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A novel method for Single Event Effect (SEE) Radiation Testing using Built-In Self-Test (BIST) feature of indigenously developed Vikram1601 processor is discussed. The novelty is that the usage of BIST avoids need of exhaustive test vectors to ensure test coverage of all the internal registers and physical memory to store them. So processor is the only element vulnerable to radiation damage during testing. The test design was carried out at VSSC, Trivandrum and the testing was carried out at IUAC, Delhi. In the first part, a brief introduction, need and methods of radiation testing of electronics especially SEE of radiation on Silicon based devices, different radiation effects, radiation damage mechanisms and testing methods are described. A brief introduction to Vikram1601 processor, the instruction – TST, used as BIST and testing scheme implementation using TST for studying the SEE is explained.

Abstract : In any human space flight program, safety of the crew is of utmost priority. In case of exigency during atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew escape system. Crew escape system is a crucial part of the Human Space flight vehicle which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the crew escape system during the mission abort are severe as the propulsive forces, aerodynamic forces and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight time considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters.

From SAE International, SAE MobilityRxiv is a free online preprint server and sharing service for English-language preprints in the mobility/transportation field

digital standards systems an integrated approach to engineering standards usage

Now Available from SAE International, SAE OnQue is a revolutionary digital standards solution that optimizes the way automotive and aerospace engineers access standards.

Autonomous driving technology is more and more important nowadays, it has been changing the living style of our society. As for autonomous driving planning and control, vehicle dynamics has strong nonlinearity and uncertainty, so vehicle dynamics and control is one of the most challenging parts. At present, many kinds of specific vehicle dynamics models have been proposed, this review attempts to give an overview of the state of the art of vehicle dynamics models for autonomous driving. Firstly, this review starts from the simple geometric model, vehicle kinematics model, dynamic bicycle model, double-track vehicle model and multi degree of freedom (DOF) dynamics model, and discusses the specific use of these classical models for autonomous driving state estimation, trajectory prediction, motion planning, motion control and so on.

The test method describes the procedure for determination of the total acid number (TAN) of new and degraded polyol ester and diester-based gas turbine lubricants by the potentiometric titration technique. The method was validated to cover an acidity range of 0.05 to 6.0 mg KOH g-1. The method may also be suitable for the determination of acidities outside of this range and for other classes of lubricants.

In numerous industries such as aerospace and energy, components must perform under significant extreme environments. This imposes stringent requirements on the accuracy with which these components are manufactured and assembled. One such example is the positional tolerance of drilled holes for close clearance applications, as seen in the “EN3201:2008 Aerospace Series – Holes for metric fasteners” standard. In such applications, the drilled holes must be accurate to within ±0.1 mm. Traditionally, this required the use of Computerised Numerical Control (CNC) systems to achieve such tight tolerances. However, with the increasing popularity of robotic arms in machining applications, as well as their relatively lower cost compared to CNC systems, it becomes necessary to assess the ability of robotic arms to achieve such tolerances. This review paper discusses the sources of errors in robotic arm drilling and reviews the current techniques for improving its accuracy.

This document focuses on the latest in-force regulations. However, in addition to latest information, the report may include historical information. As regulations are superseded, the previous entry will remain to help understand the change in requirements over time. The initial focus of the document includes light-, medium-, and heavy-duty on-road vehicles with all propulsion systems. The document will include information from the United States and Canada, with later publications expanding to other regions. Forecasts for future regulations will not be included in the spreadsheet but be kept in a separate document. The document may be expanded to other types of applications/vehicles as information becomes available.

In radiography testing, the radioactive elements Iridium 192 (Ir192) and Cobalt 60 (Co60) are employed to detect subsurface and inner flaws. These radioactive components are kept secure within the radiation-protected source camera. Despite the fact that the camera is safe, there is a little quantity of radiation that may harm human body cells. In this present study, it restricts radiation emission by placing a lead sheet over the source camera, which absorbs the produced radiation. The innovative concept involves in this present work is to place a manually operated switch near the radiation source to emit radiation.

This SAE Aerospace Recommended Practice (ARP) is an industrial collaboration with regulatory bodies like the European Aviation Safety Agency (EASA) and the Federal Aviation Administration (FAA) to determine the worst-case credible thermal runaway (TR) condition (energy released and maximum temperature) for the design of an aviation large propulsion battery system to quantitatively verify TR in lieu of battery level RTCA DO-311A testing with protections disabled. The ARP considers the three stages of TR within a cell and defines the two critical temperatures for a specific cell design. These temperatures are key to understanding the layers of monitoring necessary to determine the severity of a TR event. Different trigger methods can be used to quantify the heating characteristics and resultant energy profile releases as a function of time.

This specification establishes requirements for a corrosion-removing compound in the form of a liquid concentrate.

This specification covers requirements for silver deposited on metal parts with a nickel strike between the basis metal and the silver deposit.

This document provides guidance for a means of showing compliance with regulations for protection against lightning direct effects for aircraft of conventional design, as well as for those involving advanced composite structures or other new technologies. This guidance also applies to those aspects of aircraft systems and components not addressed in the regulations covering the protection of electrical/electronic systems (for example, FAR/JAR xx.1316) or fuel systems (for example, xx.954). The guidance provided in this document applies to initial designs as well as modifications.

This document covers metric studs made from a corrosion and heat resistant, age hardenable iron base alloy of the type identified under the Unified Numbering System as UNS S66286. The following specification designations and their properties are covered: