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authorContributionM. Berger
Chemnitz teaching and research focus in the field of transmission technology

The current Chemnitz teaching and research focus in the transmission technology environment is influenced on the one hand by the historical subject areas, on the other hand determined by the new requirements in the mechanical engineering environment. In contrast to the historical education of the students in the mechanical engineering course, the course content for the development and calculation of unevenly translating gears can now only be offered as electives in the master's course after the reorganization of the course content as a result of the changeover to the two-part bachelor's and master's degree. Due to the expected future knowledge gaps of young engineers, especially with regard to the theoretical basics and tools for the subject of transmission synthesis, it appears necessary to make the processes and methods of transmission synthesis available as additional features in common software and CAD applications. Possible solutions for this include: to develop additional functionalities for CAD programs or simulation environments or to develop algorithms externally, e.g. B. to be implemented using MATHCAD synthesis worksheets with modularly structured function blocks.
Drive technology research focuses today are characterized by the fact that optimal solutions i. A. cannot be achieved solely through optimal mechanical assemblies Rather, the focus is on the best possible combination and symbiosis of assemblies for developing efficient overall mechatronic concepts. In addition to electronic and software-related issues, material and energy-efficient aspects are also increasingly the focus. In contrast to the working method that used to be heavily influenced by the experimental field, detailed virtual prototypes now play a decisive role.

A. FrickeT. Brix
thinkMOTION - Europe's gateway to the world of gearboxes

At the end of 2010, the EU project thinkMOTION started, the main objective of which is the internet-based provision of information from the field of motion technology for a wide range of users. The material to be collected throughout Europe as part of the project ranges from forgotten, historically significant treasures to the latest research results. A wide variety of information sources, such as books, patent specifications, articles, drawings, representational models, etc., are digitized, supplemented with metadata and made available on the Internet in the form of text documents, photos, videos, interactive animations or formalized descriptions of transmission technology solutions. From a technical point of view, the work in the thinkMOTION project is based on the results of the Digital Mechanisms and Gear Library (DMG-Lib.org), which has now been established as an online library and which was set up with financial support from the German Research Foundation. The DMG-Lib workflow and the DMG-Lib tools have been adapted to the requirements of distributed work on a European level. The content created by thinkMOTION is collected on the DMG-Lib platform and presented in different ways. It is important that the DMG-Lib content is also accessible via the Europeana online library, which as the central European metaportal already includes millions of digitized objects. In addition to a brief presentation of the thinkMOTION project, the following statements focus on essential aspects of the workflow used, the clarification of rights and the problem of multilingualism.

E.C. LovaszJ. Müglitz
Mechatronics and welding technology

In the globalized world, creativity and new ideas are among the few opportunities to gain a competitive advantage.
In a subject area - as in the present case of mechanical engineering - which is at least partially considered to be no longer up-to-date and whose specific knowledge runs the risk of being forgotten, those who still have this knowledge have a wide range of fields of activity. If it is possible to combine old, non-uniform transmission gears with new ones, computer technology and the possibilities of modern production technology, a unique position can emerge.
For small companies with little market and sales power in particular, niches are opening up in which technical solutions can be developed and marketed relatively undisturbed by the major players in the industry.

U. Hanke
Pros and cons of new synthetic approaches

In the globalized world, creativity and new ideas are among the few opportunities to gain a competitive advantage.
In a subject area - as in the present case of mechanical engineering - which is at least partially considered to be no longer up-to-date and whose specific knowledge runs the risk of being forgotten, those who still have this knowledge have a rich field of activity. If it is possible to combine old, non-uniform transmission gears with new ones, computer technology and the possibilities of modern production technology, a unique position can emerge.
For small companies with little market and sales power in particular, niches are opening up in which technical solutions can be developed and marketed relatively undisturbed by the major players in the industry.

R. Brown
Made-to-measure synthesis of linkage gears - a critical examination of a new synthesis approach using so-called "standardized gears"

In the globalized world, creativity and new ideas are among the few opportunities to gain a competitive advantage.
In a subject area - as in the present case of mechanical engineering - which is at least partially considered to be no longer up-to-date and whose specific knowledge runs the risk of being forgotten, those who still have this knowledge have a wide range of fields of activity. If it is possible to combine old, non-uniform transmission gears with new ones, computer technology and the possibilities of modern production technology, a unique position can emerge.
Particularly for small companies with little market and sales power, niches are opening up in which technical solutions can be developed and marketed relatively unaffected by the big players in the industry.

