New Sensor Device to Accurately Measure Cable Tension in Cable-Driven Parallel Robots

Cable-driven parallel robots are a special type of robot in which an end-effector is attached to a fixed frame by means of several cables. The position and orientation of the end-effector can be controlled by controlling the length of the cables. These robots present a wide range of advantages, and the control algorithms required have greater complexity than those in traditional serial robots. Measuring the cable tension is an important task in this type of robot as many control algorithms rely on this information. There are several well-known approaches to measure cable tension in cable robots, where a trade-off between complexity and accuracy is observed. This work presents a new device based on strain gauges to measure cable tension specially designed to be applied in cable-driven parallel robots. This device can be easily mounted on the cable near the fixed frame, allowing the cable length and orientation to change freely, while the measure is taken before the cable passes through the guiding pulleys for improved accuracy. The results obtained from the device show a strong repeatability and linearity of the measures

Cascaded Complementary Filter Architecture for Sensor Fusion in Attitude Estimation

Attitude estimation is the process of computing the orientation angles of an object with respect to a fixed frame of reference. Gyroscope, accelerometer, and magnetometer are some of the fundamental sensors used in attitude estimation. The orientation angles computed from these sensors are combined using the sensor fusion methodologies to obtain accurate estimates. The complementary filter is one of the widely adopted techniques whose performance is highly dependent on the appropriate selection of its gain parameters. This paper presents a novel cascaded architecture of the complementary filter that employs a nonlinear and linear version of the complementary filter within one framework. The nonlinear version is used to correct the gyroscope bias, while the linear version estimates the attitude angle. The significant advantage of the proposed architecture is its independence of the filter parameters, thereby avoiding tuning the filter’s gain parameters. The proposed architecture does not require any mathematical modeling of the system and is computationally inexpensive. The proposed methodology is applied to the real-world datasets, and the estimation results were found to be promising compared to the other state-of-the-art algorithms.

Plow for processing row spacing of gardens

Existing plows do not provide high-quality tillage between rows of orchards and vineyards. The purpose of the study is to develop and justify the parameters of the plow for cultivating the soil between rows of gardens to tractors of class 0.9 kN. A design scheme of a single-body plow for smooth, rowless plowing of garden aisles has been developed. The proposed plow consists of a movable and fixed frame, a disc knife, a screw body with a hostage. The research uses the laws of agricultural mechanics, mathematical statistics, and methods of strain measurement. The technology of cultivating the soil between rows of gardens with a single-body plow for smooth plowing is justified. To implement the proposed technology, the position of the plow body changes relative to the tractor during operation. It is established that when equipping a plow with a movable and fixed frame and performing a body width of 45-52. 5 cm, the required plowing quality is achieved with the lowest energy consumption.

Reflection of Light as a Mechanical Phenomenon Applied to a Particular Michelson Interferometer

Derivation of light paths in the Michelson interferometer is based on the hypothesis that the speed of light does not change after reflection by a mirror in motion. The Michelson-Morley experiment predicts a fringe shift of 0.40. The same fringe shift is predicted for a particular Michelson interferometer in which the beam splitter of the interferometer makes an angle of 45° with the direction of light from the source. Light behaves like a wave and also as a particle. Thus, it is reasonable to consider the reflection of light as a mechanical phenomenon. With this hypothesis, the speed of light changes after reflection, and the predicted fringe shift for the particular Michelson interferometer is zero which is in accordance with the result of the Michelson-Morley experiment. Apparently, light travels in any inertial frame as if this particular interferometer belongs to a fixed frame. The velocity of light is considered independent of the velocity of its source, which is in accordance with astronomers’ observations of the binary stars, and the experiment performed at CERN, Geneva, in 1964.

Actor and the sense of speech “freedom” on stage and on the screen

The subject of this research is the actor and the sense of speech “freedom” on stage and on the screen – the culture of speechification on stage and on the screen. The article raised a number of interesting questions – theatrical character, development of acting abilities depending on the type of cinematography. The author’s observations regarding speech differences in speech in movies and on stage and remarkable. Giving close attention to the use of speech elements in cinematography, the author claims that speech “impulsivities” must merge with the fixed frame. The questions of using silence in cinematography and theatre, as well as differences in its application in other spheres of art are reviewed. The conclusion is made that unlike stage actors, the diversity of voice, elocution, pace and rhythm skills of live action actors manifests functions by different laws of internal process. It is stated that speech score of stage actors is a conditionally fixed phenomenon, since stage performance is a living organism, while in cinematography, speech is more static, namely because of the do-overs and adaptation to the result desired by film director. It is underline that speech of the stage actor is strongly subordinated to rhythmic score set by text of the author, stage director, and even scenic and biological rhythms of the partner. Unlike cinematography, onstage speech is not a constant.

Dynamic wake meandering model calibration using nacelle-mounted lidar systems

Light detection and ranging (lidar) systems have gained a great importance in today's wake characteristic measurements. The aim of this measurement campaign is to track the wake meandering and in a further step to validate the wind speed deficit in the meandering frame of reference (MFR) and in the fixed frame of reference using nacelle-mounted lidar measurements. Additionally, a comparison of the measured and the modeled wake degradation in the MFR was conducted. The simulations were done with two different versions of the dynamic wake meandering (DWM) model. These versions differ only in the description of the quasi-steady wake deficit. Based on the findings from the lidar measurements, the impact of the ambient turbulence intensity on the eddy viscosity definition in the quasi-steady deficit has been investigated and, subsequently, an improved correlation function has been determined, resulting in very good conformity between the new model and the measurements.

How Motion Shapes Thought in Cinema

This article provides an embodied study of the film style of the French filmmaker Éric Rohmer. Drawing on insights from cognitive linguistics, I first show how dynamic patterns of containment shape human thinking about relationships, a concept central to Rohmer’s cinema. Second, I consider the question of how film might elicit this spatial thinking through the use of such cinematic devices as mobile framing and fixed-frame movement. Third, using Rohmer’s Comedies and Proverbs series as a case study, I demonstrate how the filmmaker applies these devices—and with them the spatial thinking they initiate—systemically to shape the relationships of his films visually. Lastly, I use the results of this analysis to provide discussion and suggestions for future research.