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Within the further development of a special mechanical representation of the human circulatory system the CVELoop at the Department of Cardiovascular Engineering at RWTH Aachen University, a contractive MockHeart was developed. This MockHeart simulates a healthy heart in the CVELoop. In opposition to all previous cardiovascular system simulators, the left ventricle is externally driven by several cam mechanisms. These cam mechanisms provide the necessary power to create the pressure-volume-work for the fluid circulation but also the important time dependent radial contraction, which is the most influential degree of Freedom in the human heart. The aim is to produce a MockHeart providing valid boundary conditions for the connected VAD (Ventricular Assist Device). The systematic approach of the development of the mechanism is performed based on an accurate measurement of the kinematic properties of a healthy human heart at RWTH Aachen University with the speckle tracking echocardiography-procedure.

A Non Uniform Rational B-Spline (NURBS) is used for synthesizing the motion curve of cam mechanisms because it is flexible and satisfies arbitrary boundary conditions from the working requirement of machinery systems. For using NURBS curve as motion curves of cam mechanisms, selecting the knot vector is very important. This work presents the effect of the knot vector on the displacement, velocity, acceleration, and jerk curves. The linear system of equations for solving the cam motion is also presented. A general computation of the knot vector of NURBS for synthesizing the motion curve is presented. Several examples illustrate this research.

In cam design process, synthesizing the motion curves is very important because of the effect of motion curves to cam size, force, and vibration. Thus, improving the kinematics of cam curves is significant. This paper presents a general synthesis of motion curves of cam mechanisms. A Non Uniform Rational B-Spline (NURBS) is used to improve the kinematics. The linear system of equations is established to determine motion curves for arbitrary boundary conditions of displacement, velocity, acceleration, and jerk. By controlling the weight parameters of NURBS, the peak values of acceleration and jerk can decrease. Several examples are presented to demonstrate this research. The results are also compared with traditional motion curves.

Due to shorter product lifecycles and a rising demand for customization, flexibility and adaptability of assembly processes will become key elements in achieving sustainable success of industrial production in high-wage countries. Cognition-enhanced self-optimization as presented in this chapter has been identified as one major contributor to the enhancement of this flexibility and adaptability. The proposed approach to realize cognition-enhanced self-optimization for assembly systems in a broad range of application domains is to integrate dynamic behavior allowing reactions on disturbances and unforeseen events by dynamically adapting the target objectives of internal control loops. Unlike the approach of traditional closed control loops in which target objectives of an optimization process are determined in advance, this approach defines goal functions as dynamically adaptable throughout the process. The chapter concludes with two application examples—one dealing with the assembly of large-scale components (airplane structures) and the other with small component assembly (micro-optical elements)—presented to illustrate the industrial deployment of self-optimization for assembly tasks.

This paper addresses the dynamic control of a 2PRP-2PPR vertical planar parallel manipulator. This proposed manipulator can be used for the purpose of lower limb rehabilitation applications (in specific sitting/lying type of lower limb rehabilitation applications). The kinematic and dynamic model of the proposed manipulator are derived and discussed. An augmented PID control along with an uncertainty estimator is proposed for the motion control of the manipulator. The proposed system performance along with the motion controller is demonstrated numerically for the application of lower limb rehabilitation therapies using a clinically recorded gait data. The robustness of the controller and its parameter sensitivity are analysed through different operating conditions and their results are presented. Note: P—stands for Prismatic/translation joint and R—stands for Rotary/revolute joint.

The paper shows the conception of a cam workbench for educational purposes. The cam workbench aims at sustaining the learned design process and visualizing learned effects. Therefore different cams with typical transfer functions are selectable for both follower types, translating and oscillating. The properties of these cams can be analyzed by students. Besides, kinematical length of the mechanism like eccentricity and the central distance can be varied. So the students can experience the influence of the pressure angle on the complete mechanisms. In addition, the students can calculate and design their own cam. Therefore, they can practice the learned theory in exercises. The designed cams can be manufactured by 3D-printing and plugged on to the different cam shafts.

Air-jet weaving is the most productive weaving procedure. However, it is also the most energy-intensive procedure. In order to save energy newly developed high-volume-low-pressure relay nozzles can be used. The application of these nozzles requires changes in the heddle shaft movement. The design and development of a suitable mechanism to drive the heddle shaft is presented. After the determination of requirements a structural synthesis is conducted. The outcome of the structural synthesis is a set of mechanisms which in principal can solve the motion task. Subsequently a dimensional synthesis is performed to determine the kinematic parameters of each structure. The different mechanisms are then compared to each other. The most suited mechanism is a combination of a linkage and a cam mechanism. In order to improve the dynamic behavior of the heddle shaft mechanism a Fourier analysis of the shaft motion is carried out. The Fourier series of the shaft motion is then truncated and the disk cam profile is redesigned in order to drive the shaft with the desired harmonic motion. The result of the design and development process is a new heddle shaft mechanism for air-jet weaving machines with high-volume-low-pressure (HVLP) relay nozzles.

This paper introduces a modular system consisting of a 3 DOF robotic local structure with revolute joints. Several wrist joints are presented where the contact element, the end-effector, is systematically varied. The range of objects to be handled is analysed with the aim to identify a minimum of contact principles. Realizing these principles with one gripper each and defining general interfaces leads to a modular system, which warrants the versatility, flexibility and reconfigurability required for the introduced parallel handling system.

This paper presents the development of a compliant wrist joint (robotic local structure) enabling large twist angles. The result is a spherical joint with three degrees of freedom whose development is introduced starting with a general overview on suited compliant joints and the derivation of the requirements. A systematic structural synthesis and subsequently a dimensional synthesis using the pseudo-rigid-body-model is conducted. Finally, the CAD-Model is shown. The compliant robotic local structure is used in a handling system developed at the IGM facilitating a quick adaption of the kinematic structure to a new motion task through a modular and versatile concept. Several parallel kinematic robotic arms integrate an object in the kinematic structure by adapting to the object with the end-effectors.

Using geometry software within the process of mechanism development has not yet become common practice in mechanical engineering, even though in the early design stage, in which these tools are often applied, geometry software tools have a huge advantage. At this time the mechanism is not completely designed but consists of its kinematic parameters exclusively. This enables a broad analysis of a quickly generated mechanism respectively a basic synthesis for certain links of this mechanism far away from the first implementation in a CAD-system. In several mechanism lectures at IGM students were invited to familiarize with geometry software thus learning about the development of a mechanism right from the beginning. For this task the interactive geometry software Cinderella is applied, representing a freeware tool provided by Springer. But since there is a wide variety of geometry software with large differences in properties, dimensions, graphic user interface, ease of use etc., this paper presents a comprehensive comparison of common geometry software used in many different disciplines of education and later on in working life. This requires a global research into geometry software applied within the process of mechanism development. Subsequently this very long list can be split up into different groups possessing similar characteristics. Based on these characteristics an objective comparison and evaluation will be carried out. The evaluation criteria can be extracted from different show cases where a certain synthesis or analysis procedure is performed. Finally, the result of this paper is a recommendation which kind of geometry software can be efficiently applied to a present problem where a mechanism has to be developed.