Rotational Part Research Articles

Classical-relativistic variability of inertia of photon displacement mass in the matter and the specific vacuum temperature

The effects of photon inertia on the determination of its trajectory were verified and the representation of a displacement mass characterized by the flow of the number of wavefronts and the decomposition of photon inertia into parts associated with translation and rotation motions was considered. It was found that with the relativistic increase of the photon's resistance to change its directional properties, it inhibits the relativistic trajectory of the second torque, so called Minkowski torque, in an angular range of incidence. After synchronizations, in the OAM inversions, there are reductions of the inertia associated to the translational part that assumes classical predominance, where the relativistic trajectory is allowed while the photon offers less resistance to changes in its directional properties. The classical-relativistic variability of the photon inertia characterizes the classical or relativistic profile of the energy distribution in forms of motion, where adjustments of the rotational and translational parts can be performed as a function of the refractive index rate, temperature and angle of incidence. It was found that with increasing temperature of the refringent medium, the synchronizations displacement in the sense of the normal incidence. A specific vacuum temperature for the refringent medium was characterized, where the photon exhibits a classical-relativistic synchronization under all angles of incidence, characteristic of its immaterial state in vacuum.

Accurate Real-Time Temperature Measurement Method in Ultra-High Temperature Rotational Environments for Aero Engines/Turbines

This study proposes an innovative method to wirelessly measure the ultra-high temperatures of rotational parts in aero-engines/turbines. The upper measurement limit of this proposed sensor is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1100 ^\circ \text{C}$ </tex-math></inline-formula> . Based on the thick film integration process, the inductor and capacitor are integrated in-situ on the ceramic turntable and ceramic blade. The inductor and capacitor operate in the high temperature and ultra-high temperature areas, respectively, and the temperature signal is transmitted through the electromagnetic coupling between the inductor coil and the antenna. The design of the structure separating the capacitor and inductors is important and can improve the sensor’s high temperature signal reading performance. The designed sensor is tested in the temperature range of 25– <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1100 ^\circ \text{C}$ </tex-math></inline-formula> and the rotational speed range of 0–400 rpm. The results show that the minimum sensitivity of the sensor at different rotational speeds is 7.66 kHz/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^\circ \text{C}$ </tex-math></inline-formula> , and the minimum sensitivity of the sensor at different rotational speeds is 7.83 kHz/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^\circ \text{C}$ </tex-math></inline-formula> . The maximum standard deviation and repeatability of the sensor measured across different temperatures and rotational speeds are 0.11(400 rpm, 900 °C)and 0.389%(400 rpm, 900 °C), respectively. The interference of the rotational speed on the temperature test of the sensor is negligible. The experimental results show that the sensor has strong signal strength in ultra-high temperature rotational environments and is suitable for ultra-high temperature testing.

Fluidic system with movable layers for all-in-one assay of cell-free DNA in blood

Detection of circulating cell-free DNA (cfDNA) requires multiple processes, including plasma separation, cfDNA isolation, and high-sensitivity detection. However, implementing such processes in a single system in a simple and effective manner is nontrivial. Here, we present a fluidic system for the isolation and detection of cfDNA from whole blood performed in a fully automated and effective manner. The system utilizes vertically mobile top and rotational bottom parts with multiple disposable chambers for sequential processes. The key components for plasma filtration are a sedimentation chamber that enables the dextran-enhanced sedimentation of red blood cells and a plunger chamber with a porous filter and a check valve. cfDNA in the plasma is captured by silica-coated magnetic beads in the plunger chamber, washed via the motion of the top and bottom parts, and then detected by real-time on-chip polymerase chain reaction. We vary several parameters, including the plunger speed, dextran concentration, and hematocrit concentration, to optimize the time and efficiency of the assay. The total assay time is 1.5 h with a detection limit of 42 ag/mL for a sample volume of 1.5 mL. Plasma and cfDNA recoveries are 53% and 28%, respectively. Our system is a useful tool for all-in-one assays in liquid biopsies of cancers and other diseases detectable by cfDNA.

How Does Crop Rotation Influence Soil Moisture, Mineral Nitrogen, and Nitrogen Use Efficiency?

