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T h i s w o r k i s concerned with the modeling and c o n t r o l o f a r o b o t t h a t i s m o u n t e d on a m o v i n g p l a t f o r m . The p l a t f o r m i s s u b j e c t e d t o random disturbances along i t s p i t c h , yaw, and r o l l a x e s . A c o n t r o l l e r i s d e s i g n e d so t h a t t h e r o b o t c a n c a r r y o u t t a s k s with r e s p e c t t o t h e r o b o t b a s e frame. I n g e n e r a l , t h e p r o b l e m i s t o i n v e s t i g a t e the various modeling and c o n t r o l i s s u e s i n v o l v e d i n r o b o t i c s y s t e m s s u b j e c t e d t o t i m e v a r y i n g disturbances. I n t r o d u c t i o n T h e c o n t r o l o f m o b i l e r o b o t s h a s r e c e i v e d i n c r e a s e d a t t e n t i o n i n r e c e n t y e a r s . One problem t h a t m u s t b e c o n t e n d e d w i t h i s t h e e f f e c t s o f d i s t u r b a n c e s on t h e r o b o t . F o r a r o b o t s t a t i o n e d on a moving platform the disturbances are random i n n a t u r e and t h e c o n t r o l law must be a b l e t o m i n i m i z e t h e i r e f f e c t s . I n t h i s p a p e r , t h e r a n d o m d i s t u r b a n c e s a r e i n c o r p o r a t e d i n t o t h e d y n a m i c m o d e l o f t h e r o b o t s y s t e m . T h i s d e t e r m i n e s t h e f o r c e s a n d moments i n d u c e d b y t h e d i s t u r b a n c e s . A c o n t r o l l a w i s d e s i g n e d a n d t h e s y s t e m i s e x a m i n e d f o r s e v e r a l t a s k s . R e c o m m e n d a t i o n s a r e m a d e f o r t o r q u e r e q u i r e m e n t s a s w e l l a s t h e m e c h a n i c a l d e s i g n of the manipulator. Modeling of the Disturbance Consider a robot with two l i n k s m o u n t e d o n a p l a t f o r m . T h i s p l a t f o r m i s s u b j e c t e d t o random d i s t u r b a n c e s i n r o l l , p i t c h and yaw w i t h r e s p e c t t o a n i n e r t i a l f r a m e . The problem i s t o d e r i v e t h e p o i n t t o p o i n t c o n t r o l law. The robot i s shown i n Figure 1. The d i s t u r b a n c e c a n b e v i e w e d a s a t w i s t i n the robot base frame w i t h r e f e r e n c e t o t h e i n e r t i a l o r w o r l d f r a m e a t e v e r y i n s t a n t o f t i m e . H e n c e , i n s t a n t a n e o u s l y t h e r e e x i s t s a transformation which g i v e s t h e p o s i t i o n a n d o r i e n t a t i o n o f t h e r o b o t base with reference to the world frame.I n t u i t i v e l y , t h i s t r a n s f o r m a t i o n 111 i s r e p r e s e n t e d i n w o r l d c o o r d i n a t e s b y r o l l ( 6 ) about t h e 2 -a x i s , p i t c h (8) a b o u t t h e Y o -a x i s a n d yaw (Sa) a s o u t t h e X -a x i s . The o r d e r of r o t a t i o n i s . s p e c i f i e d a s RF'Y(6,9,Sa) = Rot(Zo,6) Bot(Yo,B) Rot(Xo,Q) (1) 0 Combining t h e r o t a t i o n s i n E q u a t i o n ( 1 ) y i e l d s t h e transformation L; CISM;ICQ cdseca+sdsn Rpy(b,e,Q) = sdce sdseso+cdc~ SdS~CQ-ClSQ cecQ 0 0 where Cy = cos 7 and Sy = s i n y. E v e n t h o u g ...

Black Soybean is highly nutritious legume of Uttarakhand but its hard seed coat reduces the nutrient availability to consumer. Attempt was made in this experiment to study effect of processing method on proximate composition of black soybean. Four Kilograms of black soybean was taken and subjected to three different processing methods like germination, roasting and cow urine treatment while one group was taken as control. Results indicated highly significant (P0.01) differences in dry matter, crude protein, ether extract, ash and crude fibre content of black soybean among different groups compared to control. All processing methods were effective in improving nutritional value of black soybean thereby increasing its utilization in foods and food formulations.

This paper formulates a maximum power point tracking (MPPT) technique that accurately tracks the maximum power point of photovoltaic (PV), which undergoes simultaneous or independent sudden changes in load resistance and irradiance. The proposed algorithm is fundamentally divided into three parts; current and voltage perturbation algorithm (IPA/VPA), perturbation step-size reduction algorithm (PSSRA) and a deviation avoidance loop. The use of dual perturbation parameters using IPA and VPA ensures high tracking speed. PSSRA iteratively reduces the perturbation step-size of IPA and VPA and helps in reducing the power oscillations around MPP. Finally, a deviation avoidance loop is developed to detect a change in irradiance by examining the sign of the slope of the two power curves, namely P-V and P-I. The algorithm compares the per unit change in voltage and current of PV, to determine a simultaneous change in both irradiance and load resistance. The proposed algorithm is compared with two recently developed MPPT algorithms. The results show that the proposed technique can track the MPP with high speed and low steady-state oscillations and does not deviate from the MPP tracking path regardless of fast changes in irradiance and load resistance.

Black Soybean is highly nutritious legume of Uttarakhand but its hard seed coat reduces the nutrient availability to consumer. Attempt was made in this experiment to study effect of processing method on proximate composition of black soybean. Four Kilograms of black soybean was taken and subjected to three different processing methods like germination, roasting and cow urine treatment while one group was taken as control. Results indicated highly significant (P0.01) differences in dry matter, crude protein, ether extract, ash and crude fibre content of black soybean among different groups compared to control. All processing methods were effective in improving nutritional value of black soybean thereby increasing its utilization in foods and food formulations.

Due to the high penetration of grid-connected photovoltaic (GCPV) systems, the network operators are regularly updating the grid codes to ensure that the operation of GCPV systems will assist in maintaining grid stability. Among these, low-voltage-ride-through (LVRT) is an important attribute of PV inverters that allows them to remain connected with the grid during short-term disturbances in the grid voltage. Hence, PV inverters are equipped with control strategies that secure their smooth operation through this ride-through period as per the specified grid code. During the injection of reactive power under LVRT condition, various challenges have been observed, such as inverter overcurrent, unbalance phase voltages at the point of common coupling (PCC), overvoltage in healthy phases, oscillations in active, reactive power and dc-link voltage, distortion in injected currents and poor dynamic response of the system. Several strategies are found in the literature to overcome these challenges associated with LVRT. This paper provides a critical review on the recent challenges and the associated strategies under LVRT conditions in GCPV inverters. The drawbacks associated with the conventional current control strategies are investigated in MATLAB/Simulink environment and each category of the advanced LVRT control strategy is analyzed under different types of grid faults. Moreover, this work categorizes different state-of-the-art LVRT techniques on the basis of synchronization methods, current injection techniques and dc-link voltage control strategies. It is found that the state-of-the-art control strategies like OVSS/OCCIDGS provides improved voltage support and current limitation which results in smooth LVRT operation by injecting currents of enhanced power quality.

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