Cumulative Index to NASA Tech Briefs, 1963 - 1966

Cumulative index of NASA Tech Briefs dealing with electrical and electronic, physical science and energy sources, materials and chemistry, life science, and mechanical innovation

Cumulative index to NASA Tech Briefs, 1963-1967

Cumulative index to NASA survey on technology utilization of aerospace research outpu

NASA Tech Briefs Index, 1977, volume 2, numbers 1-4

Announcements of new technology derived from the research and development activities of NASA are presented. Abstracts, and indexes for subject, personal author, originating center, and Tech Brief number are presented for 1977

Proceeding Of Mechanical Engineering Research Day 2015 (MERD’15)

This Open Access e-Proceeding contains 74 selected papers from the Mechanical Engineering Research Day 2015 (MERD’15) event, which is held in Kampus Teknologi, Universiti Teknikal Malaysia Melaka (UTeM) - Melaka, Malaysia, on 31 March 2015. The theme chosen for this event is ‘Pioneering Future Discovery’. The response for MERD’15 is overwhelming as the technical committees have received more than 90 papers from various areas of mechanical engineering. From the total number of submissions, the technical committees have selected 74 papers to be included in this proceeding. The selected papers are grouped into 12 categories: Advanced Materials Processing; Automotive Engineering; Computational Modeling and Analysis & CAD/CAE; Energy Management & Fuels and Lubricants; Hydraulics and Pneumatics & Mechanical Control; Mechanical Design and Optimization; Noise, Vibration and Harshness; Non-Destructive Testing & Structural Mechanics; Surface Engineering and Coatings; Others Related Topic. With the large number of submissions from the researchers in other faculties, the event has achieved its main objective which is to bring together educators, researchers and practitioners to share their findings and perhaps sustaining the research culture in the university. The topics of MERD’15 are based on a combination of advanced research methodologies, application technologies and review approaches. As the editor-in-chief, we would like to express our gratitude to the editorial board members for their tireless effort in compiling and reviewing the selected papers for this proceeding. We would also like to extend our great appreciation to the members of the Publication Committee and Secretariat for their excellent cooperation in preparing the proceedings of MERD’15

Effect of process parameters on the mechanical properties and failure behavior of spot welded low carbon steel

In this research, the effect of spot welding parameters on weld quality was investigated. The main affecting welding parameters such as weld current, weld time, electrode force and holding time were determined as the basis for quality evaluation. The selected quality features were classified into mechanical properties and failure behavior, which were required for application with highly dynamic loading. The peak load as one of the important mechanical properties, as well as the two distinct failure modes which were cross-nugget and complete button pull, were observed using tensile-shear stress. To obtain detailed shear stress testing results and to determine the significance of parameters, a servo-hydraulic testing machine was run at a constant cross-head speed of 2mm/min followed by statistical analysis methods, which were Taguchi’s L16 orthogonal array and Analysis of Variance (ANOVA). Furthermore, the failure mode was to be observed based on the fracture surface used as reference for acceptance or rejection of the weld joint. Based on the results, the weld current was the significant factor affecting shear stress and the complete button pull was mostly found, which leads to the satisfactory condition of the joint. Cross-nugget and full button pull-out were the dominant failures observed in the lap-shear test. The cross-nugget failure leads to a low shear load, while complete button pull-out displays maximum shear load

Some NASA contributions to human factors engineering: A survey

This survey presents the NASA contributions to the state of the art of human factors engineering, and indicates that these contributions have a variety of applications to nonaerospace activities. Emphasis is placed on contributions relative to man's sensory, motor, decisionmaking, and cognitive behavior and on applications that advance human factors technology

Real-time Expulsion Detection and Characterization in Ultrasound M-scans of the Resistance Spot Welding Process

In this work, ultrasound is used as a non-destructive method of monitoring the welding process in real-time to detect expulsion events. During spot welding, a single element ultrasound transducer placed behind one of the welding electrodes operates in pulse-echo mode and probes the axial center of the welded zone. Acoustic reflections from the electrodes, plate interfaces and liquid metal weld nugget are recorded as A-scans. During welding, the A-Scan reflections change with time, since the material properties of steel (e.g. density and elasticity) change with temperature. Imaging successive A-scans in time forms an M-Scan image of the welding process from which the dynamic formation of the spot weld can be depicted and analyzed. This thesis focuses on taking a brand new approach to the problem of expulsion detection by identifying and characterizing expulsion events in M-scan data. Expulsion occurs when molten material is ejected from the welded zone as a result of overheating due to: poor electrical/thermal contact, coating thickness and/or excessive weld current. An expulsion can have a significant impact on the final yield strength of the weld, and thus the detection and characterization of expulsion events is significant to the quality assurance of resulting spot welds. The main contribution of this work was the discovery of M-scan features that provide a means of detecting, predicting and classifying the event. These include: 1) Detection by sudden phase delay change of the workpiece surface reflection. 2) Prediction by ultrasonically measuring the heating rate prior to expulsion. 3) Classification of the weld quality by ultrasonically measuring indentation in the heated workpiece. In addition, new methods for automatically detecting and measuring these features were developed that utilize a new efficient Hough transform variant proposed in this work. It was shown using both lab experiments and industrial data that not only does the automatic detection of these features provide a new and robust means of identifying expulsions in a wide range of welding setups, but this research can also be used in the future to provide real-time feedback to dynamic weld controllers and eliminate expulsions from occurring altogether

Cumulative index to NASA Tech Briefs, 1963-1965

Annotated bibliography of NASA technical briefs on electrical, energy sources, materials, life sciences, and mechanical informatio

Intelligent laser cladding control system design and construction.

Imperial Users onl

Robotic hand controlled based on flexible sensor by glove using wireless communication

A humanoid robot's hand is a vital component. It's tough to create an action that looks like a human side. This study suggested a similar-sized and light-weight robotic hand and investigated the possibility of controlling based on flexible sensor by glove using wireless communication. The robotic hand is built to manoeuvre and function like a human hand. One of the robot hand's fingers has three degrees of freedom, nearly identical to a human finger. When the fingers of the manipulator switch, the glove using wireless communication sends a feedback signal to the microcontroller. Each robot hand's finger sector is powered by a Servo Motor chain drive. Furthermore, since the servo motor can only supply a low torque for the finger, the robot hand can only produce a force that is appropriate for each finger. Arduino Mega monitor the robot's entire behaviour and activity. The robot hand is managed in real time by the glove using wireless communication. As a result, it may perform tasks similar to those performed by a human hand, such as gripping an object. The robot hand will be used to implement humanoid robots with further research and developmen