Rice–wheat (RW) cropping systems are integral to global food security. Despite being practiced for decades, Chinese RW cropping systems often suffer from low productivity and poor nitrogen use efficiency (NUE), reflecting management approaches that are not well-contextualized to region and season. Here, we develop the best management guides for N fertilizer in RW systems that are designed to help raise the productivity, NUE, and environmental sustainability of winter wheat over the long term. 2-year field experiments were conducted with four N fertilizer rates (0, 135, 180, and 225 kg N ha–1), allowing contrasts of yields, soil moisture, and NUE of wheat in RW in the humid climates zones on the Jianghan Plain. We compared RW systems with soybean/maize dryland wheat (DW) systems that are similarly endemic to China: after soybean/maize is harvested, soils are often drier compared with moisture content following rice harvest. With high seasonal N application rates (180–225 kg N ha–1), wheat crop yields increased by 24% in RW which were greater than comparable yields of wheat in DW, mainly due to greater kernels per spike in the former. Across treatments and years, N accumulation in plant tissue and kernel dry matter of DW was higher than that in RW, although mean agronomic efficiency of nitrogen (AEN) and physiological efficiency of nitrogen (PEN) of RW systems were greater. As N application rates increased from 135 to 225 kg ha–1, AEN and PEN of DW decreased but changed little for RW. Soil ammonium N was much lower than that of nitrate N; changes in NH4+ and NO3– as a consequence of increasing N fertilization were similar for RW and DW. We recommend that tactical application of N fertilizer continue seasonally until midgrain filling for both the DW and RW systems. At fertilization rates above 180 kg N ha–1, yield responses disappeared but nitrate leaching increased significantly, suggesting declining environmental sustainability above this N ceiling threshold. Collectively, this study elicits many functional and agronomic trade-offs between yields, NUE, and environmental sustainability as a function of N fertilization. Our results show that yield and NUE responses measured as part of crop rotations are both more robust and more variable when derived over multiple seasons, management conditions, and sites.

On the time of existence of solutions of the Euler–Korteweg system

The Euler–Korteweg system is a dispersive perturbation of the usual compressible Euler equations. In dimension at least three, under a natural stability condition on the pressure, the author proved with B. Haspot that the Cauchy problem is globally well-posed for small, smooth, irrotational initial data. As a continuation of this work, we prove that if the initial velocity has a small rotational part, there exists a lower bound on the time of existence that depends only on some norm of this rotational part. In the zero vorticity limit we recover the previous global well-posedness result.

Numerical simulation of cyclic shear tests considering the fabric change and principal stress rotation effects

AbstractCyclic loadings could induce complicated soil responses, including the fabric change and principal stress rotation, both of which would reduce the effective confining pressure and accelerate the build‐up of excess pore water pressures, thus leading to sand liquefaction in undrained conditions. The principal stress rotation, even without the change of principal stress magnitudes, would further generate the accumulative plastic shear strains. However, most of the existing studies focus on their individual effect and the combined effect was seldom considered. In this paper, a numerical approach including an elastoplastic sand constitutive model is proposed to consider the combined effect of the fabric change and principal stress rotation. In this model, the fabric change is considered with the anisotropic critical state theory and the principal stress rotation is considered by splitting the plastic strain increment into the monotonic part and rotational part. By simulating a series of cyclic shear tests, results from the numerical solutions are found showing good agreements with the existing experimental results and the importance of considering the combined effect is demonstrated. The approach can be used to predict the stress‐strain response of sand and guide the design of foundations especially in undrained cyclic loading conditions, for example, earthquake loadings conditions.

An Image Registration Model in Electron Backscatter Diffraction

Recently, variational methods were successfully applied for computing the optical flow in gray and RGB-valued image sequences. A crucial assumption in these models is that pixel-values do not change under transformations. Nowadays, modern image acquisition techniques such as electron backscatter tomography (EBSD), which is used in material sciences, can capture images with values in nonlinear spaces. Here, the image values belong to the quotient space $\text{SO}(3)/ \mathcal S$ of the special orthogonal group modulo the discrete symmetry group of the crystal. For such data, the assumption that pixel-values remain unchanged under transformations appears to be no longer valid. Hence, we propose a variational model for determining the optical flow in $\text{SO}(3)/\mathcal S$-valued image sequences, taking the dependence of pixel-values on the transformation into account. More precisely, the data is transformed according to the rotation part in the polar decomposition of the Jacobian of the transformation. To model non-smooth transformations without obtaining so-called staircasing effects, we propose to use a total generalized variation like prior. Then, we prove existence of a minimizer for our model and explain how it can be discretized and minimized by a primal-dual algorithm. Numerical examples illustrate the performance of our method.