H. Niggemann
Optimization of cam gears with the help of parameterized laws of motion in multi-body simulation

The movement design for cam gears or mechanisms with controlled drives determines the achievable working speed and movement accuracy. Depending on the application, movements are designed using different mathematical approaches.
Established methods are the section-by-section definition of transfer functions on the basis of polynomial motion laws, the description of motions using splines or harmonic synthesis.
In the gear technology / simulation division of Heidelberger Druckmaschinen AG, a program system was developed for the design of polynomial motion functions by coupling motion design and multi-body simulation. The system enables the parameterization of motion laws in the simulation model of a transmission, the efficient, automatic simulation of motion design variants and the motion optimization according to any mechanical measured variables of the multi-body simulation.
The corresponding design process is presented using the example of the front lay transmission of a sheet-fed offset printing machine. In particular, it is shown that the method can lead to extremely cheap solutions that are difficult to find with traditional approaches to motion design.

B. Corves
Coupling cam stepping mechanism based on a five-link crank mechanism

On the basis of a five-link crank mechanism, under certain boundary conditions with regard to the kinematic dimensions and the transmission ratio between the two drive cranks, radially symmetrical coupling curves can be generated, which can be used to generate a step gear through an appropriately dimensioned and articulated additional double stroke.
In the following article, after a brief abstract of the literature on five-link gears in general and their use as ratchet or indexing gears in particular, the determination of the curvature properties of the coupling curves of five-link gears is discussed, with the help of an interactive geometry program also showing the extent to which the geometric determination of the curvature properties can be used to generate the best possible indexing gear.

K. H. Modler
Straight guides with the lemniscate handlebar type II

In this article, the calculation bases for straight lines with the asymmetrical Watt’s handlebar (lemniscate handlebar type II) are presented. It is described how gearboxes of this type can be calculated with point-wise optimal or area-wise fully balanced straight line guidance. The approximate straight line of the centric slider crank is the starting point for the development of straight lines with the lemniscate handlebar type II.

W. Lohr
Possible uses of the 3D CAD systems Catia V5 and Pro / ENGINEER in gear technology

CAD systems are the most common tools used by a designer. Using the example of some classic methods of transmission synthesis, it is examined whether and how these methods can be adopted into the CAD work environment with or without modifications. Possibilities are shown how the 3D CAD systems Catia V5 and Pro / Engineer Wildfire can be used to solve movement tasks. Compared to manual drawing, there are expanded options for gear synthesis without the CAD operator needing knowledge of programming routines in the CAD system.

A. Kecskemethy
Rigid subchain identification of multi loop kinematic chains with the method of kinematical transformers

Structural design of mechanisms in a human-machine interaction manner is becoming an important new trend in the conceptual design of mechanism-based products or systems. Rigid subchains, which have zero or negative degrees of freedom, usually exist in closed kinematic chains, especially in those with multiple loops. This paper proposes an efficient solution for the problem of rigid subchain identification of multi-loop kinematic chains. First, the array representation of the loops of kinematic chains is introduced and the operations of loops are presented. Then, the concept of the basis loops and their selection rules are proposed. Base on the base loops, the graph of kinematical network of kinematic chains is established. A new method grounded on the kinematical network is proposed for rigid subchain identification in multi-loop kinematic chains in the end. Some identification examples are given to show the effectiveness of the method.

T. Thümmel
Use of proper motion to identify kinetic parameters of mechanisms

The article deals with dynamic models for drive systems with mechanisms that are particularly used in high-speed processing machines. An overview of model levels, parameters and methods of parameter identification is given. The model comparison between experiment and simulation plays an essential role. The advantageous use of self-movement or quasi-self-movement as an indicator function for the step-by-step determination of parameter values ​​is worked out and demonstrated on the basis of the inertia parameters of the individual bodies. In addition to the conventional procedure, numerical optimization is also used with selected parameters. The crank arm of a mechanism test bench serves as an example for the model comparison.

L. hundredweight
Mathematical formalism for the formation of rigid body models for compliant mechanisms

Microtechnology is inconceivable without compliant mechanisms. The monolithic structure in particular makes them attractive for applications in the micro range. It is precisely the properties that bring advantages to the technology that make it difficult to investigate theoretically. In this contribution, a formalism for setting up rigid body system models is demonstrated and substantiated with examples.

G. Lonij
e-Kinematix: Virtual research environment to support transmission development

In the e-Kinematix project, a virtual research environment is to be set up to support the development of movement devices. For this purpose, technologies for project organization, implementation and documentation are to be provided. Tools for administration, research, synthesis and analysis are created in individual modules. Documenting the results of the work steps and linking the collected data is particularly important during development. The e-Kinematix project is based on the e-research environment eSciDoc, the digital mechanism and gear library (DMG-Lib) and the Gecko application. The combination creates a comprehensive tool to support the development process.

