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Accurate information of inertial parameters is critical to motion planning and control of space robots. Before the launch, only a rudimentary estimate of the inertial parameters is available from experiments and computer-aided design (CAD) models. After the launch, onorbit operations substantially alter the value of inertial parameters. In this work, we propose a new momentum model-based method for identifying the minimal parameters of a space robot while on orbit. Minimal parameters are combinations of the inertial parameters of the links and uniquely define the momentum and dynamic models. Consequently, they are sufficient for motion planning and control of both the satellite and robotic arms mounted on it. The key to the proposed framework is the unique formulation of momentum model in the linear form of minimal parameters. Further, to estimate the minimal parameters, we propose a novel joint trajectory planning and optimization technique based on direction combinations of joints' velocity. The efficacy of the identification framework is demonstrated on a 12 degreesof-freedom, spatial, dual-arm space robot. The methodology is developed for tree-type space robots, requires just the pose and twist data, and scalable with increasing number of joints.

This paper presents a practical approach of model updating based on high-dimensional model representation (HDMR). The proposed methodology involves integrated finite element modeling, obtaining explicit relationships between the structural responses and parameters using HDMR and minimization of objective function developed using structural responses obtained from HDMR approximation functions using genetic algorithm. First, the efficiency of the proposed method is demonstrated by considering a simply supported beam example. Later model updating of an existing bridge is considered to check the adequacy of the proposed method.

The behaviour of any structuredepends upon the structural element present in it. The critical aspect on which the structural configuration depends are shape, length and geometry of the building. In the present study the performance of vertical geometric irregular tall structures under the wind load is evaluated as per IS 16700: 2017 provisions. Three type of vertical geometric irregular tall reinforced concrete buildings having different plan dimensions with cantilevered offset length varying from 11% to 15% of the building lateral dimension with increment of 0.5% are modelled. Modal analysis and wind analysis are performed using structural analysis software ETABS to assess the behaviour of vertical geometric irregular tall structural system with cantilevered offset. Parameter such as time period, frequency, storey displacement and storey drift are studied and compared with the regular building. Multiple linear regression analysis is carried out to formulate a general expression for the responses of the vertical irregular tall buildings.

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