A stiffness controllable multimodal whisker sensor follicle for texture comparison

Mammals like rats, who live in dark burrows, heav-ily depend on tactile perception obtained through the vibrissalsystem to move through gaps and to discriminate textures. Theorganization of a mammalian whisker follicle contains multiplesensory receptors and glands strategically organized to capturetactile sensory stimuli of different frequencies. In this paper, weused a controllable stiffness soft robotic follicle to test the hy-pothesis that the multimodal sensory receptors together with thecontrollable stiffness tissues in the whisker follicle form a physicalstructure to maximize tactile information. In our design, the ringsinus and ringwulst of a biological follicle are represented by alinear actuator connected to a stiffness controllable mechanismin-between two different frequency-dependent data capturingmodules. In this paper, we show for the first time the effectof the interplay between the stiffness and the speed of whiskingon maximizing a difference metric for texture classification

Fast spectral solutions of the double-gyre problem in a turbulent flow regime

Several semi-analytical models are considered for a double-gyre problem in a turbulent flow regime for which a reference fully numerical eddy-resolving solution is obtained. The semi-analytical models correspond to solving the depth-averaged Navier–Stokes equations using the spectral Galerkin approach. The robustness of the linear and Smagorinsky eddy-viscosity models for turbulent diffusion approximation is investigated. To capture essential properties of the double-gyre configuration, such as the integral kinetic energy, the integral angular momentum, and the jet mean-flow distribution, an improved semi-analytical model is suggested that is inspired by the idea of scale decomposition between the jet and the surrounding flow

Online Optimal Neuro-Fuzzy Flux Controller for DTC Based Induction Motor Drives

In this paper a fast flux search controller based on the Neuro-fuzzy systems is proposed to achieve the best efficiency of a direct torque controlled induction motor at light load. In this method the reference flux value is determined through a minimization algorithm with stator current as objective function. This paper discusses and demonstrates the application of Neurofuzzy filtering to stator current estimation. Simulation and experimental results are presented to show the fast response of proposed controller

Tapered whisker reservoir computing for real-time terrain identification-based navigation

This paper proposes a new method for real-time terrain recognition-based navigation for mobile robots. Mobile robots performing tasks in unstructured environments need to adapt their trajectories in real-time to achieve safe and efficient navigation in complex terrains. However, current methods largely depend on visual and IMU (inertial measurement units) that demand high computational resources for real-time applications. In this paper, a real-time terrain identification-based navigation method is proposed using an on-board tapered whisker-based reservoir computing system. The nonlinear dynamic response of the tapered whisker was investigated in various analytical and Finite Element Analysis frameworks to demonstrate its reservoir computing capabilities. Numerical simulations and experiments were cross-checked with each other to verify that whisker sensors can separate different frequency signals directly in the time domain and demonstrate the computational superiority of the proposed system, and that different whisker axis locations and motion velocities provide variable dynamical response information. Terrain surface-following experiments demonstrated that our system could accurately identify changes in the terrain in real-time and adjust its trajectory to stay on specific terrain

Control Space Reduction and Real-Time Accurate Modeling of Continuum Manipulators Using Ritz and Ritz-Galerkin Methods

To address the challenges with real-time accurate modeling of multi-segment continuum manipulators in the presence of significant external and body loads, we introduce a novel series solution for variable-curvature Cosserat rod static and Lagrangian dynamic method. By combining a modified Lagrange polynomial series solution, based on experimental observations, with Ritz and Ritz-Galerkin methods, the infinite modeling state space of a continuum manipulator is minimized to geometrical position of a handful of physical points (in our case two). As a result, a unified easy to implement vector formalism is proposed for the nonlinear impedance and configuration control. We showed that by considering the mechanical effects of highly elastic axial deformation, the model accuracy is increased up to 6%. The proposed model predicts experimental results with 6-8% (4-6 [mm]) mean error for the Ritz-Galerkin method in static cases and 16-20% (12-14 [mm]) mean error for the Ritz method in dynamic cases, in planar and general 3D motions. Comparing to five different models in the literature, our approximate solution is shown to be more accurate with the smallest possible number of modeling states and suitable for real-time modeling, observation and control applications

Utilization of poultry by product meal as an alternative protein source for Huso huso within growth period

With regard to increasing the fish meal price, utilization of hygienic and analyzed poultry by product meal as an alternative protein source in diets for Huso huso within growth period were investigated. Six test diets isonitrogenous and isocaleric (contain 42% protein and 20 Mj kg-1 energy) were prepared. Fish meal was substituted by poultry by product at 20% (PBM20), 40% (PBM40), 60% (PBM60), 80% (PBM80) and 100% (PBM100) in base diet, respectively. A total of 180 Huso huso with average (±SD) weight of 107.89±5.9gr were stocked in 18 fiberglass tanks (Voloum:2000 lit,Temperature:20±2C 0) and fed satiation to 18 weeks. No significant differences were detected between final weight (FW),weight gain (WG) and specific growth rate of fish fed (PBM0), (PBM20), (PBM40), (PBM60) and (PBM80) respectively. The Highest protein belonged to fish fed PBM20 (%16.97±0.36) with significant difference with PBM40 (% 15.41 ± 0.67), respectively. Body lipid fish fed PBM80 and PBM100 (%6.63±0.016) (%7.49±0.17) were significantly lower than other treatments. The Synchronic hepatosomatic index increased with increasing poultry by product in diets and highest rate were found in fish fed PBM 100 , but except PBM20, visceral index in fish fed other treatments was same. The result showed that up to 80% fish meal could be replaced by poultry by product with no adverse effect on growth and feed conversion ratio for Huso huso within growth period