Process involved in designing of an intelligent additional track mechanism tracked vehicle for swamp peat terrain

Different types of off road vehicles are widely used in agriculture, oil industry, mining and military operations but none of them can effectively operate over the swamp peat terrain because of its low bearing capacity of 7kN/m 2. Segmented rubber tracked vehicle and intelligent air-cushion system tracked vehicle were developed in Malaysia for swamp peat terrain.16kN/m2 of ground pressure was exerted by using the segmented rubber tracked vehicle during field operation therefore could not be operated efficiently. The air-cushion tracked vehicle increased the floatation capacity but at the same time increased the frictional effects therefore the tracks of the vehicle easily slipped out from the traction wheels during operation. Addressing these issues an intelligent additional track mechanism for tracked vehicle has been designed to improve the mobility over swamp peat terrain where the additional track would be increased the ground surface area and reduced the vehicle ground pressure. This paper presents the process involved in designing the intelligent additional track mechanism tracked vehicle for transportation of agricultural and industrial goods on the swamp peat terrain with bearing capacity of 7kN/m2. The mechanical design comprises of track vehicle frame with track mechanism. Additional track mechanism with Fuzzy expert system. The design parameters are optimized using developed mathematical model based on the dynamics and kinematics behavior of the vehicle. In order to increase the vehicle contact surface area and reduce the surface contact pressure the additional track mechanism is designed in such way that it can be folded and unfolded from its position by using the ball-screw scissor lift mechanism. While, Fuzzy expert system is used to control the movement of the lift mechanism based on 70mm critical sinkage of vehicle detected from a set of sensors. The completed to vehicle system would be used for off-road applications as required

Inkjet printing of resistively loaded FSS for microwave absorbers

Inkjet printing is proposed as a means to create the resistively loaded elements of a frequency selective surface(FSS) which suppresses radar backscatter when placed above a metal ground plane. Spectral transmission and reflection measurements from 9 to 18 GHz show that the dot density of the printed features and the volume ratio of an aqueous vehicle and nano-silver (Ag) ink mixture can be selected to obtain surface resistances in the range 1.2 – 200 Ω/sq

Simpler, low-cost stealth

FSS-based RAM that is thin, low-cost, robust and simple to manufacture can provide broadband absorption from a wide range of angles

Ultra Thin Resistively Loaded FSS Absorber For Polarisation Independent Operation at Large Incident Angles

In this paper we report on a resistively loaded Frequency Selective Surface (FSS) absorber design which is insensitive to the polarization of microwave signals incident at angles of 45º ± 5º. The metal backed periodic structure is composed of an array of conductive rectangular loops, each loaded with a resistor at the center of the four sides. The geometry of the absorber and the resistance value of the vertical and horizontal resistor pairs are carefully chosen so that the structure presents a real impedance of 377 Ohms at the center operating frequency for both TE and TM polarized waves incident at 45º. Numerical predictions of the electromagnetic scattering from three different absorbers, designed to work at X band, are used to investigate the effect of thickness and resistance value on the reflectivity bandwidth and angular sensitivity

Polarisation independent split ring frequency selective surface

A frequency selective surface (FSS) is described which exhibits coincident spectral responses for TE and TM polarisation when the FSS operates at 45° incidence. The structure consists of two closely spaced arrays of ring elements with the conductor split at one or two locations to provide independent control of the resonances for the vertical and horizontal field directions. The FSS is designed to diplex two channels separated by an edge of a band ratio of 1.7:1 and yield a common - 10 dB reflection bandwidth of 10.2%. Measured and numerical results are shown to be in good agreement over the frequency range 9-12 GHz