Transient Analysis of Self-Powered Energy-Harvesting using Bond-Graph

Makihara, Kanjuro,Shigeta, Daisuke,Fujita, Yoshiyuki,Yamamoto, Yuta The Society for Aerospace System Engineering 2015 International Journal of Aerospace System Engineer Vol.2 No.1

The transient phenomenon of self-powered energy-harvesting is assessed using a bond-graph method. The bond-graph is an energy-based approach to describing physical-dynamic systems. It shows power flow graphically, which helps us understand the behavior of complicated systems in simple terms. Because energy-harvesting involves conversion of power in mechanical form to the electrical one, the bond-graph is a good tool to analyze this power flow. Although the bond-graph method can be used to calculate the dynamics of combining mechanical and electrical systems simultaneously, it has not been used for harvesting analysis. We demonstrate the usability and versatility of bond-graph for not only steady analysis but also transient analysis of harvesting.

Electrically-induced actuation for open-loop control to cancel self-excitation vibration

Makihara, Kanjuro,Ecker, Horst Techno-Press 2012 Smart Structures and Systems, An International Jou Vol.9 No.2

This paper focuses on the actuation system combined with a piezoelectric transducer and an electric circuit, which leads to a new insight; the electric actuation system is equivalent to mechanical variable-stiffness actuation systems. By controlling the switch in the circuit, the electric status of the piezoelectric transducer is changed, and consequently a variable-stiffness mechanism is achieved on the electric actuator. This proposed actuator features a shift in the equilibrium point of force, while conventional electrically-induced variable-stiffness actuators feature the variation of the stiffness value. We intensively focus on the equilibrium shift in the actuation system, which has been neglected. The stiffness of the variable-stiffness actuator is periodically modulated by controlling the switch, to suppress the vibration of the system in an open-loop way. It is proved that this electric actuator is equivalent to its mechanical counterpart, and that the electrical version has some practical advantages over the mechanical one. Furthermore, another kind of electrically-induced variable-stiffness actuator, using an energy-recycling mechanism is also discussed from the viewpoint of open-loop vibration control. Extensive numerical simulations provide comprehensive assessment on both electrically-induced variable-stiffness actuators employed for open-loop vibration control.

Energy-efficiency enhancement and displacement-offset elimination for hybrid vibration control

Makihara, Kanjuro Techno-Press 2012 Smart Structures and Systems, An International Jou Vol.10 No.3

New insights into our previously proposed hybrid-type method for vibration control are highlighted in terms of energy analysis, such as the assessment of energy efficiency and system stability. The hybrid method improves the bang-bang active method by combining it with an energy-recycling approach. Its simple configuration and low energy-consumption property are quite suitable especially for isolated structures whose energy sources are strictly limited. The harmful influence of the external voltage is assessed, as well as its beneficial performance. We show a new chattering prevention approach that both harvests electrical energy from piezoelectric actuators and eliminates the displacement-offset of the equilibrium point of structures. The amount of energy consumption of the hybrid system is assessed qualitatively and is compared with other control systems. Experiments and numerical simulations conducted on a 10-bay truss can provide a thorough energy-efficiency evaluation of the hybrid suppression system having our energy-harvesting system.

Flutter Suppression of Cantilevered Plate Wing using Piezoelectric Materials

Makihara, Kanjuro,Onoda, Junjiro,Minesugi, Kenji The Korean Society for Aeronautical and Space Scie 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2

The supersonic flutter suppression of a cantilevered plate wing is studied with the finite element method and the quasi-steady aerodynamic theory. We suppress wing flutter by using piezoelectric materials and electric devices. Two approaches to flutter suppression using piezoelectric materials are presented; an energy-recycling semi-active approach and a negative capacitance approach. To assess their flutter suppression performances, we simulate flutter dynamics of the plate wing to which piezoelectric patches are attached. The critical dynamic pressure drastically increases with our flutter control using a negative capacitor.

Flutter Suppression of Cantilevered Plate Wing using Piezoelectric Materials

Kanjuro Makihara,Junjiro Onoda,Kenji Minesugi 한국항공우주학회 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2

The supersonic flutter suppression of a cantilevered plate wing is studied with the finite element method and the quasi-steady aerodynamic theory. We suppress wing flutter by using piezoelectric materials and electric devices. Two approaches to flutter suppression using piezoelectric materials are presented; an energy-recycling semi-active approach and a negative capacitance approach. To assess their flutter suppression performances, we simulate flutter dynamics of the plate wing to which piezoelectric patches are attached. The critical dynamic pressure drastically increases with our flutter control using a negative capacitor.

