling them to design systems, troubleshoot issues, and optimise processes [
15,
16]. As modern engineering increasingly leverages sophisticated technology, a deep understanding of advanced mathematical algorithms becomes essential [
17]. Fields like Artificial Intelligence (AI) and Machine Learning (ML) require extensive knowledge of linear algebra, calculus, and probability [
18]. Engineering innovation and research continually push the boundaries of mathematical knowledge, necessitating that engineers working on cutting-edge technologies, such as quantum computing or advanced materials, possess a comprehensive understanding of both applied and theoretical mathematics [
19,
20]. Ultimately, mathematics is the foundation upon which engineering principles are built, equipping students with the skills to solve complex problems, innovate, and excel in a technologically advanced and interdisciplinary world. Teaching mathematics to engineers in higher education requires a thoughtful and well-structured approach to meet the needs of the profession and prepare students for the future challenges they will face [
8,
21].
Engineering mathematics education should provide a strong foundation in core subjects, demonstrating theoretical concepts through practical examples that showcase their real-world applications in engineering problem-solving. Rogovchenko and Rogovchenko argue that mathematical modelling projects can effectively develop students’ mathematical competency, enhance their understanding of engineering concepts, and improve their communication and collaboration skills. They provide a specific project example in their work, concluding that such projects are crucial for developing the necessary skills for engineering success. Education should embrace modern software and technologies [
23], using computer simulations to reinforce theoretical knowledge and provide students with practical experience. Integrating project-based learning (PjBL) is essential, as it allows students to engage in significant projects and real-life case studies, enhancing their problem-solving and analytical skills. Interactive classrooms, where students are actively encouraged to participate in solving problems and understanding concepts [
24], foster a more dynamic and engaging learning environment. The curriculum must adapt to technological advancements, equipping students with the knowledge and skills to effectively utilize new educational technologies to maximize their learning and prepare them for continuous professional development [
25].
1.2. STEAM-Based Education and Educational Robotics
Technology and innovation play an increasingly important role in modern life, and education must evolve based on innovation and technological progress to keep pace with a changing world. Digital technologies have made a paradigm shift in the entire education system [
25]. STEAM-based education is gaining increasing prominence at universities [
26], which is particularly important for engineering higher education. Today’s university students increasingly demand educational methods that they find engaging, relevant, and interactive. STEAM education offers a dynamic and attractive learning experience [
27]. Many contemporary challenges are complex and multidisciplinary in nature. The STEAM approach allows university students to combine knowledge from various scientific and artistic fields to understand and address these challenges. The spread of problem-based learning is a consequence of the realisation that learners are left with minimal knowledge after learning through traditional, frontal teaching methods and find it difficult to apply the knowledge they acquire in other contexts. Problem-based learning provides a learning environment where learners can use and reinforce prior knowledge, learn in real-life contexts and develop their knowledge in individual or small group work [
28]. Developments over the past decade have led to the availability of a wide range of robotic learning tools, all with the common goal of innovation and motivating learners in the learning process.
Robotics and computational thinking are valuable tools for developing STEAM pedagogy and promoting the inclusion and integration of diverse groups of students. There are many robotic teaching tools at our disposal intended to encourage innovation and motivation of students during the learning process. As robots are increasingly common in our world, it is essential to integrate them into education [
29,
30]. Robots have clearly opened up new possibilities in teaching and learning. Educational robotics (ER), which involves the use of robotic techniques in education, is seen as a groundbreaking learning tool that enhances the learning environment, transforms teaching and learning methods and fosters a new educational ecosystem [
31]. Of course, most of the educational applications of ER focus on robotics-related subjects such as robot programming, robot building and artificial intelligence [
32,
33,
34].