Optimal robot-world and hand-eye calibration with rotation and translation coupling

AbstractA classic hand-eye system involves hand-eye calibration and robot-world and hand-eye calibration. Insofar as hand-eye calibration can solve only hand-eye transformation, this study aims to determine the robot-world and hand-eye transformations simultaneously based on the robot-world and hand-eye equation. According to whether the rotation part and the translation part of the equation are decoupled, the methods can be divided into separable solutions and simultaneous solutions. The separable solutions solve the rotation part before solving the translation part, so the estimated errors of the rotation will be transferred to the translation. In this study, a method was proposed for calculation with rotation and translation coupling; a closed-form solution based on Kronecker product and an iterative solution based on the Gauss–Newton algorithm were involved. The feasibility was further tested using simulated data and real data, and the superiority was verified by comparison with the results obtained by the available method. Finally, we improved a method that can solve the singularity problem caused by the parameterization of the rotation matrix, which can be widely used in the robot-world and hand-eye calibration. The results show that the prediction errors of rotation and translation based on the proposed method be reduced to $0.26^\circ$ and $1.67$ mm, respectively.

On the elastic wedge problem within simplified and incomplete strain gradient elasticity theories

In this paper, we investigate the behavior of the strain gradient elasticity solutions around the sharp edges of the body loaded by the concentrated loads. We consider the general Mindlin–Toupin strain gradient elasticity (SGET) and several simplified models, including the dilatation gradient elasticity theory (DGET) and the couple stress theory (CST). In the framework of a plane strain problem for an elastic wedge with prescribed tip displacement we obtain analytical assessments for the displacement field and the stress state around the wedge apex. Involving the Papkovich–Neuber solution we show that the nonsingular solutions for this problem can be obtained within the general SGET and within simplified gradient models that provide the regularization of the dilatational and the rotational parts of the displacement field both. In the incomplete theories such as DGET or CST the singularity in the displacements and stresses at the wedge apex cannot be avoided. This result is validated also based on the full-field numerical solutions for the wedge-type domains. It is shown that the stress field around the wedge apex is bounded in the complete gradient theories, while the mesh dependent solutions are realized in DGET and CST. Generally, obtained results means that the boundary value problems with the edge-type loading should be abandoned within the incomplete gradient theories like DGET and CST or it can be considered only under some additional assumptions (similarly to classical elasticity).

Phytoprevention of Heavy Metal Contamination From Terrestrial Enhanced Weathering: Can Plants Save the Day?

Enhanced weathering is a promising approach to remove carbon dioxide from the atmosphere. However, it may also pose environmental risks through the release of heavy metals, in particular nickel and chromium. In this perspective article I explore the potential role of plants in modulating these heavy metal fluxes. Agricultural basaltic soils may be valuable study sites in this context. However, the effect of biomass harvesting on the accumulation of heavy metals is currently not well studied. Mostly caused by different parent rock concentrations, there is a large variability of heavy metal concentrations in basaltic and ultramafic soils. Hence, to minimize environmental risks of enhanced weathering, basalts with low heavy metal concentrations should be favored. Existing phytoremediation strategies may be used to “phytoprevent” the accumulation of nickel and chromium released from enhanced weathering in soils. As a result, elevated nickel and chromium concentrations in rocks must not preclude enhanced weathering in all settings. In particular, hyperaccumulating plants could be used as part of a crop rotation to periodically remove heavy metals from soils. Enhanced weathering could also be employed on fields or forests of (non-hyper) accumulating plants that have a high primary production of biomass. Both approaches may have additional synergies with phytomining or bioenergy carbon capture and storage, increasing the total amount of carbon dioxide drawdown and at the same time preventing heavy metal accumulation in soils.

Thermal, Mechanical, Morphological and Aesthetical Properties of Rotational Molding PE/Pine Wood Sawdust Composites.

