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Outlines research work on the control of flexible single‐link robot arms in which the link is modelled as a beam and the end‐point position is controlled by measuring that position and using that measurement as a basis for applying a torque to the link joint. A position sensor device [PSD] is used as the measuring device. Describes how the measurement is taken and explains the measurement circuit and how the links are analyzed. Concludes that the simplicity of the general configuration of the photosensor system and the nature of the direct data obtained allows it to be used in a wide range of applications.

The purpose of this paper is to present a new device (thermoelastic actuator) for accurate control of position whose principle is based on thermal dilatation of its working unit brought about by induction heating.

The device must satisfy the prescribed operation parameters (mainly the above thermal dilatation). The task to find them is a multiply coupled problem (interaction of electromagnetic field, temperature field and field of thermoelastic displacements) that is solved by the finite element method supplemented with a number of other procedures.

The control of position based on the described thermoelastic effect is very accurate and ranges from 1×10⁻⁶ to 1×10⁻³ m.

The device also contains two self‐locking friction clutches of conical shapes whose purpose is to fix the position of the plunger in the prescribed position. Further attention should be paid to their dynamic behaviour during the process of fixing.

The device can be used in various technical domains such as optics and laser or microscope techniques.

The principal part of the device contains no movable element, which is a substantial advantage in comparison to other systems based on mechanical, hydraulic or pneumatic principles working with movable elements or media.

Sensors considerably increase the new applications of industrial robots. Assembly utilizations exist in the fields of part loading, the supervision of the gripping and part mating process, and tolerance compensation as well as the testing and checking of the assembly job. A couple of years ago sensor applications in assembly with industrial robots existed only in research laboratories and development institutions. Nowadays, industry cannot refuse to use them. Improvements on sensorics such as faster data processing and lower costs, as well as higher accuracies in measuring and a more favourable rate to price and efficiency, allow sensor guided robots in assembly with technical and economical significance. Assembly systems with industrial robots demand high flexibility, process supervision and control to increase output quality, and require manifold sensor utilizations.

The purpose of this study was to investigate the performance of a single-bridge ZnO nanorod as a photodetector.

The fabrication of the design sensor with ∼6-μm gap Schottky contacts and bridging of the ZnO nanorod were based on conventional photolithography and wet-etching technique. Prior to bridging, the ZnO nanorods were grown by the hydrothermal process. The 0.35 M seed solution was prepared by dissolving zinc acetate dihydrate in 2-methoxyethanol, and monoethanolamine, which acts as a stabilizer, was added drop-wise. Before starting the solution deposition, and oxide, titanium (Ti) and gold (Au) layer deposition, p-type (100) silicon substrate was cleaned with Radio Corporation of America (RCA1) and RCA2, followed by dipping in diluted hydrofluoric acid. The aged solution was dropped onto the surface of the Au microgap structure, using a spin coater at a spinning speed of 3,000 rpm for 45 seconds, and then dried at 300°C for 15 minutes, followed by annealing at 400°C for 1 hour. The hydrothermal growth was carried out in an aqueous solution of zinc nitrate hexahydrate (0.025 M) and hexamethyltetramine (0.025 M).

In this study, ZnO nanorods were grown on a SiO₂ substrate by the hydrothermal method. Microgap electrodes with ∼6-μm spacing were achieved by using the wet-etching process. After the growth process, an area-selective mask was utilized to reduce the number of rods between the nearby gap areas. The obtained single ZnO nanorod was tested for the UV-sensing application. The single ZnO nanorod photodetector exhibited a UV photoresponse, thereby indicating potential as a cost-effective UV detector. The response and recovery times of the fabricated device were 65 and 95 seconds, respectively. Structural analysis was captured using X-ray Diffraction (XRD), whereas surface morphology was determined using scanning electron microscopy.

This paper demonstrates the effect of UV photon on a single-bridge ZnO nanorod between microgap electrodes.

The purpose of this paper is to study the spectral sensitivity characteristics of new pyroelectric sensor based on tetraaminodiphenyl film within the wavelength range of 0.4-10 µm and 300-3,000 µm.