LEGO Education focused on STEM-based learning from the beginning, even before this acronym was standard [
35,
36]. The collaboration with MIT has played a crucial role in developing LEGO’s robotics products. LOGO is a programming language developed in the 1960s at MIT, designed to make coding accessible for children. Its most famous feature is the turtle, a simple robot or on-screen graphic that can be controlled with commands, teaching basic programming concepts like sequencing and loops [
37]. In the mid-1980s, the LOGO research group began collaborating with the LEGO group because LEGO Group recognised the potential of teaching and learning with robots [
35]. The partnership between LOGO and LEGO brought programming to life, starting with LEGO/LOGO, which combined LEGO building with LOGO code. The history of LEGO robots dates back to the end of the 20th century when the LEGO Group started developing robotic kits. The first significant step was introducing the LEGO Technic series in the late 1970s, which allowed users to build more complex mechanical models. The programmable brick revolutionised the process by allowing LEGO creations to be independent and mobile, paving the way for LEGO Mindstorms [
38]. Various generations of LEGO robotics kits have been released in the last twenty years: Mindstorms NXT in 2006, NXT 2.0 in 2009, and Mindstorms EV3 in 2013. Souza et al. conducted a systematic review of the literature analysing the use of LEGO robotics technology as an instrument for teaching, considering the robotics kits and their programming environments as a combination of teaching methodologies and practices. In 2018, it was reported that the most commonly used environment and programming languages are LabVIEW and LEGO’s block-based programming language. Additionally, Souza et al. found that LEGO Robotics is utilised for teaching programming, interdisciplinary subjects, participating in tournaments, robotics, and computational thinking. Furthermore, LEGO® Robotics has been successfully used by students across various levels, including K-12, undergraduate, and graduate programs. The most recent product in the evolution of LEGO robots, SPIKE Prime, was released in 2020 and is already very popular [
39]. One reason for this is probably that the robot can be programmed in several ways, and one option is the Scratch programming language [
35]. Ersozlu et al. used a scientometrics analysis to map data from the scientific literature based on different kinds of published research and found that computational thinking (CT) in mathematics education was mostly about teaching computational skills and computer programming through practical and algorithmic thinking in engineering and STEM education, especially at the higher education level. In addition, Scratch has been the dominant tool used to teach programming skills at all levels of schooling, including higher education.
Educational robotics has been successfully used for many years as a tool to make learning more experiential and effective [
41]. Combining educational robotics with problem-based learning is not a new idea, and educational software developed for LEGO Education robot kits (WeDo 2.0, EV3, SPIKE Prime, SPIKE Essential) includes learning projects that essentially implement problem-based learning as an integral part of the design of the educational software [
35]. However, these projects focus on basic physical, biological and social science knowledge and on learning robot programming concepts [
42]. In order to target STEAM-based methodology in higher education, it is necessary to develop new robot constructs and build student projects around them.
Despite the potential of integrating robotics into teaching and learning, this integration has not yet been fully explored in university practice, especially in higher mathematics education.
1.3. Importance and Teaching of Cycloidal Curves
Roulette is a path traced by the point fixed on a curve that is rolling on another fixed curve [
43]. Cycloidal curves are a family of roulettes generated by the motion of a point attached to a circle as the circle rolls along a fixed straight line or another circle. These curves include trochoids, epitrochoids and hypotrochoids, as shown in
Table 1.
The parametric equations and graphs of the cycloidal curves are given in
Appendix 6. We note that the term central trochoid encompasses both epitrochoids and hypotrochoids [
44]. The centre of a central trochoid curve is defined as the centre of the fixed circle.
In engineering mathematics, theory and application go hand in hand. Cycloidal curves are very useful in practical life. In 1694, Philip de la Hire published a complete mathematical analysis of epicycloids and recommended an involute curve for designing gear teeth. However, in practice, it was not used for another 150 years. In 1733, Charles Camus expanded la Hire’s work and developed theories of mechanisms. Twenty years later, in 1754, Leonard Euler worked out design principles for involute gearing. Felix Wankel developed the Wankel Rotary Engine in the 1920s. Initially developed as an air compressor, the engine is now used in automobiles. The rotor is an equilateral triangle with curved sides, and the bore is an epitrochoid curve. Nowadays, epitrochoids can be found in important mechanical parts such as gears with epitrochoidal tooth profiles, cams and epitrochoidal-shaped housings for rotary internal combustion engines and rotary piston pumps. For the last case, the epitrochoid curve notes the path that the rotor tip of the eccentric shaft traces out upon revolving [
45]. Hypocycloid curves also have many important applications in engineering. One of these is the use of the astroid shape in the process of moving bus doors [
46]. In addition, central epi- and hypotrochoids can be used, for example, in surveillance or spatial coverage applications, as periodic motion primitives for human dancers or for performing complex choreographic patterns in small autonomous vehicles [
47], as well as in the context of autonomous robot navigation with collision-free and decoupled multi-robot path planning [
48]. Cycloidal curves are used in roller coaster design, architecture (Kimbell Art Museum, Hopkins Center for the Arts), and the creation of geometric patterns for stained glass windows, mosaics, and textiles [
49].