This research addresses the importance of pine wood sawdust granulometry on the processing of medium-density polyethylene (MDPE)/wood composites by rotational molding and its effects on the morphological, mechanical and aesthetical properties of parts, aiming to contribute for the development of sustainable wood polymer composites (WPC) for rotational molding applications. Pine wood sawdust was sieved (<150, 150, 300, 500, 710, >1000 µm) and analyzed for its physical, morphological and thermal characteristics. Rotational molded parts were produced with matrix/wood ratios from 90/10 to 70/30 wt% considering different wood granulometries. As a natural material, wood changed its color during processing. Granulometries below 500 µm presented better sintering, homogeneity and less part defects. Furthermore, 300–500 µm favored the impact resistance (1316 N), as irregular brick-shaped wood was able to anchor to PE despite the weak interfacial adhesion observed. The increase of wood content from 10 to 30% reduced the impact properties by 40%, as a result of a highly porous structure formed, revealing sintering difficulties during processing. WPC parts of differentiated aesthetics and functionalities were achieved by rotational molding. A clear relationship between wood granulometry and WPC processing, structure and properties was identified.

ВЛИЯНИЕ АГРОМЕТЕОРОЛОГИЧЕСКИХ УСЛОВИЙ НА СОРНЫЙ КОМПОНЕНТ В АГРОЦЕНОЗЕ ОЗИМОЙ ПШЕНИЦЫ В ПРЕДГОРНОЙ ЗОНЕ РСО – АЛАНИЯ

Weeds are an ecological group of plants that has developed as a result of their growth together with cultivated plants in the process of continuous struggle with them. In order to successfully fight weeds, it is necessary to know their biological characteristics, classification, distribution and reproduction of weeds. The number of weeds does not always reflect the degree of their harmfulness, since it is largely determined by the power of development of the above-ground mass of weeds. Different types of weeds react differently to changes in the level of fertilizer, the method of basic tillage, the structure of crops and the rotation of crops in crop rotation. The advantage is given to those species for which all these changes are favorable and contribute to their growth, development and distribution in phytocenoses. In addition to them, weed species that have endurance and resistance to adverse environmental factors survive and maintain their population density. According to many scientists, the mass and number of weeds reflect different aspects of relationships in the community. The number shows the interaction in the surface layer of the soil, at a low altitude, as well as in the initial phases of development, and the mass of the weed component characterizes the coenotic relationships in the middle and upper tiers at later stages of development. The purpose of our research was the influence of agrometeorological conditions on the species composition, abundance, dry biomass and the ratio of biological and ecological groups of weeds in the winter wheat agrocenosis. Our research was carried out in 2017–2021. on the experimental experimental field of the SKNIIGPSh VSC RAS in the forest-steppe zone of the North Ossetia - Alania. The object of research was winter wheat variety Trio. The plot area is 100 m², repeated three times. This crop was part of a five-field soil-protective crop rotation. We have found that in the forest-steppe zone of North Ossetia - Alania, agrometeorological conditions largely affect the species composition, abundance and biomass of harmful weeds.

ПРИМЕНЕНИЕ РЕГУЛЯТОРА РОСТА НА ПОСЕВАХ ОЗИМОЙ ПШЕНИЦЫ ЛЕСОСТЕПНОЙ ЗОНЫ РЕСПУБЛИКИ СЕВЕРНАЯ ОСЕТИЯ – АЛАНИЯ

Weeds are an ecological group of plants that has developed as a result of their growth together with cultivated plants in the process of continuous struggle with them. In order to successfully fight weeds, it is necessary to know their biological characteristics, classification, distribution and reproduction of weeds. The number of weeds does not always reflect the degree of their harmfulness, since it is largely determined by the power of development of the above-ground mass of weeds. Different types of weeds react differently to changes in the level of fertilizer, the method of basic tillage, the structure of crops and the rotation of crops in crop rotation. The advantage is given to those species for which all these changes are favorable and contribute to their growth, development and distribution in phytocenoses. In addition to them, weed species that have endurance and resistance to adverse environmental factors survive and maintain their population density. According to many scientists, the mass and number of weeds reflect different aspects of relationships in the community. The number shows the interaction in the surface layer of the soil, at a low altitude, as well as in the initial phases of development, and the mass of the weed component characterizes the coenotic relationships in the middle and upper tiers at later stages of development. The purpose of our research was the influence of agrometeorological conditions on the species composition, abundance, dry biomass and the ratio of biological and ecological groups of weeds in the winter wheat agrocenosis. Our research was carried out in 2017–2021. on the experimental experimental field of the SKNIIGPSh VSC RAS in the forest-steppe zone of North Ossetia - Alania The object of research was winter wheat variety Trio. The plot area is 100 m², repeated three times. This crop was part of a five-field soil-protective crop rotation. We have found that in the forest-steppe zone of North Ossetia - Alania, agrometeorological conditions largely affect the species composition, abundance and biomass of harmful weeds.

