Microwave power for smart material actuators

Abstract

The concept of microwave-driven smart material actuators was envisioned and developed as the best option to alleviate the complexity and weight associated with a hard-wire-networked power and control system for smart actuator arrays. The patch rectenna array was initially designed for high current output, but has undergone further development for high voltage output devices used in shape control applications. Test results show that more than 200 V of output were obtained from a 6 × 6 array at a far-field exposure (1.8 m away) with an X-band input power of 18 W. The 6 × 6 array patch rectenna was designed to theoretically generate voltages up to 540 V, but practically it has generated voltages in the range between 200 and 300 V. Testing was also performed with a thin layer composite unimorph ferroelectric driver and sensor and electro-active paper as smart actuators attached to the 6 × 6 array. Flexible dipole rectenna arrays built on thin-film-based flexible membranes are most applicable for NASA's various missions, such as microwave-driven shape controls for aircraft morphing and large, ultra-lightweight space structures. An array of dipole rectennas was designed for high voltage output by densely populating Schottky barrier diodes to drive piezoelectric or electrostrictive actuators. The dipole rectenna array will eventually be integrated with a power allocation and distribution logic circuit and microbatteries for storage of excessive power. The roadmap for the development of wireless power drivers based on the rectenna array for shape control requires the development of new membrane materials with proper dielectric constants that are suitable for dipole rectenna arrays.

Energy Harvesting for Structural Health Monitoring Sensor Networks

“…With the use of rectennas (rectifying-antenna) that integrates the technology to receive and to directly convert the microwaves into DC power, efficiencies in the 50%-80% range have been achieved. Significant testing has also been done across long distances and with kW power levels [ 77 ]. Briles et al [ 78 ] invented a RF wireless energy delivery system for underground gas or oil recovery pipes.…”

Review of radio wave for power transmission in medical applications with safety

“…Since Nicola Tesla suggested an idea of wireless power transmission (WPT) and carried out the first wireless power transmission experiment in 1899 [1][2], WPT technology has been developed and used in many practical applications such as solar satellite [3][4], smart actuators [5][6][7][8][9], space and air vehicles [10][11][12][13], and other medical applications [14][15][16][17][18][19][20]. Microwave technology in medicine has been used for therapeutic purpose [21], detection [22], and power sources for medical devices in human body [23,24].…”

Wireless actuation and control of ionic polymer–metal composite actuator using a microwave link

“…A long-endurance, high-altitude platform known as SHARP (stationary high-altitude relay platform) receives power from a large array of antennas on the ground [19]. Compared to the above, high-power transmission applications and also a weak-power transmission using a flexible rectenna have been researched [20][21][22]. The flexible dipole rectenna arrays, built on thin film based flexible membranes, provides the power to the other smart material actuator.…”