The wide range of applications above shows that cycloidal curves represent fundamental mathematical and geometric concepts indispensable in various engineering fields. In his 1913 article, Epsteen summarized the minimum content to be taught in engineering mathematics, emphasizing the importance of higher plane curves in the curriculum, including cycloids, hypocycloids and epicycloids. These curves are extremely important for mathematical foundations because the knowledge associated with them becomes relevant in the context of kinematic analysis and mechanical design. Cycloidal curves help engineering students better understand motion and force transfer principles, especially in mechanical systems [
51]. By studying such curves, students learn the precise design and efficient calculations that are essential for a variety of engineering applications. In addition, the presentation of cycloidal curves is also important in modelling the behaviour of physical motions, such as the behaviour of a pendulum [
52]. In modern computer-aided design programs, the accurate representation of cycloidal curves allows the efficient design of complex mechanical components. Cycloidal curves are not only mathematical curiosities but also fundamental tools for solving engineering problems.
In university engineering mathematics education, cycloidal curves were taught in the 18th and 19th centuries using geometric and analytical methods. Students usually learned from hand-drawn diagrams and understood mathematical equations involved in on-the-spot demonstrations and geometric proofs [
53,
54]. Kinematic models and mechanical devices were used for illustration because the derivation of the equations of cycloidal curves and the representation requires visualisation [
55]. Several of these constructions are included in Schilling’s famous collection of kinematic models [
56]. Kinematics, the study of motion, played an important role in understanding cycloidal curves, especially in analysing mechanical systems and motions. The emphasis was on geometric insights and classical physical examples. Traditional teaching methods for students at universities are outdated and not effective enough [
52]. In today’s education, modern technologies and computer simulations are now used to help understand the knowledge of cycloidal curves. Several didactical articles deal with visualising cycloidal curves using dynamic geometric software or simulation embedded in a remote experiment [
52,
57,
58]. These methods have many advantages in terms of visualisation, but they do not provide direct experimental experience. The recent research of Tessema et al. highlights the importance of a realistic, hands-on approach to learning in mathematics education, particularly in the study of geometry. Traditionally, drawing cycloidal curves is a lengthy process that requires engineering drawing knowledge. A simpler and faster way to produce curves is to have a robot draw the curve during an ER activity. By building and then testing the drawing robots, students gain first-hand experiences [
60,
61,
62,
63,
64].
1.4. 4C Learning Approach
LEGO’s philosophy is that effective learning can only be achieved through a holistic approach because learning has creative, cognitive, social and emotional aspects. The LEGO 4C principle is a pedagogical model developed by LEGO Education, focusing on four fundamental key competencies in learning [
65]. The LEGO 4C learning approach is characterised by its hands-on, inquiry-based, and collaborative nature, which aligns with constructivist and experiential learning theories. It engages students in active learning experiences where they actively construct knowledge, explore concepts, and solve problems.
By integrating the four Cs into educational activities, the LEGO 4C learning approach aims to foster creativity, critical thinking, collaboration, and communication skills in students, preparing them for success in the 21st century [
66]. These key competencies are as follows:
Connect: This first C stands for connection, meaning establishing a connection. Students should be given the opportunity to connect with the subject matter and recognize its relevant and interesting context. This allows learning to more closely align with students’ everyday lives and experiences.
Construct: The second C is construction, which means allowing students to create or build something. This could be a physical model, a project work, or a digital creation. The act of constructing enables students to deepen and apply their learning.
Contemplate: The third C is contemplate, which encourages students to reflect on the things they have created and what they have learned. This includes reflection and self-reflection, as well as critical evaluation of the application of what they have learned.
Continue: The final C is continue, which means giving students the opportunity to further develop, apply, and share what they have learned and created with others. This process can help sustain learning and apply what has been learned in practical ways.
These four phases are steps in an iterative process that should often be seen as a learning spiral (
Figure 1); the four links are not a single linear structure but a process of interlocking and dynamic circulation [
66]. The LEGO 4C principle is a framework applied to learning and teaching that helps students establish a closer connection with the subject matter and apply experiential and hands-on learning methods. This allows for a deeper understanding of learning and enriches the learning experience.
The LEGO 4C methodology has mainly gained ground in primary and secondary education [
65]. The 4C principle can also be applied in higher education because of the generational shift. We propose a methodological model based on the 4C principle to process the curriculum on cycloidal curves. Engineering students naturally show a keen interest in robotics and ICT tools, which aligns with their chosen specialisation. To help them discover the secrets of cycloidal curves, we have developed a methodology combining frontal teaching with problem-based learning, educational robotics, and dynamic geometric software in project-based learning.
