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Economic, flexible and efficient micro production needs new miniaturized automation equipment (desktop factories). Micro assembly processes make demands on precision of miniaturized robots used in desktop factories and the driving concepts, as well as miniaturized machine elements. The purpose of this paper is to investigate miniaturized drives using micro harmonic drive gears, which are promising driving concepts.

The analysis of the miniaturized precision robot Parvus (using micro harmonic drive gears) shows a good repeatability but also room for improvement concerning the path accuracy. Thereby the transmission error of the micro gears is identified as main disturbing influence concerning the robot's precision characteristics. Owing to the size reduction of the micro harmonic drive gear and the slightly different working principle compared to larger harmonic drive gears, the transmission error are more pronounced. Therefore, it is necessary to discuss approaches to compensate for this effect.

A very promising approach is the use of a simplified model of the kinematic error within the robot control to compensate for this disturbing effect. Measurement data of the transmission error is mathematically transformed into the frequency domain and filtered to the most important frequency modes of the function. These modes are used to build up a simplified mathematic model of the gear transmission error. A final test using this model as compensation function demonstrates that it is possible to reduce the transmission error of the micro gears by more than 50 percent.

The paper presents the first investigation into compensation of the transmission error of micro harmonic drive gears.

Until now, the size range of most machines for precision assembly was much larger than the size of the pieces to be handled or the necessary workspace. Flexibly scalable miniaturised production machines can help to develop much more flexible micro production systems. The paper aims to describe the development of a micro‐parallel‐SCARA robot adapted in size to MEMS products.

The robot consists of a miniaturised parallel structure, which provides a high level of accuracy in a workspace of 60 × 45 × 20 mm³. It has a base area of 130 × 170 mm² and offers four degrees of freedom.

Based on simulations, the degree of miniaturisation in terms of a smaller structure and a high level of accuracy is determined. The results show that a miniaturised hybrid robot with a plane parallel structure driven by miniaturised zero‐backlash gears and electric motors can reach a theoretical repeatability better than 1 μm.

The first prototype provides good prospects that the concept will be used in a visionary desktop‐factory. As regards the accuracy parameters of the robot, there will be further efforts to optimise the robot's structure and drive mechanism.

The repeatability of this first prototype is better than 14 μm. A better stiffness of optimised micro‐gears and joints of the structure will guarantee a much better repeatability.

The paper illustrates that the Parvus is one of the smallest industrial robots for micro assembly equipped with a full range of functionalities like conventional industrial robots.

This paper aims to provide details of miniaturised analytical instrument technologies and developments.

Following an introduction and historical background, this first considers miniaturised chromatographs and spectrometers based on micro-electromechanical system (MEMS)/micro total analytical system technologies. It then discusses lab-on-a-chip developments with an emphasis on capillary electrophoresis. Developments in the emerging lab-on-paper technology are then considered and are followed by brief concluding comments.

This shows that many classes of analytical instruments which offer a number of operational and economic benefits have been miniaturised through the use of microfabrication and other technologies. They are an active field of research and are based on silicon, glass, polymers and even paper and are underpinned by developments in microfluidics and optofluidics and fabrication techniques which include lithography, MEMS and micro-opto-electromechanical system.

This provides an insight into the rapidly developing field of miniaturised analytical instrument technologies.

This paper aims to provide an insight into recent miniaturised robot developments and applications.

Following an introduction, this article discusses the technology and applications of miniature robots and considers swarm robotics, assembly robots, flying robots and their uses in healthcare. It concludes with a brief consideration of the emerging field of nanorobotics.

This shows that all manners of miniaturised terrestrial, airborne and aquatic robots are being developed, but size and weight restraints pose considerable technological challenges, such as power sources, navigation, actuation and control. Prototypes have been developed for military, assembly, medical, environmental and other applications, as well as for furthering the understanding of swarm behaviour. In the longer term, microrobots and nanorobots offer prospects to revolutionise many aspects of healthcare, such as cancer treatment.

This study provides details of a wide-ranging selection of miniaturised robot developments.

As part of this paper, extracts will be presented from the results of the joint project “MiniProd”, which is carried out by the Fraunhofer IPA together with industrial partners and sponsored by the BMBF (Federal Ministry for Education and Research/02PD2370). The aim of the research project is to develop a marketable, miniaturized highly‐flexible micro‐assembly system capable of reproducing the correct size proportions between a product and its production environment and also able to intelligently integrate processes which had earlier run separately.

A vertically stacked, three layer hybrid Hilbert fractal geometry and serpentine radiator-based patch antenna is proposed and characterized for medical implant applications at the Industrial, Scientific and Medical band (2.4-2.48 GHz). Antenna parameters are optimised to achieve miniaturized, biocompatible and stable transmission characteristics. The paper aims to discuss these issues.

Human tissue effects on the antenna electrical characteristics were simulated with a three-layer (skin, fat and muscle) human tissue model with the dimensions of 180×70×60 mm3 (width×height×thickness mm3). Different stacked substrates are utilized for the satisfactory characteristics. Two identical radiating patches are printed on Roger 3,010 (ε _r=10.2) and Alumina (ε _r=9.4) substrate materials, respectively. In addition, various superstrate materials are considered and simulated to prevent short circuit the antenna while having a direct contact with the metallization, and achieve biocompatibility. Finally, superstrate material of Zirconia (ε _r=29) is used to achieve biocompatibility and long-life. A finite element method is used to simulate the proposed hybrid model with commercially available Ansoft HFSS software.

