Masahiro Isogai

Locomotion mechanism and control method for a microrobot using the difference in the vibration characteristics of the legs (fabrication of a prototype microrobot; preliminary experiments and experiments in turning control)

Recently, microrobots have been the subject of a large number of studies, and contests are held throughout the year with the aim of developing microrobot technologies. As a result, various types of microrobots have been proposed including motor-type, piezoelectric-element-type, and electromagnet-type microrobots. This study considers a novel locomotion mechanism and a control method for an electromagnet-type microrobot that can not only travel in a straight line, but can also turn using just a single electromagnet that utilizes the difference in the vibration characteristics of the left and right legs. In this study, a control method to change the turning radius is proposed, and a prototype microrobot and controller are fabricated. In addition, the characteristics of the turning radius are investigated and the effectiveness of the proposed control method is verified through experiments.

Research on and education for navigation control of an exploration rover with microwave Doppler sensors (fabrication of the signal processing electrical circuit)

Microwave Doppler sensors commonly used in automatic-door systems have been used in a rover navigation system. A collimated microwave beam with an angular width of ±3° at a frequency of 24 GHz was emitted from a sensor (A) on a dish antenna 30 cm in diameter. Another sensor (B), which works as a detector, was installed on the rover. The rover was programmed to make a right turn when the microwave signal was above a specified level and to make a left turn when the signal was below that level. In this study, we fabricated a signal processing electrical circuit for the fourth prototype rover. To confirm the performance of the fabricated electrical circuit, we carried out some experiments on the frequency response of the electrical circuit. Finally, we had a questionnaire for the student who collaborated with this study to investigate how this study had an educational effect on the student.

Research on and education for navigation control of an exploration rover with microwave Doppler sensors

Microwave Doppler sensors commonly used in automatic-door systems have been used in a rover navigation system. A collimated microwave beam with an angular width of ±3° at a frequency of 24 GHz was emitted from a sensor (A) on a dish antenna 30 cm in diameter. Another sensor (B), which works as a detector, was installed on the rover. The rover was programmed to make a right turn when the microwave signal was above a specified level and to make a left turn when the signal was below that level. In this study, we fabricated the third prototype rover. To confirm the effectiveness of the proposed method, we performed the experiments on the strength distribution of the microwave beam and on the navigation control with the fabricated rover. Finally, we had a questionnaire for the student who collaborated with this study to investigate how the education effects for the student were.

Navigation control for an exploration rover with microwave Doppler sensors (Fabrication of third prototype rover and experiments)

Microwave Doppler sensors commonly used in automatic-door systems have been used in a rover navigation system. A collimated microwave beam with an angular width of ±3° at a frequency of 24 GHz was emitted from a sensor (A) on a dish antenna 30 cm in diameter. Another sensor (B), which works as a detector, was installed on the rover. The rover was programmed to make a right turn when the microwave signal was above a specified level and to make a left turn when the signal was than that level. In this study, we fabricated the third prototype rover. To confirm the effectiveness of the proposed method, we performed the experiments on the strength distribution of the microwave beam, and on the navigation control with the fabricated rover..

Navigation control for exploration rover with Microwave Doppler sensors

Microwave Doppler sensors commonly used in automatic-door systems have been used in a rover navigation system. A collimated microwave beam with an angular width of ±3° at a frequency of 24 GHz was emitted from a sensor (A) on a dish antenna 30 cm in diameter. Another sensor (B), which works as a detector, was installed on the rover. The rover was programmed to make a right turn when the microwave signal was above a specified level and to make a left turn when the signal was than that level. The rover started from a point 70 m away and approached to within 1.5 m of sensor A in 4-5 min. This navigation method is useful when GPS is not usable.

Locomotion mechanism and control method for a microrobot using the difference in the vibration characteristics of the legs (development of controller for experiments on frequency characteristics of running microrobot)

In recent years, various investigations have been conducted on microrobots by many researchers, and contests are held throughout the year with the aim of developing microrobot technologies. As a result, various types of microrobots have been proposed including motor-type, piezoelectric-element-type, and electromagnet-type microrobots. To date, the authors research group has been studying a locomotion mechanism and a control method for an electromagnet-type microrobot, which has a volume of 1cm3. In a previous study by the author, a structure and a control method that enable a microrobot with only one electromagnet coil to turn were proposed, and the characteristics of a running microrobot were investigated through some experiments. Here, theoretical confirmation of the effectiveness of the proposed method requires a mathematical model of the motion of the microrobot and some experiments with sinusoidal signals to indicate the validity of the mathematical model. So, the purpose of this paper is to develop experimental equipment including a controller which can generate sinusoidal signals. The basic function of the developed controller was confirmed through some experiments.