1.5. The Four-Stage Methodological Model for Learning Cycloidal Curves
The first element of the four-stage model for learning cycloidal curves is frontal teaching (lecture and practice), where the theoretical material is presented, covering cycloidal curves (
Figure 2). In fact, many studies have been carried out over the last two decades on the disadvantages of frontal teaching. However, it is still the dominant teaching method in higher education [
67]. Ganyaupfu investigated that the teacher-student interactive method was the most effective teaching method over the teacher-centred approach because direct teaching is efficient in transferring knowledge but is not sufficient for deeper understanding, problem-solving and creativity. Innovative teaching incorporates technology into the teaching-learning process to create a rich and helpful learning experience for students and a rewarding teaching experience for teachers [
69,
70]. It should not necessarily be abandoned for large courses and frontal teaching, but it should be complemented by techniques where students are not passive participants. There is evidence that lectures can effectively and structurally communicate information, model reasoning, and motivate students, particularly when adequately supported by other activities [
71].
After the theoretical grounding, the topic of plane curves can be continued in specialised seminars. The second stage is to start working according to the 4C principle. The problem statement explores the possibility of producing a curve experimentally. We note that seminars are extracurricular activities. In the second phase, the focus is on attracting attention and motivation. Where possible, we choose demonstration experiments that students can carry out in small groups, documenting them and giving them the opportunity to gain direct experience. Problem-based learning (PBL) is achieved through the formulation of real-life tasks. Given that Connect aims to revive knowledge related to what has been learned previously, students are actively involved in solving the problems formulated. It is worthwhile to revive the most important theoretical knowledge; for this purpose, visualisation solutions and animations can be used in the case of cycloidal plane curves.
The third stage uses STEAM-based methods: building and programming drawing robots, and understanding how robots work. The educational robot kits give students the opportunity to explore a curve under investigation in small group activities. Working with robots requires providing building instructions for appropriate drawing robot designs and sharing conditions for working with robots. For four years, the authors have been designing drawing robots whose operating mechanisms can be mathematically deduced with precision. Using the LEGO Education SPIKE Prime robot set, educational robots have been designed to produce a wide range of representatives of the cycloidal curve family.
In spirograph-like robot models, gears are used to model the circles that generate the cycloidal curves. The aim of [
60] was to introduce the hypotrochoid family of curves and to give ideas and tools for teaching the topic. The general parametric equations of hypotrochoids were given, and several special curves that can be derived from these equations were shown. In addition, a drawing robot called Spikograph 1.0 (see
Figure 3), modelled on a Spirograph toy, was presented, which can draw different hypotrochoids, giving students a physical experience. This robot uses LEGO gears to model the slip-free rolling of the circles, and knowing the gears’ sizes, the parametric equations of the drawn curves can be easily written.
Spikograph 1.0 gave the idea to design Spikograph 2.0 (
Figure 4) for drawing epitrochoid curves; this drawing robot was presented in [
61]. The factor that most determines which epitrochoids can be drawn with the robot is the size of the suitable gears in the LEGO Education SPIKE Prime set. The diameters of the circles that define the epitrochoid correspond to the rolling diameters of the gears that model them. The rolling diameter of a gear is the diameter of an idealised disc that allows it to roll on the equivalent idealised disc of another gear that is usually meshing with it. This dimension is easy to determine since the rolling diameter of any LEGO gear, expressed in mm, is equal to the number of teeth on it.
Students can work not only with these two gearing robots in the seminars. Although Spirograph-like robots are an excellent way to illustrate the production of many notable plane curves, the principle of operation of robots in the industry follows a different path. It is important that students can work through real-life tasks on various projects; therefore, the use of a SCARA-style robot design is also possible in the seminar series (see
Figure 5). The SCARA robot is one of the common types of industrial robots [
72]. The SCARA name stands for Selective Compliance Articulated Robot Arm. The main feature of the SCARA robot is that it has a jointed 2-link arm driven by two independent motors [
73]. It is well-known that the plots generated by a Spirograph toy can also be drawn using a 2-link planar or SCARA robot after computing the inverse kinematics to get the joint angles needed to perform the correct movements. It is also a known fact that the Spirograph toy is not able to draw all types of trochoidal curves; only the curtate types can be created. However, Spirograph-like and SCARA-style robots can draw all three types of central trochoids [
63,
64].
Thanks to their construction, robots can draw an infinite number of cycloidal curves. However, the number of curves that can be drawn in the Spirograph toy is finite.
