史密斯威爾森

Abstract In the fields of competition shooting and handgun engineering, it is highly desirable to be able to properly assess and measure handgun recoil. If recoil could be measured, it would be useful to the competition shooter in his continuous quest to evaluate modifications for his equipment and methods. The engineer would benefit since the results of measured testing would quantify the reaction forces present allowing proper stress analysis and the ability to calibrate FEA models. The objective of this project was to design and develop a device capable of measuring recoil forces on multiple independent axes. The device will respond and measure only on the axis the load is applied to. It was determined that the most cost effective way to meet the design specifications was to utilize strain gage based transducer technology. A custom multiple axes Dynamometer was designed, fabricated and interfaced with the Smith & Wesson CATS (Computer Aided Testing System) data collection system. The system was calibrated and tested with a model 4013TSW pistol and the results were graphed. The results showed peak values of 950 lb. for the horizontal recoil force, 125 ft-lb. for the recoil moment, and 24 ft-lb. for the rifling torque. Taking factors into consideration, these values are close to the expected values. The Dynamometer exhibited ringing at about 310 Hz. due to its natural frequency and required filtering to properly observe the load profile. When low-pass filtered at 100 Hz., the load profile stood out, but the amplitude was attenuated. The net result was that peak values were observed in the standard data, while the load profile and gun signature could be identified in the filtered data. The device was found to be useful for qualitative analysis, but was deemed inadequate for impact and high frequency applications. The Dynamometer could be improved with efforts made to raise the natural frequency and advanced filtering techniques.

Abstract In any handgun, the force of the trigger pull and the distance traveled by the hammer during the trigger pull, produce the energy required to ignite the primer on the cartridge. Reducing either of these characteristics can lead to insufficient firing pin energy, while increasing either of these can result in a punctured primer that will result in malfunctioning of the firearm. The reliability and dependability of a handgun are extremely important to a Law Enforcement Officer since his life may be on the line. To this end, the development of a computer driven device that is capable of measuring these characteristics is necessary for firearms manufacturers to control both the feel and lock work function of the firearm detection. Test results are archived for performing statistical process control and report preparation. A PC-based monitoring system for evaluating the performance characteristics of the trigger-pull of pistols has been designed and developed. This system uses an in-house developed load cell along with external clock pulses derived from a shaft encoder to collect approximately 27000 equally spaced load data points. The acquired data points which are 0.0002 inches apart are plotted for visual inspection and analyzed on real time to detect any possible fault associated with the trigger pull mechanism. Digital signal processing is extensively used for filtering, integration and triggerroughness. Visual Basic for Windows® Programming environment has been employed to create the user interface and perform data acquisition, servomotor control, Statistical Process Control, data base management and report preparation.

Abstract In the past decade, sophisticated mathematical, statistical and graphical routines have been added to spreadsheet packages, thus converting them to serious analytical tools. The engineering community has adopted these packages to perform various sensitivity analyses on design problems which lend themselves to these types of applications. Design engineers can now rapidly and conveniently utilize these tools to perform a wide variety of analyses on design problems having simple geometries and loading conditions, without having to develop any FORTRAN, Basic or C code. This paper is concerned with the applications of spreadsheet packages in the area of steady and transient thermal analysis, design optimization and solution of initial-value differential equations. Lotus 1-2-3 in conjunction with the explicit finite difference method (Gauss-Seidel method) has been used to predict transient temperature distribution in an axi-symmetric model of the barrel of a handgun. Borland International Quattro Pro spreadsheet program along with Runge-Kutta and Newmark numerical integration techniques have been employed to optimally design the recoil system of a handgun. Also, the use of Quattro Pro for constructing the contour plots of temperature in a Very Large Scale Integrated (VLSI) chip and the IBM 3081 TCM cold plate are demonstrated. Finally, the built-in Error and Bessel functions in Microsoft Excel have been used to find temperature distribution in a semi-infinite and cylindrical objects.

This paper describes the development of an expert system designed to advise on management strategies for beef cattle farmers who wish to improve their production systems. This task requires an integration of knowledge from a number of overlapping domains including cattle breeding, pasture improvement and pasture quality. We describe our approach to the problem of providing advice from more than one domain of expertise. We propose that by developing separate modules for each domain, using consistent terminology in all modules, and identifying where communication with another module is required, it is possible to develop an integrated multiple domain expert system.