Molten Salt Synthesized Submicron Perovskite La1–xSrxCoO3 Particles as Efficient Electrocatalyst for Water Electrolysis

Perovskite oxides are an important and effective class of mixed oxides which play a significant role in the fields of energy storage and conversion systems. Here we present a series of cobaltite perovskite LaCoO3 particles which have been doped with 0, 5, 10, 20, and 30% of Sr2C and have been synthesized by a combined sol– gel and molten-salt synthesis procedure, which provides a regular morphology of the particles. These Sr2C-doped LaCoO3 particles have been characterized by powder X-ray diffraction, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Moreover, these Sr2C doped LaCoO3 particles have been demonstrated as efficient catalysts for oxygen evolution reaction (OER) based on the measured specific capacitance, total charge, most accessible charge, electrochemically active surface area, and roughness factor using rotating disk and rotating ring-disk electrode techniques. The 30% Sr2C-doped LaCoO3 sample shows enhanced electrocatalytic OER activity in 0.5 M H2SO4 media compared to the LaCoO3 samples doped with 0, 5, 10, and 20% Sr2C. Among all five LaCoO3 samples, the doped LaCoO3 samples demonstrate better OER activity than the undoped sample

SPHERES Reconfigurable Framework and Control System Design for Autonomous Assembly

Reconfigurable control system design is a key component for enabling autonomous on-orbit assembly. Current research on reconfigurable control systems focuses on adapting to failures. However, for assembly scenarios, the reconfiguration is necessitated by changing mass and stiffness properties. This paper provides a brief description of existing reconfigurable control system technology and develops a framework to incorporate reconfiguration into an existing baseline system to account for mass property variations. The reconfigurable control system framework has been developed and implemented using the SPHERES (Synchronized Position Hold Engage Reorient Experimental Satellites) testbed as the baseline system. The framework highlights the elements that need to be updated, introduces a variable p that captures the configuration, and details the updates necessary in the key algorithms to calculate the model online using p. Results are presented from the implementation on the SPHERES, focusing on the reconfigurable estimator. Plans are presented for an integrated assembly test that demonstrates the maintenance of stability, fuel efficiency, and accuracy throughout configuration changes that occur during assembly

An advanced deep learning model for maneuver prediction in real-time systems using alarming-based hunting optimization

The increasing trend of autonomous driving vehicles in smart cities emphasizes the need for safe travel. However, the presence of obstacles, potholes, and complex road environments, such as poor illumination and occlusion, can cause blurred road images that may impact the accuracy of maneuver prediction in visual perception systems. To address these challenges, a novel ensemble model named ABHO-based deep CNN-BiLSTM has been proposed for traffic sign detection. This model combines a hybrid convolutional neural network (CNN) and bidirectional long short-term memory (BiLSTM) with the alarming-based hunting optimization (ABHO) algorithm to improve maneuver prediction accuracy. Additionally, a modified hough-enabled lane generative adversarial network (ABHO based HoughGAN) has been proposed, which is designed to be robust to blurred images. The ABHO algorithm, inspired by the defending and social characteristics of starling birds and Canis kojot, allows the model to efficiently search for the optimal solution from the available solutions in the search space. The proposed ensemble model has shown significantly improved accuracy, sensitivity, and specificity in maneuver prediction compared to previously utilized methods, with minimal error during lane detection. Overall, the proposed ensemble model addresses the challenges faced by autonomous driving vehicles in complex and obstructed road environments, offering a promising solution for enhancing safety and reliability in smart cities

Behavioural Fault tolerant control of an Omni directional Mobile Robot with Four mecanum Wheels

This paper analyses the four-mecanum wheeled drive mobile robot wheels configurations that will give near desired performance with one fault and two faults for both set-point control and trajectory-tracking (circular profile) using kinematic motion control scheme within the tolerance limit. For one fault the system remains in its full actuation capabilities and gives the desired performance with the same control scheme. In case of two-fault wheels all combinations of faulty wheels have been considered using the same control scheme. Some configurations give desired performance within the tolerance limit defined while some does not even use pseudo inverse since using the system becomes under-actuated and their wheel alignment and configurations greatly influenced the performance

Reconfiguration methods for on-orbit servicing, assembly, and operations with application to space telescopes

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2007.Includes bibliographical references (p. 115-118).Reconfiguration is an important characteristic in furthering on-orbit servicing, assembly, and operations. Previous work has focused on large assemblers manipulating small payloads, where the dynamics of the assembler is not significantly changed. This work seeks to identify the impact of reconfiguration on maneuver performance. Reconfiguration is considered in two categories: implementation and application. Implementation of reconfiguration consisted of developing a method for defining and updating a configuration, implementation on the SPHERES testbed, and execution of tests (in simulation and on the International Space Station) to assess the control performance improvement after reconfiguration. Four applications were considered in this work, two hardware applications and two systems applications modeled through simulation. The objective of the SWARM application was to demonstrate autonomous assembly capability through docking and undocking maneuvers. The objective of the SIFFT application was to demonstrate formation reconfiguration capability, through the expansion and rotation of an equilateral triangle of three satellites. The objective of the systems applications was to determine the impact of re-configuration in a larger mission context.(cont.) One application, Mass Property Update, considered how the choice of method for obtaining the mass property information impacts operations. The other application, Modularity Analysis, considered how the implementation of modularity is driven by the mission objectives. Overall, this work has served to demonstrate the control impact of reconfiguration though implementation on the SPHERES testbed. This implementation was used on two hardware applications to determine the performance of reconfiguration for assembly and formation reconfiguration missions. Also, the impact of reconfiguration has been studied in the broader systems context. The choice of method of mass property update was demonstrated to have an impact on operations, in terms of reliability and mass. Finally, the method incorporation of modularity for purposes of on-orbit servicing and assembly was demonstrated to be driven by mission design parameters.by Swati Mohan.S.M

COMPARISON OF EFFICIENCY OF APM AND MNO2 BY PHOTOCATALYTICAL DEGRADATION OF AZURE-B BASED ON QUALITY PARAMETER MODIFICATION

This paper describes the comparison of photocatalytical activity of Ammonium Phosphomolybdate(APM) and Manganese(IV) Oxide  forphotocatalytic degradation of Azure-B. This study is based on modificationsin quality parameters which take place during optimum photocatalytic degradation of Azure-B contaminated water using two hetrocatalystAmmonium Phosphomolybdate and Manganese(IV) Oxide separately. Various quality parameterslike pH, Alkalinity, Hardness, COD, BOD, DO, Conductivity, Salinity, TDS, and Concentration of  Ca+2, Mg+2, Cl-, F-, NO3-, SO4-2 and turbidity were used for comparison

Performance Investigations of an Improved Backstepping Operational space Position Tracking Control of a Mobile Manipulator

This article implies an improved backstepping control technique for the operational-space position tracking of a kinematically redundant mobile manipulator. The mobile manipulator thought-out for the analysis has a vehicle base with four mecanum wheels and a serial manipulator arm with three rotary actuated joints. The recommended motion controller provides a safeguard against the system dynamic variations owing to the parameter uncertainties, unmodelled system dynamics and unknown exterior disturbances. The Lyapunov’s direct method assists in designing and authenticating the system’s closed-loop stability and tracking ability of the suggested control strategy. The feasibility, effectiveness and robustness of the recommended controller are demonstrated and investigated numerically with the help of computer based simulations. The mathematical model used for the computer-based simulations is derived based on a real-time mobile manipulator and the derived model is further verified with an inbuilt gazebo model in a robot operating system (ROS) environment. In addition, the proposed scheme is verified on an in-house fabricated mobile manipulator system. Further, the recommended controller performance is correlated with the conventional backstepping control design in both computer-based simulations and in real-time experiments

Simplified Motion Control of a Vehicle manipulator for the Coordinated Mobile Manipulation

This paper considers a resolved kinematic motion control approach for controlling a spatial serial manipulator arm that is mounted on a vehicle base. The end-effector’s motion of the manipulator is controlled by a novel kinematic control scheme, and the performance is compared with the well-known operational-space control scheme. The proposed control scheme aims to track the given operational-space (end-effector) motion trajectory with the help of resolved configuration-space motion without using the Jacobian matrix inverse or pseudo inverse. The experimental testing results show that the suggested control scheme is as close to the conventional operational-space kinematic control scheme

Urea Biosensor Based on Conducting Polymer Transducers

Non

On-Orbit Assembly of Flexible Space Structures with SWARM

On-orbit assembly is an enabling technology for many space applications. However, current methods of human assisted assembly are high in cost and risk to the crew, motivating a desire to automate the on-orbit assembly process using robotic technology. Construction of large space structures will likely involve the manipulation of flexible elements such as trusses or solar panels, and automation for assembly of flexible structures has significant challenges, particularly in control systems. This paper presents results of ground-based experiments on the assembly of a flexible space structures using the hardware developed under the Self-Assembling Wireless Autonomous Reconfigurable Modules (SWARM) program. Results are shown for a series of incremental tests that demonstrate control of a flexible structure, docking, and reconfiguration after docking. These results demonstrate the feasibility of the assembly of flexible structures using this methodology.United States. National Aeronautics and Space Administration. Small Business Innovation Program (Contract NNM07AA22C