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Research on Internet-based teleoperation has received increased attention in the past few years. In this paper, an Internet-based teleoperation system was implemented. In order to robustly transmit the surroundings and control information of the robot, packet-type data were used. The central problem in Internet-based teleoperation is data transmission latency or data loss. For this specific problem, an autonomous mobile robot with optimal two-layer fuzzy controller (2LFC) was introduced. When data transmission is failed, the robot automatically moves and protects itself. In addition, a color detection system was implemented so that the robot can perceive an object and move to another object. The fuzzy controller was optimized by using the schema coevolutionary algorithm (SCEA), which finds an optimal solution. Using these technologies, the efficacies of the 2LFC, the SCEA, and the teleoperation system were verified

Researches on the design of the optimal fuzzy controller have been carried out for many years. Various approaches to fuzzy modeling have been proposed. In this paper, we introduce a novel algorithm, schema coevolutionary algorithm, for fuzzy modeling. We demonstrate the schema coevolutionary algorithm and compare it with other similar coevolutionary algorithms: virus-evolutionary genetic algorithm and coevolution of Handa. Then, we apply it to design the optimal fuzzy controller. The fuzzy controller is used to control the mobile robot and optimized by the schema coevolutionary algorithm. We verify the efficacy of this algorithm through the experiment and comparison with other algorithms.

In this letter, a new complementary Hartley (C-Hartley) voltage controlled oscillator (VCO) with fully differential outputs is proposed, in which the self-biasing configuration is introduced to solve the biasing difficulty of a Hartley VCO by employing a five-port transformer. The proposed C-Hartley VCO with the center frequency of 5.6 GHz is implemented in a 1P6M 0.18 μm CMOS process. The measurement result shows that the phase noise is -123.6 dBc/Hz at 1 MHz offset frequency, while dissipating 6.5 mA from 1.6 V supply with the FOM of -188.5 dBc.