Design and Implementation of Robofly Wing Flapping Mechanism Using Piezoelectric Crystal

Micromechanical Flying Insect (MFI) or simply ‘robofly’ is a newly introduced air vehicle which is tiny and maneuverable. It is a project requiring collaboration from several academic areas such as biology, robotics and engineering. The target robotic insects are electromechanical devices propelled by a pair of independent flapping wings to achieve sustained autonomous flight, thereby mimicking real insects. Part of the research involves trying to figure out how insects, and specifically flies, flap their wings with high speed and intensity. Initiation stage of this project was to conduct thorough study and research on the robofly. Considering high frequency of flapping motion, robofly is best actuated by piezoelectric ceramics. The direct piezoelectric effect is that piezo ceramic generates an electrical charge during mechanical distortion or load. During an inverse piezoelectric effect the piezoceramic body changes under the influence of an electrical field. The Piezoelectric effect can occur under the influence of external forces. Depending on the force direction electrical charges with corresponding polarity are generated. An inverse piezoelectric effect takes place under the influence of electrical fields. The body changes its dimension along with the change of voltage. The main objective of this project is mainly the design of the thorax structure for robofly and it is defined as the most critical part during this project ongoing. The most efficient method for the robofly to take off into the air is to design a flapping mechanism actuated by piezoelectric. Using a four bar linkage, small piezoelectric linear displacement can be converted to rotational wing motion at high frequency. Solid model design and motion simulation has been generated for both options. The output from both designs are to be compared and the best output in terms of wing stroke angle being picked as best design

Design and Implementation of Robofly Wing Flapping Mechanism Using Piezoelectric Crystal

Micromechanical Flying Insect (MFI) or simply ‘robofly’ is a newly introduced air vehicle which is tiny and maneuverable. It is a project requiring collaboration from several academic areas such as biology, robotics and engineering. The target robotic insects are electromechanical devices propelled by a pair of independent flapping wings to achieve sustained autonomous flight, thereby mimicking real insects. Part of the research involves trying to figure out how insects, and specifically flies, flap their wings with high speed and intensity. Initiation stage of this project was to conduct thorough study and research on the robofly. Considering high frequency of flapping motion, robofly is best actuated by piezoelectric ceramics. The direct piezoelectric effect is that piezo ceramic generates an electrical charge during mechanical distortion or load. During an inverse piezoelectric effect the piezoceramic body changes under the influence of an electrical field. The Piezoelectric effect can occur under the influence of external forces. Depending on the force direction electrical charges with corresponding polarity are generated. An inverse piezoelectric effect takes place under the influence of electrical fields. The body changes its dimension along with the change of voltage. The main objective of this project is mainly the design of the thorax structure for robofly and it is defined as the most critical part during this project ongoing. The most efficient method for the robofly to take off into the air is to design a flapping mechanism actuated by piezoelectric. Using a four bar linkage, small piezoelectric linear displacement can be converted to rotational wing motion at high frequency. Solid model design and motion simulation has been generated for both options. The output from both designs are to be compared and the best output in terms of wing stroke angle being picked as best design

Piezoelectric actuator for micro robot used in nanosatellite

The nanosatellites of the CubeSat standard (10×10×10 cm and with mass 1-10 kg) was designed to reduce cost and development time and to maximize science return. However, the small size of the spacecraft imposes substantial mass, volume, and power constraints. The challenge remains to be the miniaturization of the various robots for the manipulation of functional objects, such as cameras, laser sources, mirrors and other used in nanosatellites. Therefore in particular, precision positioning of the manipulated object is important task for robots used in nanosatellites as well. In this paper authors present the design of robot driven by the piezoelectric actuators. Investigations of the robot are presented and they prove ability to improve the accuracy of the movement for the robot arm using two bending bimorph type piezoelectric actuators and 3DOF rotary piezoelectric motor

Investigation of motion control of piezoelectric unimorph for laser shutter systems

This paper presents the design and testing of a resonance frequency-tunable piezoelectric unimorph chopper and shutter that employ a magnetic force technique and magnetorheological fluid (MRF). This technique enabled to increase the frequency of the resonance up to 110% of the untuned resonant frequency. A piezoelectric unimorph cantilever with a natural frequency of 126 Hz is used as the laser beam chopper or shutter, which is successfully tuned in a frequency range of 126 - 270 Hz thereby enabling continuous control of the laser beam over the entire frequency range tested. A theoretical model based on variable magnetic field strength and MRF damping is presented. The magnetic force and MRF applied for damping of transient vibrations of the piezoelectric unimorph shutter have been experimentally determine

Robust Control of Flapping-Wing in Micro Aerial Vehicle to have a Smooth Flapping Motion

This paper in first sections, will give a brief overview of both the purpose and the challenges facing the actuator and structure of Micromechanical Flying Insects (MFIs) and, in the last sections, an appropriate controller will developed for flapping motion. A hierarchical architecture that divides the control unit into three main levels is introduced. This approach break a complex control problem into a multi-level set of smaller control schemes, each of which is responsible for a clearly defined task. Also, the controller at each level can be designed independently of those in other levels. A fourbar mechanism for the wing displacement amplification, and a new system for fourbar mechanism actuation (wing actuation) is developed. We will develop a flexible beam with piezoelectric actuators and sensor (called Smart Beam) that will used to excite the fourbar mechanism for flapping mode of flight. The Frequency Response Function (FRF) of the smart beam was obtained from a Finite Element (FE) model and experimental system identification. The corresponding transfer function was derived from the mu synthesis and several robust controllers were then designed to control the beam to reach a smooth flapping motion. Besides excitation of the fourbar mechanism, the Smart beam will be used to control of noise and disturbance in the structure of the wing system

Investigation of novel design piezoelectric bending actuators

Two piezoelectric bending actuators of a novel design are presented and analysed in the paper. Numerical modelling and experimental study of the piezoelectric bending actuators were performed to verify operating principle and to investigate dynamic characteristics of the actuators. Numerical calculations are performed by using finite element method. Results of experimental study of piezoelectric actuators are compared with the results of finite element simulations. Results of the numerical and experimental research are analysed and discussed

Investigation of motion control of piezoelectric unimorph for laser shutter systems

This paper presents the design and testing of a resonance frequency-tunable piezoelectric unimorph chopper and shutter that employ a magnetic force technique and magnetorheological fluid (MRF). This technique enabled to increase the frequency of the resonance up to 110% of the untuned resonant frequency. A piezoelectric unimorph cantilever with a natural frequency of 126 Hz is used as the laser beam chopper or shutter, which is successfully tuned in a frequency range of 126 - 270 Hz thereby enabling continuous control of the laser beam over the entire frequency range tested. A theoretical model based on variable magnetic field strength and MRF damping is presented. The magnetic force and MRF applied for damping of transient vibrations of the piezoelectric unimorph shutter have been experimentally determine

Investigation of motion control of piezoelectric unimorph for laser shutter systems

This paper presents the design and testing of a resonance frequency-tunable piezoelectric unimorph chopper and shutter that employ a magnetic force technique and magnetorheological fluid (MRF). This technique enabled to increase the frequency of the resonance up to 110% of the untuned resonant frequency. A piezoelectric unimorph cantilever with a natural frequency of 126 Hz is used as the laser beam chopper or shutter, which is successfully tuned in a frequency range of 126 - 270 Hz thereby enabling continuous control of the laser beam over the entire frequency range tested. A theoretical model based on variable magnetic field strength and MRF damping is presented. The magnetic force and MRF applied for damping of transient vibrations of the piezoelectric unimorph shutter have been experimentally determine