The shipbuilding industry demanded a new principle for the uphill welding of sections with hollow and full welded seams. The welded parts are made by ferritic steel, so a basic principle based on permanent magnets was preferred and guided to a linkage based walking mechanism.

Analysis of linkages, cam mechanisms, gear mechanisms and geared linkages with Mechanism Developer (MechDev) Due to the development of servo motors, complex motion tasks are less and less often solved with the help of unevenly translating mechanisms from classic mechanism theory. Nevertheless, there are some reasons for using unevenly translating mechanisms, but there are fewer and fewer engineers with the necessary expertise to design them. At the Institute of Mechanism Theory, Machine Dynamics and Robotics (IGMR) of RWTH Aachen University, the software Mechanism Developer (MechDev) is developed, which allows the design engineer to intuitively design a mechanism without specialized knowledge. This article shows the functional range of the software by means of a practical application example.

Design and manufacture of four-bar linkages by means of design libraries and additive manufacturing The following article presents a development and manufacturing process in which a mechanism is designed, constructed and manufactured by means of additive manufacturing based on a motion task under geometric and functional boundary conditions. The Matlab library SG-Lib (Solid Geometry) is used, which is developed at the chair MiMed and is available for download at GitHub for all those who want to design and build mechanisms.

The article deals with a spherical handling system and goes into detail about the belt drive used on the curve. With the aim of improving performance, the existing sliding friction was transferred to a roller bearing and comparatively examined with regard to the drive performance. With the help of a simulation model of the curve guide in SimulationX it is checked whether the drive design of the belt is also possible without a real model. A further investigation compares the theoretical or simulated positioning accuracy with the real accuracy of the system at the TCP.

Analytical calculation of C2-continuous rise-to-dwell motions with specified dwell tolerance In this paper, an analytically computable approach for the synthesis of C2-continuous rise-to-dwell motions with a given dwell tolerance is presented. Motion tasks of this type frequently arise in the development of processing machines. The presented approach not only enables the efficient online computation in flexible mechatronic applications, but also shows favorable properties for the application in electromechanical drive systems.

On Visualizing Motion Functions in the Velocity-Acceleration Plane / Abstract In this contribution we discuss the advantages and disadvantages of visualizing motion functions in the velocity-acceleration-plane which was introduced by Broquère for depicting time-optimal seven-segment profiles with restricted jerk. His representation will be used in this contribution and it will be extended for jerk-continuous functions.

Cycle time-optimal motion design using normalized motion functions of VDI 2143 for rest-in-rest motion tasks / Abstract This article summarizes the most important extensions of the second edition of the VDI 2143 guideline, whose first edition has been tried and tested for over 40 years and is due to be republished soon. The guideline committee made a conscious decision to expand the complex of motion design of cam gears to include motion control systems in the second edition, in order to compile a set of rules that corresponds to the state of the art. Further design methods of electromotive drives are also presented to demonstrate possible tool applications utilized within the new guideline.

Reducing of tracking-deviation on controlled drives. The subject of this paper is an experimental method to determine an optimal torque feedforward-signal to get minimal tracking-deviation. The method is limited for periodic working mechanism with one degree-offreedom.

Synthesis of deformation behavior of compliant elements by phase portrait method Mechanisms with compliant elements have a high lightweight potential due to their reduced diversity and weight of components. For their targeted synthesis, a so-called phase portrait method has been presented in this article [1], which allows the prediction of large deformations with sufficient accuracy. However, the mathematical treatment of the inherent differential equations and derivation of a phase portrait or the concrete deformation pattern are complex and time-consuming. To solve this problem and to achieve a fast and clear representation, this article also includes the development of a graphical user interface (GUI) for the synthesis of the deformation behavior of compliant elements using the phase portrait method.

Controlling of compliant-mechanisms with reinforcement learning Driving compliant-mechanisms to target positions is particularly challenging since it is not or hardly possible to set up the inverse kinematics with analytical models. On the basis of an exemplary compliant-mechanism, this work shows how machine learning methods can be applied to successfully learn the corresponding kinematics. This allows statements on how the actuators have to be controlled in order to reach arbitrary points with the mechanism.

A method for optimising compliant mechanisms In this paper, a method is presented which can be used to optimize the deformation behavior of compliant mechanisms. The method is based on the theory of large deformations of rod-like structures. The calculation is carried out with numerical solution methods in Python. For the optimisation, flexure hinges are displaced along a given beam axis. Through parameter studies of three mechanisms, the effect of the hinge position on the deformation behaviour is first highlighted. Finally, the calculation method is successfully verified using the results obtained from the parameter studies.