Electrically-induced actuation for open-loop control to cancel self-excitation vibration

Kanjuro Makihara,Horst Ecker 국제구조공학회 2012 Smart Structures and Systems, An International Jou Vol.9 No.2

This paper focuses on the actuation system combined with a piezoelectric transducer and an electric circuit, which leads to a new insight; the electric actuation system is equivalent to mechanical variablestiffness actuation systems. By controlling the switch in the circuit, the electric status of the piezoelectric transducer is changed, and consequently a variable-stiffness mechanism is achieved on the electric actuator. This proposed actuator features a shift in the equilibrium point of force, while conventional electricallyinduced variable-stiffness actuators feature the variation of the stiffness value. We intensively focus on the equilibrium shift in the actuation system, which has been neglected. The stiffness of the variable-stiffness actuator is periodically modulated by controlling the switch, to suppress the vibration of the system in an open-loop way. It is proved that this electric actuator is equivalent to its mechanical counterpart, and that the electrical version has some practical advantages over the mechanical one. Furthermore, another kind of electrically-induced variable-stiffness actuator, using an energy-recycling mechanism is also discussed from the viewpoint of open-loop vibration control. Extensive numerical simulations provide comprehensive assessment on both electrically-induced variable-stiffness actuators employed for open-loop vibration control.

Self-reliant wireless health monitoring based on tuned-mass-damper mechanism

Kanjuro Makihara,Hidekazu Hirai,Yuta Yamamoto,Hisao Fukunaga 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.6

We propose an electrically self-reliant structural health monitoring (SHM) system that is able to wirelessly transmit sensing data using electrical power generated by vibration without the need for additional external power sources. The provision of reliable electricity to wireless SHM systems is a highly important issue that has often been ignored, and to expand the applicability of various wireless SHM innovations, it will be necessary to develop comprehensive wireless SHM devices including stable electricity sources. In light of this need, we propose a new, highly efficient vibration-powered generator based on a tuned-mass-damper (TMD) mechanism that is quite suitable for vibration-based SHM. The charging time of the TMD generator is shorter than that of conventional generators based on the impedance matching method, and the proposed TMD generator can harvest 16 times the amount of energy that a conventional generator can. The charging time of an SHM wireless transmitter is quantitatively formulated. We conduct wireless monitoring experiments to validate a wireless SHM system composed of a self-reliant SHM and a vibration-powered TMD generator.

Energy-efficiency enhancement and displacement-offset elimination for hybrid vibration control

Kanjuro Makihara 국제구조공학회 2012 Smart Structures and Systems, An International Jou Vol.10 No.3

New insights into our previously proposed hybrid-type method for vibration control are highlighted in terms of energy analysis, such as the assessment of energy efficiency and system stability. The hybrid method improves the bang-bang active method by combining it with an energy-recycling approach. Its simple configuration and low energy-consumption property are quite suitable especially for isolated structures whose energy sources are strictly limited. The harmful influence of the external voltage is assessed, as well as its beneficial performance. We show a new chattering prevention approach that both harvests electrical energy from piezoelectric actuators and eliminates the displacement-offset of the equilibrium point of structures. The amount of energy consumption of the hybrid system is assessed qualitatively and is compared with other control systems. Experiments and numerical simulations conducted on a 10-bay truss can provide a thorough energy-efficiency evaluation of the hybrid suppression system having our energy-harvesting system.

Stabilized Finite Element Scheme for the Navier-Stokes Equation

Takafumi Makihara,Etsutaro Shibata,Takahiko Tanahashi 대한기계학회 1998 KSME/JSME THERMAL and FLUID Engineering Conference Vol.1 No.1

Homogeneous Quantitative Measure of Caging Grasps with both Geometrical and Mechanical Constraints

Satoshi Makita,Koshi Makihara 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

This paper presents a homogeneous evaluation of difficulty of moving attributed to both geometrical and mechanical constraints. Although caging grasp usually considers to confine an object geometrically by surrounding robots, it is not always feasible due to limitation of robots such as few number of robots or fingers. Such incomplete caging is often called as partial caging, and in which the object can escape from the cage of robots. And then the object is prevented from moving by both geometrical constraints and mechanical effects. The former can be discussed with arrangements of robots and environments, and the latter is investigated with static/dynamic analyses of contact forces. This paper addresses both different indexes homogeneously based on robustness measure for grasping and contact tasks. We introduce a novel interpretation for evaluation of complete/partial caging quality, and show some numerical examples.