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This study introduces a technique for determining surface orientations by projecting a monochrome, spatial pixel-encoded pattern and calculating the surface normals from single-shot measurement. Our method differs from traditional methods, such as shape from shading and shape from texture, in that it does not require relating the local surface orientations of adjacent points. We propose a multi-resolution system incorporating symbols varying in sizes from 8 × 8, 10 × 10, 12 × 12, 14 × 14, and 16 × 16 pixels. Compared to previous methods, we have achieved a denser reconstruction and obtained a 5.2 mm resolution using an 8 × 8 pattern at a depth of 110 cm. Unlike previous methods, which used local point orientations of grid intersection and multiple colors, we have used the monochrome pattern and deterministic centroid positions to compute the unit vector or direction vector between the neighboring symbols. The light plane intersections are used to calculate the tangent vectors on the surface. Surface normals are determined by the cross-product of two tangent vectors on the surface. A real experiment was conducted to measure simple plane surfaces, circular surfaces, and complex sculptures. The results show that the process of calculating surface normals is fast and reliable, and we have computed 1654 surface normals in 29.4 milliseconds for complex surfaces such as sculptures.

In this paper, an algorithm is proposed to solve the non-convex optimization problem using sequential convex programming. An approximation method was used to solve the collision avoidance constraint. An iterative approach was utilized to estimate the non-convex constraints, replacing them with their linear approximations. Through the simulation, we can see that this method allows for quadcopters to take off from a given initial position and fly to the desired final position within a specified flight time. It is guaranteed that the quadcopters will not collide with each other in different scenarios.

This paper presents a novel Continuous Variable Transmission (CVT) design. CVT is highly beneficial for actuators with rotary output as it can improve the energy efficiency of the actuators by providing an optimum transmission ratio. This property of CVT is highly beneficial for fossil-fuel-based vehicles, electric vehicles, wind turbines, industrial robots, etc. With the exception of Spherical CVT and DH CVT, all known CVTs like push belt CVTs, toroidal CVTs, Milner CVTs, etc., require additional gear sets and clutches for direction reversal and neutral gear ratio. However, Spherical CVT and DH CVT have low torque capacity due to a single traction point constraint. Foregoing in view, a new CVT named CAD CVT has been developed. The paper presents the design conception, the operating principle, the transmission ratio, the torque capacity, frictional losses, and experimental verification of the basic functionality by manufacturing a Proof of Concept (PoC). The proposed CVT is the only CVT capable of independent direction reversal and high torque capacity as it can transmit torque through multiple traction points. The new CVT will significantly impact high-torque applications in different engineering applications, especially land transport consisting of heavy vehicles like trucks, buses, and trailers.

In this paper, a novel control architecture is proposed in which FMPC couples feedback from model predictive control with feedforward linearization. The proposed approach has the computational advantage of only requiring a convex quadratic program to be solved instead of a nonlinear program. Feedforward linearization aims to overcome the robustness issues of feedback linearization, which may be the result of parametric model uncertainty leading to inexact pole-zero cancellation. A DenseNet was trained to learn the inverse dynamics of the system, and it was used to adjust the desired path input for FMPC. Through experiments using quadcopter, we also demonstrated improved trajectory tracking performance compared to that of the PD, FMPC, and FMPC+DNN approaches. The root mean square (RMS) error was used to evaluate the performance of the above four methods. The results demonstrate that the proposed method is effective.

In this research, we combined two distinct, structured light methods, the single-shot pseudo-random sequence-based approach and the time-multiplexing stripe indexing method. As a result, the measurement resolution of the single-shot, spatially encoded, pseudo-random sequence-based method improved significantly. Since the time-multiplexed stripe-indexed-based techniques have a higher measurement resolution, we used varying stripes to enhance the measurement resolution of the pseudo-random sequence-based approaches. We suggested a multi-resolution 3D measurement system that consisted of horizontal and vertical stripes with pixel sizes ranging from 8 × 8 to 16 × 16. We used robust pseudo-random sequences (M-arrays) to controllably distribute various stripes in a pattern. Since single-shape primitive characters only contribute one feature point to the projection pattern, we used multiple stripes instead of single-shape primitive symbols. However, numerous stripes will contribute multiple feature points. The single character-based design transforms into an increased featured size pattern when several stripes are employed. Hence, the projection pattern contains a much higher number of feature points. So, we obtained a high-resolution measurement. Each stripe in the captured image is located using adaptive grid adjustment and stripe indexing techniques. The triangulation principle is used to measure 3D.

In this study, the dynamics of tether cables (TCs) that connect a surface ship and a walking robotic vehicle on the seabed are numerically investigated. The main aim of this study is to develop a reliable prediction model for the dynamic behavior of TCs attached to a seabed walking robot. This system consists of a surface ship, underwater manned seabed walking robot (UMSWR), TC, and winch. The study is comprised of mathematical modeling and numerical simulations of the developed governing equations for the TC dynamics. A relatively simple and efficient mathematical analysis method is proposed to determine the configuration and forces on the TC under a steady state. The problem is solved using the quasi-static technique and lumped mass parameters for discretizing and modeling the dynamics of the TC. Based on the static analysis of the Morrison equation and finite segment method, analytical formulas of the steady-state equation of TC were obtained and solved. The effects of variable water density and variable underwater currents are included in the cable behavior. Consequently, the two-dimensional TC profile and axial tension were estimated in a steady-state configuration. The developed equations were simulated in MATLAB software. Several numerical simulation examples were worked out, demonstrating the accurate performance of the method. Various input parameters of the system and their relationships with the output values were investigated, thereby demonstrating the versatility of the method.

