# Additive Manufacturing as an Essential Element in the Teaching of Robotics

^{1}

^{2}

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. AM Changes a Course Syllabus

- Planar robots: forward and inverse kinematics. The next topic is represented by velocity and kineto–static analyses, the Jacobian matrix is introduced as well as the concepts of velocity and manipulability ellipsoids. During this first stage, great attention is set on the identification of the workspace of the machine. Once presented the notions of kinematics, dynamic models of the example robot are introduced. Even if the course is mainly focused on serial kinematic robots, some examples of parallel kinematic architectures are presented highlighting the pros and cons of the two families of robots.
- Coordinate transform and 3D kinematics: the concept of coordinate transformation is introduced adopting the pose matrix approach. Equipped with these notions the kinematic analysis is extended to three-dimensional robots. DH parameters are presented and differential kinematics is introduced. At this point, student are advised of the difficulty of solving the inverse kinematic problem for a generic serial manipulator.
- Dynamics: as for the kinematic analysis, dynamics is extended to three dimensional systems. Action, inertial and momentum matrices are introduced, and equations of motion for a generic serial manipulator are presented both using Newton equations and Lagrange formulation.
- Trajectory planning: various kinds of motion laws are presented analyzing in which conditions is more convenient to use a specific one with respect to another. Among the algorithms presented it is worth to mention: point to point motion laws (e.g., TVP, cycloidal), splines, linear polynomial interpolation with parabolic blends.
- Control algorithms: different control algorithms and architectures are presented, centralized and decentralized ones, in joint space and workspace. Examples of force control architectures are also provided.
- Mechanical components: dedicated mechanical components for robotics are presented, such as harmonic and cycloidal reducers, rotary ball spline, roller pinion systems, grippers and the like.

## 3. Rapid Prototyping in Electronics

#### Programming and Control:

## 4. Project Description and Assessment

- Study of the kinematic configuration assigned;
- Numerical analysis to determine working space and motor torque required;
- Manual control (joystick);
- Mandatory mission to be assessed for the challenge at the end of the course;
- Task of choice.

## 5. Course Development and Outcomes

#### 5.1. Mechanical Design

- Task constraints;
- Dependency on the kinematic parameters;
- Servo minimum displacements and range;
- Power requirements.

#### 5.2. 3D-Printing

#### 5.3. Multibody Simulation:

#### 5.4. Trajectory Planning:

#### 5.5. Competition and Project Evaluation:

## 6. Can AM Enhance Didactics?

#### 6.1. First Section

#### 6.2. Second Section

#### 6.3. Third Section

## 7. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## Abbreviations

AM | Additive manufacturing |

FDM | Fused deposition modeling |

SCARA | Selective compliance assembly robot arm |

DH | Denavit–Hartenberg |

TCP | Tool center point |

## References

- Giberti, H.; Cinquemani, S. Motor-reducer sizing through a MATLAB-based graphical technique. IEEE Trans. Educ.
**2012**, 55, 552–558. [Google Scholar] [CrossRef] - Giberti, H.; Cinquemani, S.; Ambrosetti, S. 5R 2dof parallel kinematic manipulator—A multidisciplinary test case in mechatronics. Mechatronics
**2013**, 23, 949–959. [Google Scholar] [CrossRef] - Go, J.; Hart, A.J. A framework for teaching the fundamentals of additive manufacturing and enabling rapid innovation. Addit. Manuf.
**2016**, 10, 76–87. [Google Scholar] [CrossRef] - Ford, S.; Minshall, T. Invited review article: Where and how 3D printing is used in teaching and education. Addit. Manuf.
**2019**, 25, 131–150. [Google Scholar] [CrossRef] - Giberti, H.; Fiore, E. The “robot mechanics” course experience at Politecnico di Milano. Mech. Mach. Sci.
**2018**, 49, 583–590. [Google Scholar] [CrossRef] - Piepmeier, J.A.; Bishop, B.E.; Knowles, K.A. Modern robotics engineering instruction. IEEE Robot. Autom. Mag.
**2003**, 10, 33–37. [Google Scholar] [CrossRef] - Nagai, K. Learning while doing: Practical robotics education. IEEE Robot. Autom. Mag.
**2001**, 8, 39–43. [Google Scholar] [CrossRef] - Krotkov, E. Robotics laboratory exercises. IEEE Trans. Educ.
**1996**, 39, 94–97. [Google Scholar] [CrossRef] - Robinette, M.F.; Manseur, R. ROBOT-DRAW, an internet-based visualization tool for robotics education. IEEE Trans. Educ.
**2001**, 44, 29–34. [Google Scholar] [CrossRef] - Vandevelde, C.; Wyffels, F.; Ciocci, M.C.; Vanderborght, B.; Saldien, J. Design and evaluation of a DIY construction system for educational robot kits. Int. J. Technol. Des. Educ.
**2016**, 26, 521–540. [Google Scholar] [CrossRef] - Wong, N.; Cheng, H.H. CPSBot: A Low-Cost Reconfigurable and 3D-Printable Robotics Kit for Education and Research on Cyber-Physical Systems. In Proceedings of the 12th IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications (MESA), Auckland, New Zealand, 29–31 August 2016; pp. 1–6. [Google Scholar]
- Ceccarelli, M. Robotic teachers’ assistants. IEEE Robot. Autom. Mag.
**2003**, 10, 37–45. [Google Scholar] [CrossRef] - Armesto, L.; Fuentes-Durá, P.; Perry, D. Low-cost Printable Robots in Education. J. Intell. Robot. Syst.
**2016**, 81, 1. [Google Scholar] [CrossRef] - Murphy, R.R. ‘Competing’ for a robotics education. IEEE Robot. Autom. Mag.
**2001**, 8, 44–55. [Google Scholar] [CrossRef] - Jung, S. Experiences in Developing an Experimental Robotics Course Program for Undergraduate Education. IEEE Trans. Educ.
**2013**, 56, 129–136. [Google Scholar] [CrossRef] - Castelli, K.; Giberti, H. A preliminary 6 Dofs robot based setup for fused deposition modeling. Mech. Mach. Sci.
**2019**, 68, 249–257. [Google Scholar] [CrossRef] - Legnani, G.; Fassi, I. Robotica Industriale; EAN: Città Studi, Torino, Italy, 2019. [Google Scholar]
- Khoo, Z.X.; Teoh, J.E.M.; Liu, Y.; Chua, C.K.; Yang, S.; An, J.; Leong, K.F.; Yeong, W.Y. 3D printing of smart materials: A review on recent progresses in 4D printing. Virtual Phys. Prototyp.
**2015**, 10, 103–122. [Google Scholar] [CrossRef]

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Castelli, K.; Giberti, H. Additive Manufacturing as an Essential Element in the Teaching of Robotics. *Robotics* **2019**, *8*, 73.
https://doi.org/10.3390/robotics8030073

**AMA Style**

Castelli K, Giberti H. Additive Manufacturing as an Essential Element in the Teaching of Robotics. *Robotics*. 2019; 8(3):73.
https://doi.org/10.3390/robotics8030073

**Chicago/Turabian Style**

Castelli, Kevin, and Hermes Giberti. 2019. "Additive Manufacturing as an Essential Element in the Teaching of Robotics" *Robotics* 8, no. 3: 73.
https://doi.org/10.3390/robotics8030073