*Editorial* **Multibody Systems with Flexible Elements**

**Marin Marin 1,\* , Dumitru Băleanu 2,3,4,\* and Sorin Vlase 5,6,\***

	- Transilvania University of Bras,ov, 500036 Bras,ov, Romania

### **1. Introduction**

The formalism of multibody systems offers a means of computer-assisted algorithmic analysis and a means of simulating and optimizing an arbitrary movement of a possible high number of elastic bodies in the connection. The domains where researchers apply these methods are robotics, simulation of the dynamics of vehicles, biomechanics, aerospace engineering (helicopters, the behavior of cars in the gravitational field), internal combustion engines, gearboxes, transmissions, mechanisms, the cellulose industry, simulation of particle behavior (granulated particles and molecules), dynamic simulation, military applications, computer games, medicine, and rehabilitation. As a result, multibody systems have become widely used in all industries, such as in automotive engineering, airspace engineering, construction, and manufacturing [1–8]. It is for these reasons that there is continuous research into the development of the field. Some of this research is presented in this volume, in which a large group of researchers will present their latest findings. We hope that researchers will find an interesting and useful volume of information for their future work, but that the results will also be used by engineers for practical applications.

#### **2. Statistics of the Special Issue**

The statistics of papers called for this Special Issue, related to published or rejected items, are as follows [9–23]: 26 total submissions, of which 15 were published (57.6%) and 11 rejected (42.3%). The authors0 geographical distribution is shown in Table 1, and it can be seen that the 38 authors are from 9 different countries. Note that it is usual for a paper to be written by more than one author, and for authors to collaborate with authors with different affiliations or multiple affiliations.

**Table 1.** Geographic distribution of authors by country.


**Citation:** Marin, M.; B˘aleanu, D.; Vlase, S. Multibody Systems with Flexible Elements. *Symmetry* **2021**, *13*, 1359. https://doi.org/10.3390/ sym13081359

Received: 5 July 2021 Accepted: 6 July 2021 Published: 27 July 2021

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**Copyright:** © 2021 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 (https:// creativecommons.org/licenses/by/ 4.0/).

#### **3. Authors of the Special Issue**

The authors of this Special Issue and their main affiliations are summarized in Table 2, and it can be seen that there are three authors on average per manuscript.




**Table 2.** *Cont.*

#### **4. Brief Overview of the Contributions to the Special Issue**

The analysis of the topics identifies or summarizes the research undertaken. This section classifies the manuscripts according to the topics proposed in the Special Issue. There are three topics that are dominant, namely: modeling of the multibody system with symmetries, symmetry in applied mathematics and analytical methods in the symmetric multibody systems.

**Author Contributions:** Conceptualization, M.M., D.B. and S.V.; methodology, M.M., D.B. and S.V.; software, M.M., D.B. and S.V.; validation, M.M., D.B. and S.V.; formal analysis, M.M., D.B. and S.V.; investigation, M.M., D.B. and S.V.; resources, M.M., D.B. and S.V.; data curation, M.M., D.B. and S.V.; writing—original draft preparation, S.V.; writing—review and editing, M.M., D.B. and S.V.; visualization, M.M., D.B. and S.V.; supervision, M.M., D.B. and S.V.; project administration, M.M., D.B. and S.V. All authors have read and agreed to the published version of the manuscript."

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