This paper presents the design optimization of composite submersible cylindrical pressure hull subjected to 3 MPa hydrostatic pressure. The design optimization study is conducted for cross-ply layups [0s/90t/0u], [0s/90t/0u]s, [0s/90t]s and [90s/0t]s considering three uni-directional composites, i.e. Carbon/Epoxy, Glass/Epoxy, and Boron/Epoxy. The optimization study is performed by coupling a Multi-Objective Genetic Algorithm (MOGA) and Analytical Analysis. Minimizing the buoyancy factor and maximizing the buckling load factor are considered as the objectives of the optimization study. The objectives of the optimization are achieved under constraints on the Tsai-Wu, Tsai-Hill and Maximum Stress composite failure criteria and on buckling load factor. To verify the optimization approach, optimization of one particular layup configuration is also conducted in ANSYS with the same objectives and constraints.

The Structure Light System (SLS) is a general concept and it is one of the cheapest methods for the non-contact-based 3D reconstruction. The existing single-shot SLS which is primarily based on the spatial encoding techniques are not optimal in terms of resolution and digitally encoded patterns. Those schemes are not flexible, controllable, and designed up to the level of the pixel. So, to increase the resolution and to implement a flexible controllable pattern we proposed a novel heuristic method based on the spatial neighborhood. In this paper, we propose a multi-resolution SLS which can be implemented with a set of 25 geometrical shaped distinct symbols or alphabets to use in the projection pattern as shape primitive. The size of each symbol is well defined in pixels which enabled us to have access and control up to the full resolution of the projector. The shape descriptive parameters for each symbol or alphabet are also defined and computed. To spread the alphabets in a controllable manner, a method is defined to generate a robust pseudo-random sequence of any required size with a certain number of alphanumeric bases, to be employed in the projection pattern concerning the measured resolution. This arrangement will enable us to design the projection patterns according to the required surface area and the resolution. A new technique is developed for the decoding of the captured image pattern. The decoding process depends upon the classification of symbols which is based on shape descriptive parameters. The searching in the neighborhood of a symbol is carried out through computing the location information, grid distance, and direction information to find the codewords which are used to establish the correspondence.

Wireless charging has become an emerging challenge to reduce the cost of a conventional plug-in charging system in electric vehicles especially for supercapacitors that are utilized for quick charging and low-energy demands. In this article, the design of an efficient wireless power transfer system has been presented using resonant inductive coupling technique for supercapacitor-based electric vehicle. Mathematical analysis, simulation, and experimental implementation of the proposed charging system have been carried out. Simulations of various parts of the systems are carried out in two different software, ANSYS MAXWELL and MATLAB. ANSYS MAXWELL has been used to calculate the various parameters for the transmitter and receiver coils such as self-inductance ( L ), mutual inductance ( M ), coupling coefficient ( K ), and magnetic flux magnitude ( B ). MATLAB has been utilized to calculate output power and efficiency of the proposed system using the mathematical relationships of these parameters. The experimental setup is made with supercapacitor banks, electric vehicle, wattmeters, controller, and frequency generator to verify the simulation results. The results show that the proposed technique has better power transfer efficiency of more than 75% and higher power transfer density using a smaller coil size with a bigger gap of 4–24 cm.

Objectives: Berberis lycium, Adhatoda vasica, and Zizypus jujuba are common worldwide medicinal plants. These plants are used in different diseases by local people. However, the scientific rationale for the use of these plants is limited especially in diseases arising from oxidative stress. This study was therefore aimed to evaluate the antioxidant, antidiabetic, and anti-gout activity of these plants from Kashmir flora. Methods: The antioxidant activities were studied by different in vitro assays which include lipid peroxidation assay, DPPH assay, ABTS assay, iron chelation assay, total phenolic and flavonoid contents. The antidiabetic activity of plants extracts was analyzed by the inhibition of alpha glucosidase, while anti-gout activities were observed by the inhibition of xanthine oxidase enzyme. Results: All plants extract exhibited good antioxidant activities which are due to significant metal chelating ability and inhibition of lipid peroxidation. The maximum inhibitory effect against lipid peroxidation was observed in water extract of Berberis lycium root extracts. The maximum antidiabetic activity was shown by acetone extract of Berberis lyceum roots justifying its popular use in diabetes. Acetone extract of Zizypus jujuba showed excellent inhibition of xanthine oxidase justifying its popular use in gout. The high antioxidant and enzyme inhibitory activities of these plants might be due to high phenolic and flavonoid contents. Conclusion: Based on these results, it is concluded that Zizpus jujuba, Adhatoda vasica and Berberis lycium are rich source of antioxidants and may be utilized as antidiabetic and antigout agents.