Simulation calculation of temperature field of gearbox in straddle monorail train

For a straddle-type monorail train gearbox, analyze the heating mechanism and heat transfer mode of each element in the gearbox, establish a heat transfer model of the gearbox, use empirical formula to calculate the heating power of each heating element, and use the flow field analysis to monitor it. Accurately calculate the convective heat transfer coefficient for the volume fraction of oil and gas in each cavity. Using the method of finite element simulation, the influence of different oil injection and large spiral bevel gear steering on the temperature field distribution of the gearbox is calculated and analyzed. The results show that when the large spiral bevel gear turns for a certain amount of time, the maximum temperature of each part of the gearbox at high oil level is higher than that at low oil level; When the amount of oil injection is constant, the temperature of each part in the reverse rotation of the large spiral bevel gear is higher than that in the forward rotation. This article provides the main reference for the prediction of the temperature field of the gearbox of the straddle monorail train and the improved design of the lubricating oil passage in the gearbox.

Adjusting systematic bias in high dimensional principal component scores

Principal component analysis continues to be a powerful tool in dimension reduction of high dimensional data. We assume a variance-diverging model and use the high-dimension, low-sample-size asymptotics to show that even though the principal component directions are not consistent, the sample and prediction principal component scores can be useful in revealing the population structure. We further show that these scores are biased, and the bias is asymptotically decomposed into rotation and scaling parts. We propose methods of bias-adjustment that are shown to be consistent and work well in the high dimensional situations with small sample sizes. The potential advantage of bias-adjustment is demonstrated in a classification setting.

RESEARCH REGARDING THE INFLUENCE OF NITROGEN AND PHOSPHORUS FERTILIZERS ON WINTER WHEAT, IN THE PEDOCLIMATIC CONDITIONS IN CENTRAL OF MOLDAVIA

Winter wheat is one of the agricultural plants that reacts positively to the application of fertilizers in all soil and climatic conditions in our country. Factors that influence the effectiveness of fertilizers and create dosing difficulties, require the organization of a certain long-term experience for complex research of complex interactions plant x soil x fertilizer x climate and their effect on plant productivity, established in Secuieni in 1975. This paper presents the results obtained in a long-term experience with chemical fertilizers (NP) in winter wheat crop, located in Agricultural Research and Development Station Secuieni Neamț (A.R.D.S. Secuieni, Neamț), during 2019-2021. The experience takes place in the experimental field of the unit, on a typical cambic faeoziom (chernozem) soil, with medium texture, and its an bifactorial type (N x P) and were placed according to the method of subdivided plots, in five repetitions: the factor A phosphorus, with the following graduations: P0, P40, P80, P120 and P160 and factor B nitrogen, with the following graduations: N0, N40, N80, N120 and N160. The winter wheat culture is part of a three-year crop rotation with beans – winter wheat - corn. Following in rotation after beans, no nitrogen fertilizers were applied at the establishment of the crop. The variety studied is the Glosa variety, created at N.A.R.D.I. Fundulea (National Institute for Agricultural Research and Development Fundulea). In the climatic conditions of the two experimental years (2019-2021) the yields obtained from the application of chemical fertilizers varied depending on the applied dose. In the first year of testing, the yield varied in very high limits, from 3232kg ha-1 in the non-fertilized version and up to 6525 kg ha-1 in the version fertilized with N120P80. In the second year, the minimum yield was obtained in the version in which no fertilizer was applied dose, of 6133 kg ha-1, and the variant in which the fertilizer doses of N120P120 were applied obtained the highest yield, of 9429 kg ha-1. On average, the factors studied greatly influenced winter wheat yield, which variet within large limits, between 4683 kg ha-1 (N0P0) and 7787 kg ha-1 (N120P120).

