This paper proposes a novel fuzzy-adaptive extended Kalman filter (FAEKF) for the real-time attitude estimation of agile mobile platforms equipped with magnetic, angular rate, and gravity (MARG) sensor arrays. The filter structure employs both a quaternion-based EKF and an adaptive extension, in which novel measurement methods are used to calculate the magnitudes of system vibrations, external accelerations, and magnetic distortions. These magnitudes, as external disturbances, are incorporated into a sophisticated fuzzy inference machine, which executes fuzzy IF-THEN rules-based adaption laws to consistently modify the noise covariance matrices of the filter, thereby providing accurate and robust attitude results. A six-degrees of freedom (6 DOF) test bench is designed for filter performance evaluation, which executes various dynamic behaviors and enables measurement of the true attitude angles (ground truth) along with the raw MARG sensor data. The tuning of filter parameters is performed with numerical optimization based on the collected measurements from the test environment. A comprehensive analysis highlights that the proposed adaptive strategy significantly improves the attitude estimation quality. Moreover, the filter structure successfully rejects the effects of both slow and fast external perturbations. The FAEKF can be applied to any mobile system in which attitude estimation is necessary for localization and external disturbances greatly influence the filter accuracy.The MEMS inertial measurement unit (IMU), composed of tri-axis MEMS accelerometer, gyroscope, and magnetometer sensors, also known as the measurement system of magnetic, angular rate, and gravity (MARG) sensor arrays, is the most commonly utilized device to track the real-time orientation of mobile platforms at present. The low-cost, low power consumption, and small size characteristics meet technological requirements, and therefore these devices have been widely utilized in embedded systems, where the filtering algorithm is executed by a microprocessor. As a result, an attitude and heading reference system (AHRS) has been formed, which provides the complete orientation measurement relative to the Earth's gravitational and magnetic fields (global reference system), where the attitude denotes the roll and pitch angles, whereas heading refers to the yaw Euler angle [19]. The role of the aforementioned filtering algorithm is to combine the individual features of each sensor and provide both properly smoothed and robust attitude results with regard to the global reference system, in either Euler angles or quaternions. The most common method applied in sensor fusion techniques synthesizes the short-term accuracy of gyroscope-based attitude realizations and the accelerometer and magnetometer provide rough, low-frequency attitude corrections. This technique cancels the accumulated error (drift), smooths the signals, and produces long-term stable outputs if the IMU is in stationary states. Significant decrease in estimation performance arises when...

The rat's prefrontal cortex plays a role in integration of feeding-related information. In this study, we investigated the neuronal activity changes of medial prefrontal cortex during licking of sucrose solution by freely moving rats. We found two different types of excitatory and two different types of inhibitory single neuron responses time locked to the beginning of the licking clusters. Changes in firing rates occurred either within 2 s before the first lick of the licking cluster or during the licking cluster. These observations suggest that neuronal responses in the medial prefrontal cortex may represent anticipation and consummation of liquid food reward.

The utilization of stereo cameras in robotic applications is presented in this paper. The use of a stereo depth sensor is a principal step in robotics applications, since it is the first step in sequences of robotic actions where the intent is to detect and extract windows and obstacles that are not meant to be painted from the surrounding wall. A RealSense D435 stereo camera was used for surface recording via a real-time, appearance-based (RTAB) mapping procedure, as well as to navigate the painting robot. Later, wall detection and the obstacle avoidance processes were performed using statistical filtering and a random sample consensus model (RANSAC) algorithm.

Sleep and local field potential (LFP) characteristics were addressed during the reproductive cycle in female rats using long-term (60–70 days) recordings. Changes in homeostatic sleep regulation was tested by sleep deprivation (SDep). The effect of mother-pup separation on sleep was also investigated during the postpartum (PP) period. First half of the pregnancy and early PP period showed increased wakefulness (W) and higher arousal indicated by elevated beta and gamma activity. Slow wave sleep (SWS) recovery was suppressed while REM sleep replacement was complete after SDep in the PP period. Pup separation decreased maternal W during early-, but increased during middle PP while did not affect during late PP. More W, less SWS, higher light phase beta activity but lower gamma activity was seen during the post-weaning estrus cycle compared to the virgin one. Maternal sleep can be governed by the fetuses/pups needs and their presence, which elevate W of mothers. Complete REM sleep- and incomplete SWS replacement after SDep in the PP period may reflect the necessity of maternal REM sleep for the offspring while SWS increase may compete with W essential for maternal care. Maternal experience may cause sleep and LFP changes in the post-weaning estrus cycle.

Serious efforts have been made to develop anxiolytics with improved clinical utility and reduced side effects. 5-Hydroxytryptamine (5-HT) 2C receptor antagonists are potential anxiolytics; however, their effects on vigilance are not well characterized. To compare the effects of benzodiazepines and subtype-selective 5-HT 2C receptor antagonists on anxiety, vigilance, and electroencephalogram (EEG) power density, social interaction test and polygraphic recordings were performed in male Sprague-Dawley rats after chlordiazepoxide (CDP; 4.0 mg/kg i.p.) and SB-242084 (6-chloro-5-methyl-1-[2-(2-methylpyrid-3-yloxy)-pyrid-5-yl carbamoyl] indoline) (0.1, 0.3, and 1.0 mg/kg i.p.) treatment. CDP and SB-242084 (0.3 and 1.0 mg/kg) had similar anxiolytic effects. Spectral analysis of EEG in wakefulness (W) and paradoxical sleep (PS) showed an opposite effect on activity (5-9 Hz); it decreased after CDP, whereas it increased after SB-242084 (even at 0.1 mg/kg). In addition, CDP significantly decreased slow-wave activity (0.5-4 Hz) in deep slow-wave sleep (SWS-2) and increased power at frequencies above 12 Hz mainly in W and PS. A markedly increased intermediate stage of sleep was also found after CDP treatment. At the highest dose, SB-242084 increased W and decreased SWS-2. In summary, low but potent anxiolytic doses of the subtype-selective 5-HT 2C receptor antagonist SB-242084 did not affect vigilance states but caused an increased activity in W, raising the possibility of a cognitive-enhancing effect of the drug. In contrast, acute CDP administration, based on spectral analysis of the EEG, produced a more superficial sleep along with a decreased activity.Efforts to improve the clinical utility and reduce the side effects of classic benzodiazepines have a long history (Haefely et al., 1992). Although the anxiolytic properties of these drugs are well established both clinically and experimentally (Argyropoulos and Nutt, 1999;File and Seth, 2003), the side effects like impaired short-term memory, vigilance, or psychomotor performance limit their clinical applicability (Kunsman et al., 1992;van Laar et al., 2001;Buffett-Jerrott and Stewart, 2002). On the other hand, these effects are often subtle when low doses are involved (Kunsman et al., 1992), and tolerance develops to the sedative and psychomotor effects with their continued use as anxiolytics (Lucki et al., 1986).Pharmacological characterization of the effects of the

This review paper presents an overview of depth cameras. Our goal is to describe the features and capabilities of the introduced depth sensors in order to determine their possibilities in robotic applications, focusing on objects that might appear in applications with high accuracy requirements. A series of experiments was conducted, and various depth measuring conditions were examined in order to compare the measurement results of all the depth cameras. Based on the results, all the examined depth sensors were appropriate for applications where obstacle avoidance and robot spatial orientation were required in coexistence with image vision algorithms. In robotic vision applications where high accuracy and precision were obligatory, the ZED depth sensors achieved better measurement results.

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