Table 2 summarises the central trochoids that can be drawn with the Spirograph, only LEGO gears and racks [
74], and the various educational LEGO drawing robots. The SCARA-style robot can be used to draw all types of central trochoids, but its principle of operation does not follow the usual definition of curve generation. A big advantage of the robot versions using gears is that the generation of curves is based on the definition. Exploring the potential of drawing robots and how to integrate them into the educational process is an ongoing process of active research.
The construction phase of the 4C principle is where the robot is built and programmed. Writing the program is also considered design because the robot can only operate with the right program. In the case of Spirograph-like robots, this refers to the operation of a single motor, whereas in the case of a SCARA-style robot, it refers to the coordinated operation of two motors.
The LEGO SPIKE Prime robot hub can be programmed in three ways, one of which includes the Scratch programming language. Developed by Mitchel Resnick at the MIT Media Lab, Scratch is an evolution of the LOGO language. This visual, block-based coding language features a drag-and-drop interface, making programming accessible and enjoyable for users [
35]. Programs for drawing robots are created in Scratch using the original software designed for the LEGO SPIKE Prime robot.
In the contemplate phase, the synthesis is given through the solution of a project task, where the task is to create an animation modelling the robot’s working principle. Students can work on the project independently or in groups, allowing for exchange and knowledge sharing. Project-based learning (PjBL) can be a very effective way to learn mathematics. PjBL involves students working on complex, real-life problems that require them to apply mathematical knowledge and skills. This approach helps students link theoretical knowledge with practical applications and develops their problem-solving and collaboration skills [
75]. In project-based learning, it is important that the projects are genuinely interesting and relevant to the students and that they solve real problems [
76]. The teacher has a key role to play in guiding and supporting students through the projects and helping them to understand the relationships and mathematical principles. Projects can also help students to see how mathematics relates to their everyday lives and to solve real-world problems. Relevant literature suggests that the link between PjBL and dynamic geometric software (DGS) is extremely useful in mathematics education [
77,
78]. DGS refers to computer software that allows the visualization and manipulation of functions, curves, and geometric shapes. These software can help students understand and visualize mathematical concepts that they can apply in PjBL projects. With DGS, students can see geometric constructions and shapes in real-time, resulting in a visual understanding that supports students in handling abstract mathematical concepts better. The DGS provides an interactive platform through which students can experiment and modify geometric constructions on their own, significantly contributing to the development of active learning and an experimental approach. The link between theoretical and practical aspects is greatly facilitated by using DGS, as students can immediately see how functions, geometric shapes and relationships change when they change parameters or manipulate constructs. Experiences have shown that the combined use of PjBL and DGS helps make mathematics teaching more interactive and understandable [
78,
79,
80]. Students will be able to apply the mathematical knowledge they have acquired through DGS in real projects and will be able to combine theoretical and practical aspects more easily.
In the fourth stage of 4C, additional project tasks are connected to the studied curve. It is recommended that homework be solved using DGS. There are different types and versions of DGS. One of the most commonly used DGS is GeoGebra [
79]. The application can be used for geometric and algebraic analysis. It offers several tools for visualising functions, drawing and manipulating geometric shapes and understanding mathematical concepts [
80]. Desmos was originally a graphing calculator application but has since been extended to include DGS functionality. Desmos is a compelling application for visualising functions and curves and helping to understand mathematical expressions [
81], so it is worth using this DGS for engineering mathematics courses. Another advantage is that Desmos is also an excellent tool for project-based learning. Real-time graphs, data visualisation, and interactive shape generation help students present their projects clearly and interestingly and provide opportunities for collaboration and interaction between students. For example, several students can collaborate on a project and see each other’s work in real time. In Desmos, students are able to animate graphs, which can help them better understand mathematical relationships and changes [
82].
A well-designed methodology helps to structure and manage the learning process. It sets out the expected goals and outcomes for learners and the steps to be followed to achieve them. Based on the 4C principle, the four-stage methodological model for learning cycloidal curves considers learners’ individual needs, interests and abilities. It provides a flexible structure for differentiated learning experiences to ensure all students succeed. This method creates a motivating and engaging learning environment. Students enjoy learning through exciting and challenging tasks, contributing to long-term engagement and success.
Using the four-stage model for learning cycloidal curves, ellipses, cycloids, cardioids, astroids, and roses were discussed. The application of the four-stage model for learning cycloidal curves is illustrated in
Appendix 7 with the example of teaching cardioid.