F. Allmendinger
Analysis of bone movements in the human wrist and synthesis of replacement gears to solve the inverse dynamic problem

The wrist or wrist connects the forearm with the metacarpal and gives it two degrees of rotational freedom. The movements in these degrees of freedom are called flexion / extension and radial / ulnar abduction. In contrast to other joints in the human musculoskeletal system, the structure of the wrist does not resemble a technical ball joint, as is approximately the case for the hip or shoulder, for example. Rather, the carpal consists of eight individually shaped bones, which are embedded in a complex soft tissue system and whose individual twisting and displacement ensure the mobility of the metacarpal and a large amount of power transmission.
The movement paths of the bones are determined from CT images of the carpal bones of living test persons in various static positions of the metacarpal. Building on this, it is shown by way of example how these movements are analyzed in order to make a synthesis of replacement transmissions possible.

F. Irlinger
Kinematics of an endoscope manipulator

This article presents the development of the kinematics of an endoscope manipulator system (EMS). It is used in the surgical therapy of diseases in the paranasal sinuses, for example in FESS (Functional Endoscopic Sinus Surgery). The system enables two-handed operation. The article summarizes the work according to [Krinninger 2011].

S. Linß
Design of flexure joints for targeted use in flat, flexible mechanisms

Cohesive flexural joints with concentrated resilience enable the deformation behavior of monolithic resilient mechanisms to be influenced in a targeted manner through geometric design. In this article, the potential of prismatic solid-state joints with different polynomial-shaped as well as simplified recess contours for reducing the stress-deflection ratio is shown as an example. Since these joints are used particularly in the field of precision engineering, the shifting of the rotational axis is considered as an additional criterion as an influencing factor on the positioning deviation of a monolithic steering wheel guide.

H. guys
About three transmissions from Karl Hoecken from Berlin - viewed and recalculated afterwards

CAD systems are the most common tools used by a designer. Using the example of some classic methods of transmission synthesis, it is examined whether and how these methods can be adopted into the CAD work environment with or without modifications. Possibilities are shown how the 3D CAD systems Catia V5 and Pro / Engineer Wildfire can be used to solve movement tasks. Compared to manual drawing, there are expanded options for gear synthesis without the CAD operator needing knowledge of programming routines in the CAD system.

M. Beitelschmidt
The introductory internship for mechatronics students at the TU Dresden

In 2010, a robot competition for freshmen students of mechatronics took place for the first time as part of a project week at the Technical University. The aim of this was to give the students increased motivation for their studies and to give them an overview of the most important elements of mechatronics based on the topic of robotics. Four different tasks were developed that were part of a relay competition. Lego Mindstorms NXT 2.0 formed the basis of the robots, programming with National Instruments LabVIEW. This article describes the organization and implementation of the project as well as the experience gained.

S. Gössner
A physics engine for web-based mechanism simulation - results of a study

The article presents the results of a study that investigates the suitability of the characteristic concepts of a physics engine for use in simulation and analysis software for plane mechanisms as part of an internal university research project. An additional special feature is the requirement to design this software as a pure web application. The relevant mechanical fundamentals and the numerical methods used are also dealt with in a brief manner, as are the architecture and properties of the web application that has been created. A number of examples illustrate their possible uses.

C. Woernle
Mechanisms for the kinematically non-uniform guidance of centrifugal masses

Modern, highly charged internal combustion engines generate highly irregular torques on the crankshaft. In order not to transfer the resulting vibrations to the gearbox and the drive train, flywheels are used to increase inertia and mass-spring-damper systems for isolation or absorption. The vibration-reducing effect of a flywheel can be expanded by connecting the flywheel to the crankshaft with a non-uniform transmission, rather than rigidly. For this purpose, various transmission variants are described and the design of a gear coupling is presented with the help of a multi-body model.

F. Ebert
Holistic system simulation of complex drive systems with non-linear characteristics

When designing modern, energy-efficient drive systems, it is necessary to take a holistic view of the dynamic interaction of all components involved. For a drive system, holistic means that the project engineer can model and calculate it in a working environment, from the mechanical drive train to the drive motors to the components of the control and regulation technology. Structural and parameter optimization are often in the foreground here.
The article shows the development of new 2D library elements for the simulation of level coupling and belt transmission structures, which were developed for an existing simulation environment. By defining exact interfaces, these new 2D library elements can be combined with any existing 1D library elements, such as B. drive and control components can be linked. On the basis of selected examples, not only the connection options for drive and control technology are shown, but the scope of the new coupling and belt transmission elements is also demonstrated.