The modeling and vibration analysis of a flexible manipulator considering a nonlinearity and effect from the gravity imply a singular problem. In order to avoid the singularity, the dynamic equation is decomposed into two subsystems, including flexible dynamic subsystem and rigid dynamic subsystem. A combined feed-forward and feedback control scheme is presented to design the controller of the flexible manipulator. In the combined control, an optimization is applied to obtain the desired trajectory based on the flexible dynamic subsystem. As we know, the optimization is dependent on the accuracy of model but there are inevitably errors of model and external disturbances. The feedback control is expected with high robustness and fast convergence to overcome the problem. In order to improve the performance of control, a hybrid sliding mode control (HySMC) is proposed to track the desired trajectory and further suppress the residual vibration. This paper presents the theoretical derivation and experimental verification of the proposed controller.

Proportional-Integral-Derivative (PID) control is widely used to control mechanical systems. In PID control technique, however, there are limits to the accuracy of the resulting movement because of the influence of gravity, friction, and interaction of joints caused by modeling errors. Digital acceleration control has robustness for the modeling errors. But it requires position, velocity, and acceleration of a controlled object to construct a controller. In this paper, we use the novel digital differentiator, ESDS. It enables digital acceleration control without increasing the number of sensors. Furthermore, the proposed method works effectively for quantized sensor data. The validity of the proposed method is confirmed by simulations and experiments using 2-link manipulator.

We develop a cyclogyro-based flying robot with a new variable attack angle mechanism. Cyclogyro is a flying machine which is supported in the air by power-driven rotors, which rotate about a horizontal axis, like the paddle-wheels of a steamboat. Machines of this type have been designed by some companies, but there is no record of any successful flights. The new variable attack angle mechanism proposed in this paper has an eccentric (rotational) point in addition to a rotational point connecting to a motor. The variable attack angle mechanism is a kind of double crank mechanism consisting of the two different rotational points and wings. The main feature of the mechanism with the eccentric point is to be able to change attack of angles according to the wing positions (according to the rotational angles of the cyclogyro) without actuators. The mechanism generates enough lift force to fly. We determine design parameters (wing span, the number of wings and eccentric distance) of the flying robot through experiments. Experimental results show that the developed cyclogyro-based flying robot with the new variable attack angle mechanism can hover along a vertical guide

The basic theoretical tool for a nonlinear filter estimating the smoothed value and the differential value from the data corrupted by impulsive noise at the ultrasonic sensors in our paper (Emaru and T. Tsuchiya, "Research on estimating smoothed value and differential value by using sliding mode system," IEEE Trans. Robot. Autom., vol. 19, no. 3, pp. 391-402, Jun. 2003) is the same as the theory proposed in the earlier paper by J. Q. Han and W. Wang (J. Q. Han and W. Wang, "Nonlinear tracking-differentiator" (in Chinese), J. Syst. Sci. Math. Sci., vol. 14, no. 2, pp. 177-183, 1994). Until now, we had not known the Journal of System Science and Mathematical Science (in Chinese), and had not read the paper listed in their comments. We should have cited their paper in our paper. We correct our failure of not citing their paper, and we sincerely apologize for our mistake.

To be able to recognize an environment, a robot should have as many sensors as possible. When we use sensors, we must consider the characteristics of the sensors, such as range, processing time, error, and so on. In this paper, we focus on the ultrasonic wave sensor that is today the most common sensor employed on indoor mobile robotic systems, and we propose a new technique for estimating the smoothed value and the differential value of the distances measured by the ultrasonic wave sensor. In proposing this system, we take the characteristics of the sensors mentioned above into consideration. In spite of the many methods proposed, it is still very difficult to eliminate the noise of sonar completely. Therefore, we smooth the distance value by assuming the continuity of the signal obtained by the sonar, and taking advantage of this continuity, we compose a robust estimator. The estimator is based on the sliding mode system.

To recognize an environment, the robot should have as many sensors as possible. When we use sensors, we must consider the characteristics of the sensors, such as range, processing time, error, and so on. We use an ultrasonic wave sensor that is today the most common technique employed on indoor mobile robotic systems, and we propose a technique to estimate the smoothed value and the differential value of the distance measured by the ultrasonic wave sensor. While proposing this system, we take the characteristics of the sensors mentioned above into consideration. In spite of the many methods proposed, it is still very difficult to eliminate the noise of sonar perfectly. So, we smooth the distance value by supposing the continuity of the signal that is obtained by the sonar, and taking advantage of this continuity, we compose a robust estimator. The estimator is based on a sliding mode system.