-The development of a humanoid robot platform within the scope of the collaborative research centre 588 has the objective of creating a machine that closely cooperates with humans. This development area presents a new challenge to designers. In contrast to industrial robots -for which mechanical rigidity, precision and high velocities are primary requirementsthe key aspects here are prevention of hazards to users, a motion space that corresponds to that of human beings and a lightweight design. In order to meet these requirements, the robot must have humanlike appearance, motion space and dexterity. Additionally, its kinematics should be familiar to the user, its motions predictable, so as to encourage inexperienced persons to interact with the machine. This article gives insight into the design of the mechatronic components of the upper body of the humanoid robot ARMAR III. Due to the special boundary conditions for the design of such a humanoid robot and complex interaction between system elements, the design process is very challenging. The robot has a modular structure. The modules for neck, torso and arms were designed and built at the Institute of Product Development (IPEK) at the University of Karlsruhe (TH). The design of these modules of the upper body and the problems solved by these designs are presented in this article.

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This work aims to facilitate the design‐improvement process of solar dryers by a computational model that accounts for the interrelationships between the conditions of the drying product (temperature and moisture content), the airflow inside the dryer (temperature, humidity, and velocity), and the surrounding conditions (temperature, humidity, and solar radiation). The model considers not only how the dryer and surrounding affect the drying of the product but also how the conditions of the product itself affect the conditions of the airflow inside the dryer and, by extension, its performance as well. To account for such intricate interrelationships, the model leverages and integrates three physical domains: fluid dynamics, heat transfer, and mass transfer. The model automatically simulates the natural convection inside the dryer and eliminates the need for obtaining the experimental values of the temperature, humidity, and velocity of the internal airflow for calculating the moisture level of the product. It can be used to quantify the effects of mixed‐mode solar dryer designs on their drying performance. Simulated results were validated against experimental data and found to be reasonably accurate. Moreover, the model offers insights into how the complex airflow inside the dryer can affect the drying of the product. Practical applications Experiments that are required to understand, compare, and improve the drying performance of different solar dryer designs can be impractical because of long operation time of solar drying and variability of weather conditions, making a typical design process time‐consuming. This work aims to facilitate the design‐improvement process. The model can quantify the effects of mixed‐mode solar dryer designs on their drying performance. The model can also offer useful insights for solar‐dryer designers. For instance, results from a case study show that the velocity and humidity of the internal airflow could have stronger influence than that of the temperature on the drying, suggesting that a solar dryer design that aims only to maximize airflow temperature may not lead to optimal drying, and that airflow temperature should not be used as the sole benchmark for solar dryer design.

Design Structure Matrix (DSM) is known as an efficient tool to modularize product architectures. It is only effective when all the matrix elements are described with a similar level of abstraction. This lies generally in the level of the real existing components. In order to implement a DSM, all assemblies, components and their relations have to be defined beforehand. In this step, the product architecture is often developed intuitively without any analysis. After the analysis using DSM, the developed product architecture normally requires rectification. Some components have to be designed and modified repeatedly. In this paper, the model for describing the relationship between function and embodiment, the Contact and Channel Model (C&CM) as well as an approach and its implementation will be presented to avoid this repetition. After a principle solution has been selected, the system is modeled with C&CM elements in a new intermediate level of abstraction. An integration analysis by DSM can be performed in parallel with the use of a search algorithm to find the modular product architecture. The analysis result is a guideline for a modular architecture which helps designers to reduce the number of required iterations. This approach is implemented in the development of a robot forearm for the humanoid robot ARMAR III.

The objective of this study was to investigate the effect of heat treatment on setting reaction and mechanical properties of tetracalcium phosphate (TTCP) and dicalcium phosphase (DCP)-based calcium phosphate cements. CPC pastes were prepared at room temperature and heated at different temperatures (from 37 to 60°C) for 10 min. Then, the preheated CPC pastes were rapidly cooled down to room temperature before further heated at 37°C until they set. Three different CPC formulations prepared from different particle sizes of TTCPs were used for the investigation. From the study, it was found that preheating could accelerate setting reaction for all CPCs according to increasing speed of hydroxyapatite (HA) conversion. The higher the preheating temperature, the faster the cements could set. However, at preheating temperature higher than 60°C longer cement setting times were observed. It may be that at high temperature some liquid content in the CPC paste evaporated, resulting in slow setting reaction rate. Compressive strengths of the cements after immersion in simulated body fluid (SBF) for 7 days increased as a result of an increase of HA conversion.