Mylar film with the thickness of about 70 µm was used as the input window. The MDR-41 monochromator-based spectrometric complex and the quasi-optical spectrometer with the set of backward-wave oscillators were used for measurements of the pyrodetector spectral characteristics within the 0.4-10 µm and 300-3,000 µm ranges, respectively.

Mylar was found to have absorption lines within the range of 0.4-10 µm, which must be taken into account when broadband detectors developing. The noise equivalent power in the visible and infrared ranges was less than 6 × 10^–10 W/Hz^1/2, which is about five times lower than for analogue ones. In the sub-THz range, the pyrodetector sensitivity is 2-8 times higher than the Golay cell. The sensitivity of such pyrodetector weakly depends on the wavelength in the total measured range.

The pyroelectric sensor has good prospects for use in super wide spectral range, from ultraviolet to millimeter radiation, in spectrometers for scientific research, in industry for the operational control of THz radiation sources, as well as in security THz-systems.

The spectral sensitivity characteristics of the pyroelectric photosensor based on TADPh in the visible, infrared and terahertz ranges were measured. The prospects for the use of such sensors were determined.

This study aims to investigate photosensing characteristics of SiC and GaN nanowire-based devices through exposure to UV light. The photocurrent transients have been modeled to determine rise and decay process time constants. The 1D-semiconductor nanowires can exhibit higher light sensitivity compared to bulk materials because of their large surface area to volume ratio and the quantum size effects.

Nanowire devices have been fabricated through dielectrophoresis for integrating nanowires onto pre-patterned electrodes (10 nm Ti/ 90 nm Au) with a spacing about 3 µm onto SiO₂/Si (doped) substrate. The photocurrent measurements were carried out under room temperature conditions with UV light of 254 nm wavelength.

SiCNWs yield very short rise and decay time constants of 1.3 and 2.35 s, respectively. This fast response indicates an enhanced surface recombination of photoexcited electron-hole pairs. Conversely, GaNNWs yield longer rise and decay time constants of 10.3 and 15.4 s, respectively. This persistent photocurrent suggests a reduced surface recombination process for the GaNNWs.

High selective UV light sensitivity, small size, very short response time, low power consumption and high efficiency are the most important features of nanowire-based devices for new and superior applications in photodetectors, photovoltaics, optical switches, image sensors and biological and chemical sensing.

The purpose of this study is to construct imaging pixels using novel bioactive films. Despite the notable progress in electronic imaging devices, these sensors still cannot compete with biological vision counterparts such as the human eye. Light sensitive biolayers and pigments in living organisms show superior performance in terms of low noise operation and speed. Although photoactive biolayers have been used to construct electronic imaging devices, they are usually hard to develop, and the organisms that produce these active layers have low growth rates.

Among 40 pigment producing prokaryotic marine bacteria, four strains which show faster growth rates in the presence of light are screened and characterized by Fourier transform infrared spectroscopy and visible absorption. Subsequently, they are used as active layers in light sensitive sensors. The performance of the obtained cells is eventually evaluated by time domain photoresponse measurements.

It is shown that while the obtained strains have high growth rates and their mass volume reproduction is relatively simple, they provide many interesting characteristics such as high speed and low noise operation when incorporated as photosensitive layers.

Because the mass reproduction of the obtained cultures is simple, they are an appropriate choice for use in planner and flexible document imaging devices and DNA microarray sensors.

Various types of sensors such as tactile, proximity and visual, have been developed to give robots flexibility and adaptability. It is argued that for complex tasks the individual sensors need to be integrated into a total system. In this article a variety of sensors developed by the authors are presented as modules and a design approach for a total system is discussed.

SIGNIFICANT strides have been made in the development of advanced electrically‐suspended inertial components and systems capable of utilizing them. At Honeywell, considerable contract support by both the United States Navy and the United States Air Force, in addition to Company‐sponsored effort, has resulted in Electrically‐Suspended Gyros that have achieved accuracies of one or two orders of magnitude better than those of the best conventional gyros.

This article examines the various methods available for the measurement . of distance using light. These can vary considerably in price and performance and therefore an understanding of the capabilities of a range of systems and techniques is useful so that the most appropriate choice for a given application can be made.