A robust adaptive controller for PM motor drives in roboticapplications

The paper deals with theoretical development and practical implementation of an adaptive speed and position regulator suitable for robotic applications. The proposed adaptive control scheme is characterized by a reduced amount of computation and is based on the model reference adaptive control approach to compensate the variations of the system parameters, such as inertia and torque constant. A disturbance torque observer is employed to balance the required load torque and reduce the complexity of the adaptive algorithm. Simulation tests of a robotic drive, including an interior type permanent magnet synchronous (IPMS) motor, are reported in order to compare the proposed control scheme with standard speed and position regulators. Experimental results, obtained from a prototype based on a commercial PC board, are also reported in order to practically evaluate the feasibility and the features of the proposed adaptive control scheme     

Evaluation of a Modified pH‐Shift Process to Reduce 2‐Methylisoborneol and Geosmin in Spiked Catfish and Produce a Consumer Acceptable Fried Catfish Nugget‐Like Product

Abstract: Muddy and/or musty off‐flavors in farmed‐raised catfish occur as a result of the absorption of geosmin (GEO) and 2‐methylisoborneol (MIB), compounds produced by algae. Previous research suggests the acid pH‐shift method may be able to reduce off‐flavors to produce a consumer acceptable product. The objective of this research was to evaluate application of the acid pH‐shift method using a shaker sieve for protein recovery and to evaluate consumer acceptability of a resultant batter‐coated fried nugget‐like catfish product. Farm‐raised catfish were either allowed to depurate (control) or treated with 1 ppb GEO or MIB. Fillets from each replicate were collected and ground and treated by the acid pH‐shift process. Samples from all treatments and replicates were evaluated for residual GEO and MIB. In addition, batter‐coated fried catfish samples were prepared for a consumer sensory evaluation. Results demonstrated that the pH‐shift process decreased moisture, ash, and collagen content of catfish fillet tissue (P < 0.05). Flavor of control samples was preferred (P < 0.05). Texture of catfish samples treated by the pH‐shift process was preferred (P < 0.05). Results demonstrate the pH‐shift process can be utilized to reduce off‐flavors and increase the acceptability of a processed catfish product. Practical Application: Use of a sieve as an economic alternative for the pH‐shift process was evaluated for removing off‐flavors from catfish. Difficulties were encountered with regard to protein recovery using the sieve and suggestions are made to, perhaps, make the process more applicable for a sieve‐based recovery step. The process as described reduced off‐flavors, but only 2‐fold suggesting the process would work best on catfish near or just over off‐flavor thresholds. Results also indicated the pH‐shift process could be used to improve texture of a fried catfish product designed to be similar to chicken nuggets.     

Fuzzy adaptive vector control of induction motor drives

This paper deals with the design and experimental realization of a model reference adaptive control (MRAC) system for the speed control of indirect field-oriented (IFO) induction motor drives based on using fuzzy laws for the adaptive process and a neuro-fuzzy procedure to optimize the fuzzy rules. Variation of the rotor time constant is also accounted for by performing a fuzzy fusion of three simple compensation strategies. A performance comparison between the new controller and a conventional MRAC control scheme is carried out by extensive simulations confirming the superiority of the proposed fuzzy adaptive regulator. A prototype based on an induction motor drive has been assembled and used to practically verify the features of the proposed control strategy