The antenna is miniaturized, having dimensions of 10×8.4×2 mm3 (width×height×thickness mm3). The resonance frequency of the antenna is 2.4 GHz with a bandwidth of 100 MHz at return loss (S11) of better than −10 dB characteristics. Overall, the proposed antenna have 50 Ω impedance matching, −21 dB far field antenna gain, single-plane omni-directional radiation pattern properties and incident power of 5.3 mW to adhere Specific Absorption Rate regulation limit.

Vertically stacked three layer hybrid design have miniaturized characteristics, wide bandwidth, biocompatible, and stable characteristics in three layer human tissue model make this antenna suitable for implant biomedical monitor systems. The advanced simulation analysis of the proposed design constitutes the main contribution of the paper.

The purpose of this paper is to provide a review of recent developments in miniaturised flying robots.

Following a brief consideration of micro‐ and nano‐aerial vehicles, the paper discusses recent US and European research into the development of miniaturised flying robots.

This paper shows that research into miniaturised flying robots is gaining pace and much is being funded by the US military. Two major strands of research are devices which mimic the flight dynamics of insects and living insect‐microtechnology hybrids (cyborgs). The technologies remain at an early stage of development but covert surveillance and intelligence gathering are key future applications.

The paper provides a technical review of the latest developments in miniaturised flying robots.

This paper is aimed to study the design of a miniaturized filter with tri-band characteristics. In this paper, perturbation is used to realize circuit miniaturization and multi-band by exploiting the inductive property. During this process, vias are added for twofold benefit, namely, circuit miniaturization and enhanced frequency selectivity at high frequency. Thus, with the introduction of the shorting via, the single-band dual-mode bandpass filter is converted into a tri-band filter with a smaller electrical size.

This paper presents the design and characterization of a miniaturized two-port filter with tri-band operating characteristics. The proposed filter is constructed using a square patch resonator operating at 5.2 GHz with a capacitively coupled feed configuration. A square perturbation is added to the corner of the square patch to achieve diagonal symmetry and to excite dual mode. The perturbation offers a sharp transmission zero defining bandwidth of the proposed filter. In addition, a shorting post is introduced to achieve an 88% size reduction by lowering the operating frequency to 1.8 GHz.

The prototype filter has insertion less than 1.2 dB and return loss better than 12 dB throughout all the realized frequency bands. The prototype filter is fabricated and the simulation results are validated using experimental measurements. The realized fractional bandwidths of the proposed bandpass filter are 11/5.6/1 at 1.8/4.6/5.85 GHz, respectively. The quality factor of the proposed antenna is greater than 80 and a peak Q-factor of 387 is realized at 5.85 GHz. The high Q-factor indicates low loss and improved selectivity. The rejection levels in the stopband are greater than 20 dB.

The results indicate that the proposed filter is a suitable choice for low-power small-scale wireless systems operating in the microwave bands. The realized filter has the smallest footprint of 0.36λ_eff  × 0.19λ_eff where λ_eff is the effective wavelength calculated at the lowest frequency of operation.

Aims to discuss how a Cartesian parallel robot with flexure revolute joints can effectively perform miniaturized assembly tasks.

The results of the test and validation phase of a Cartesian parallel robot designed for miniaturized assembly are shown. The workspace volume is a cube with 30 mm side and the target accuracy is 1 μm. Each of the three robot legs has a prismatic‐planar architecture, with a cog‐free linear motor and a planar joint realized using ten superelastic flexure revolute joints. Flexure joints are adopted in order to avoid stick‐slip phenomena and reach high positioning accuracy; their patented construction is relatively low‐cost and allows a quick replacement in case of fatigue failure.

The tests on the prototype are very encouraging: the measured positioning accuracy of the linear motors is ±0.5 μm; on the other hand, the effects of unwanted rotations of flexure joints and hysteresis of the superelastic material are not negligible and must be properly compensated for in order to fully exploit the potential performance of the machine.

The introduction of this robotic architecture can fulfil the needs of a wide range of industrial miniaturized assembly applications, thanks to its accurate positioning in a relatively large workspace. The cost of the machine is low thanks to its extreme modularity.

The combination of Cartesian parallel kinematics, cog‐free linear motors and superelastic flexure revolute joints allows one to obtain very good positioning performance.

This study aims to investigate the effect of the wall thickness, deposition orientation and two different post-processing methods on the local mechanical properties and microstructure of additively manufactured parts made of maraging steel. In order to examine the local properties of the build, miniaturized testing specimens were employed. Before application of small-sized specimens, their performance was verified.

The investigation was composed of two stages. As first, the part thickness, specimen size and orientation were studied on a laser-powder bed fusion (L-PBF) platform with deposited walls of various thicknesses made of maraging steel. Subsequently, the influence of different heat-treatment methods was investigated on the final product, i.e. impellers. The miniaturized and standard tensile tests were performed to investigate the local mechanical properties. The porosity, microstructures and fracture surfaces were analysed by X-ray-computed tomography, X-ray diffraction and scanning electron microscopy with electron backscatter diffraction.

The results revealed good agreement between the values provided by miniaturized and standard specimens. The thinnest parts produced had the largest pores and the highest scatter of elongation values. In these cases, also the sub-contour porosity was observed. Part thickness affected pores’ size and results repeatability but not total porosity. The two-step heat-treatment (solutionizing and age-hardening) exhibited the highest yield and ultimate tensile strength.

The microstructure and local mechanical properties were studied on L-PBF platform with deposited walls of various thicknesses. Subsequently, a detailed analysis was conducted on real components (impellers) made of maraging steel, commonly used in tooling, automotive and aerospace industries.

The broadly understood quality of manufactured parts is crucial for their reliable and long-lasting operation. The findings presented in the manuscript allow the readers better understanding of the connection between deposition parameters, post-processing, microstructure and mechanical performance of additive manufacturing-processed parts.