Objectives and Structure of the Information and Communication System for "Smart" Organic Farming

The authors showed that the organic production is an actively growing global business: in 2017, it occupied more than 1.4 percent of all agricultural land on the planet. The authors emphasized the relevance of digitalization with the constant growth of the database, which the farmer needs to process quickly and effi ciently. (Research purpose) To form the structure of the information and communication system for the «smart» crop organic farming and the database necessary for its training and ensuring its functioning. (Materials and methods) The prior research was used, as well as previously created databases and information from the existing literature. Since 2016, a multifactorial experiment with potatoes has been carried out as part of an organic crop rotation to fi ll the information base with experimental data. (Results and discussion) The structure of the information and communication system of the “smart” organic crop production has been formed. It is based on the territory digital map and agricultural crop digital models. In the course of the work of the system, we decided to make daily changes to the digital model of agricultural crops based on the incoming agroecological information, as well as to prepare recommendations on the relevant choice and use of the planned technological operations. It was found out that in a fouryear fi eld experiment, the potato yield in the control variant (without the introduction of compost and pesticides) averaged 21.7 tons per hectare, and when using compost and biofungicide Kartofi n, it increased to 26.7 tons per hectare. The authors calculated multiple linear regression equations describing the dependence of the nitrogen mineral form content in the soil in June on the sum of the active temperatures during this period and the compost dose (the correlation coeffi cient is 0.658); and the dependence of potato yield on the nitrogen mineral form content in the soil in the fi rst ten days of June and the sum of active temperatures in May-June (the correlation coeffi cient is 0.667). (Conclusions) The authors presented the structure of the information and communication system of an organic agricultural enterprise, substantiated the possibility of its full implementation as a tool that helps agricultural producers to carry out environmentally safe, competitive and effi cient organic production at a totally new level.

Failure Prediction of Wind Turbine using Neural Network and Operation Signal

This paper deals with a novel prediction method for wind turbine by using neural network and operating data. As wind turbine transfer wind energy to electrical power energy, its structure has rotation part that capture wind energy, mechanical part, and electrical part that convert from mechanical rotation to electrical energy. Its working environmental situation is so bad like high mountain, sand desert, and offshore to capture good wind situation. Therefore, its control and monitoring should have high reliability for long terms during operation because its maintenance and repairing is very difficult and economically high cost. As wind turbine system is composed of three parts, there are many components that should be monitored to failure. This paper suggests neural network and operation data-based prediction method that can predict components' failure through data comparison and neural network's training function with easy expression of 'Yes' or 'No' for operator.

A Low-Sidelobe-Level Variable Inclination Continuous Transverse Stub Antenna with a Nonlinear Slow-Wave Structure

The sidelobe level (SLL) is an essential performance factor for satellite communication antennas. A low-SLL design can effectively suppress adjacent satellite interference. A low-SLL design method for a variable inclination continuous transverse stub (VICTS) antenna is proposed in this paper. The VICTS antenna is composed of three rotatable parts: a feeding plate, a radiation plate, and a polarization plate. The radiation plate comprises two groups of stubs with different radiation ratios. Combined with the nonlinear slow-wave structure attached to the feeding plate, the radiation ratio of the unit can be adjusted. The aperture field of the VICTS antenna using this method can be tapered in order to suppress the SLL. To verify the effectiveness of this method, the antenna prototype is fabricated and measured in a microwave anechoic chamber. The simulation and the measurement are in good agreement. The reflection coefficient of the antenna is kept below −15 dB and between 13.75 GHz and 14.5 GHz. When the radiation plate and the feeding plate rotate relative to each other, the pattern beam can be scanned from 5° to 70 ° . In the scanning range, the typical SLL can reach −18 dB.

Demonstrating Tangential Velocity by a Self-Coded Robot

Tangential velocity is a concept that is often taught as a part of rotation, and is the linear velocity an object has as it turns about a fixed axis. The main goal of this research project was to examine this concept and demonstrate it on a self-coded robot. The robot was designed with two rotating motors with two wings of different lengths to be attached on top, and the motors were connected to a circuit board and coded using the programming language C to rotate with equal and constant angular velocities upon initiation. The main hypothesis is that the length of rotating wings is directly proportional to the tangential velocity of the wings. The project provides a new way of demonstrating tangential velocity in a high school physics class.