This paper presents a novel low cost design for a 3-RRR Planar Parallel Manipulator (PPM). These manipulators proved their superiority over serial manipulators due to their speed, precision and smaller work space where the work space area is accounted for in the design to ensure that the robot is performing its task in a smooth and simple way without getting into any singularity points. The challenge with PPM is to obtain the kinematic constraint equations of the manipulator due to their complex non-linear behavior. Screw theory is a new approach that is used to compute the direct and inverse

Industrial dyes are considered one of the main causes of increased water pollution of water. Many businesses, such as steel and paper, are located along riverbanks because they require large amounts of water in their manufacturing processes, and their wastes, which contain acids, alkalis, dyes, and other chemicals, are dumped and poured into rivers as effluents. For example, chemical enterprises producing aluminum emit a significant quantity of fluoride into the air and effluents into water bodies. Fertilizer facilities produce a lot of ammonia, whereas steel plants produce cyanide. Many

A generalized structure for implementing fractional-order controllers is introduced in this paper. This is achieved thanks to the consideration of the controller transfer function as a ratio of integer and non-integer impedances. The non-integer order impedance is implemented using RC networks, such as the Foster and Cauer networks. The main offered benefit, with regards to the corresponding convectional implementations, is the reduced active and, also, passive component count. To demonstrate the versatility of the proposed concept, a controller suitable for implementing a cardiac pacemaker

With the end of Moore's law, new paradigms are investigated for more scalable computing systems. One of the promising directions is to examine the data representation toward higher data density per hardware element. Multiple valued logic (MVL) emerged as a promising system due to its advantages over binary data representation. MVL offers higher information processing within the same number of digits when compared with binary systems. Accessing memory is considered one of the most power- and time-consuming instructions within a microprocessor. In the quest for building an entire ternary

Systems without equilibrium such as electromechanical models with rotation and electrical circuits with cylindrical phase space were studied a long time ago. However, chaotic systems without equilibrium have received significant attention recently after the introduction of hidden attractors. Interestingly, an attractor of a no-equilibrium system is hidden because its basin of attraction does not intersect with any neighborhood of an unstable fixed point. This chapter presents a 3D no-equilibrium system with hidden chaotic attractors. The fundamental qualitative properties of the proposed no

An updated definition of group delay bandwidth in analog filters is introduced in this work. Unlike existing definitions, this new definition considers simultaneously the value of the group delay and filter gain, leading to minimized distortion in the filter output. In addition, it offers the capability of handling wide-band signals without introducing errors in the shape of their envelopes. Selected first- and second-order filters are studied and simulation results are provided to validate the efficiency of the new definition. © 2024 The Author(s). International Journal of Circuit Theory and

In this Letter we highlight some fundamental errors in the paper “Origin of the Curie–von Schweidler law and the fractional capacitor from time-varying capacitance” [J. Pow. Sources 532 (2022) 231309] by V. Pandey. In particular, with the use of the convolution integral of linear time-varying capacitance with the time-derivative of voltage (i.e. Eq (9) as suggested by the author), one ends up with step voltage function generating a constant current on a capacitive device, which is not true. We also question that a step voltage results in zero charge according to the r.h.s. of Eq. (9), but in

The exploitation of fractional calculus in engineering applications requires the utilization of fractional-order elements. As there is no immediate access to such type of elements, emulators that proportionally imitate their behavior are developed. The realization of emulators of fractional-order elements is based on the approximation of their impedance function. Subsequently, an advantageous option for the circuit implementation of the obtained, approximated impedance function is MOS transistor-based configurations, as they provide a dynamic system with electronically adjustable parameters

An attractive feature of fractional calculus is its application in various interdisciplinary fields, extending from biomedical and biological notions to mechanical properties. For their description, fractional-order models have outperformed the corresponding integer-order models, resulting in a more realistic behavior, due to the additional degrees of freedom offered and the long-term memory effect that reflects the fractional order. These improved features are processed by appropriate circuit implementations, derived through several approximation methods, whose primary objective is to provide

In this work, we generate and use a total of six different wideband signals for joint time-frequency characterization of nonlinear time-invariant [N-shaped differential resistor (NDR)] and linear time-varying (thermistor) circuits. A data acquisition board is used for applying the signals in the form of a voltage excitation and reading the induced current. The input signals have flat power spectra, thus avoiding the need for iterative calibration loops required to obtain signals with low crest factor. Such iterative loops are unavoidable when using random, pseudorandom, or chaotic signals all