The possibilities for simulating and analyzing planar mechanisms with web applications are currently very limited. Therefore, an impulse-based approach for modeling and simulating planar mechanisms using Nodes and Constraints is presented, which completely ignores kinematic quantities. The developed Javascript simulation libraries and their usage is described by many examples. Finally, some complex examples show the power of the new approach.

Load-free tooth contact analysis with the toolbox next|Gear for optimization of micro and macro geometry of special gearboxes This article shows the calculation and optimization of the micro geometry of the HypoGear gearbox. For this purpose, the matlab toolbox next|Gear was used, which is based on the conjugation of tooth flanks according to the general law of gearing. A modular structure with numerous function blocks for basic geometry calculation, tooth profile design, conjugation workflows, flank modification and also evaluation algorithms, such as load-free tooth contact analysis, enables the conceptual design and optimisation of special gears.

Non-coaxially coupled planetary gearboxes for introducing additional movements into the main spindle of a machine tool. Resource and cost efficiency for machine tool drive systems means, among others, operation at optimum working points. The article shows an example of a drive concept combined of direct drive and planetary gears, in which an additional drive supports a main spindle as required. The basis is the non-coaxial coupling of e. g. open planetary gears, used in three-shaft operation. First, methods of calculation and conception of non-coaxially coupled, especially open planetary gears are presented. Two drive concepts (orbital machine tool; demand-oriented main spindle support) exemplarily show the possibilities of this gear coupling. A selection algorithm incl. reduction of possible coupling variants by minimum requirements is referred to.

Investigation of passive steering concepts using MATLAB SIMULINK for their application in a modified Tram 2000 The rail vehicle industry is one of the most traditional and thus also rather conservative industries in mechanical engineering. Nevertheless, alongside innovative topics such as the advancing autonomisation or the establishment of hydrogen fuel cell technologies, there are also concepts for the active guidance of rail vehicles. As a young, up-and-coming startup, we at Traila are developing just such an active steering concept (Traila Active Steering), which, in addition to noise emissions, above all reduces wear in the rail-wheel contact. In our current project phase, we have taken over a tram type T2000 in cooperation with the Zurich Transport Authority (VBZ), with which we can now provide prototypical functional proof of our technology. Within the framework of safety-relevant investigations, passive control concepts as well as active control concepts were examined for the selfdeveloped, actively controlled bogie. In this presentation, different kinematics for passive control are investigated with regard to their adaptation for the Tram 2000, using a specially developed rail-wheel library in MATLAB SIMULINK. In addition to the dynamic investigations on the model, the presentation focuses in particular on an assessment of passive safety with the help of the tools available in MATLAB SIMULINK. It is shown how, based on hydraulic, mechanical, control and external libraries, a domain-spanning multi-physical model is built up as a virtual twin of the T2000, in particular of our modifications, and processed for use in a HIL test bench.

The multi mover planar motor system Xplanar combines the attributes of traditional transport and handling systems such as six axis robots, linear motors, or automated guided vehicle (AGVs). XPlanar offers a dynamic and precise positioning of products on movers in up to 6 axis and an individual transport of products through the entire manufacturing process. The unique magnetic levitation effect of the movers minimizes wear and tear, noise emissions, and maintenance time. In combination with central control and programming the XPlanar system enables new approaches to design modern and highly flexible production machines.

Comparison of different types of joints for origami based engineering The following article is intended to provide guidance as to which foldable joints are advantageous for the use in robotics. For this purpose, three joint types are tested. The joint types considered are chosen to cover the most widely used 3D printing technologies.

During design process of a robot a lot of challenges have to be meet. Increased operating speed should maintain required positioning accuracy. Adams as well-known software for multi body dynamics simulation could help to reduce time of development process significantly. Not only kinematic model should be considered but the control system as well, to be able to provide correct positioning in case of different scenarios as higher payload value, higher speed or backlash of the gearbox. Nowadays, the best approach seems to be to use a tool that will use the same simulation model, but which will also be able to provide multi-physics results.

Development of a haptic glove system for use in virtual reality Force feedback systems improve the quality of virtual reality (VR) and are suitable for application in Human-Machine Interface. The following article presents the development of a freely available haptic feedback glove that can be manufactured with ease. The developed glove consists of a novel force transmission system that is optimised for additive manufacturing. The proposed system includes several potentiometers and an IMU-Sensor for calculating the position and orientation of the hand. Furthermore, the VR-scene developed for testing the gloves and the corresponding interface are presented.