MICROSCOPIC THRUSTERS PROVIDING THE PROPULSION FOR THE MINIATURE ROCKETS

A flat, compact square, much like a computer chip, the device was designed by paulo lozano, an associate professor of aeronautics and astronautics at the Massachusetts Institute of Technology. The device is covered with five hundred microscopic tips that, when stimulated with voltage, emit minute beams of ions. A satellite the size of a shoebox may be moved forward with the aid of a little puff of charged particles that are produced when the array of spiky points is brought together. This design is not even somewhat comparable to the cumbersome satellite engines that are used today. Those engines are full of valves, pipelines, and huge propellant tanks. Micro-manufacturing processes are used for the production of miniature ion thrusters. This graphic provides an illustration of some of the many components that make up a thruster. The finished product can be seen in the lower right corner and has dimensions of 1 centimeter by 1 centimeter with a thickness of 2 millimeters. picture by M. Scott Brauer; credit due to him. Lozano stated in a statement that “[the microthrusters] are so tiny that you can place numerous [thrusters] on a vehicle.” Additionally, he said that a tiny satellite that was equipped with a number of microthrusters might “not only move to adjust its orbit, but also do other exciting things—like turn and roll.” At the most recent joint propulsion conference hosted by the American Institute of Aeronautics and Astronautics, lozano and his team from the space propulsion laboratory and the microsystems technology laboratory at mit presented their newly developed thruster array. Lozano’s idea for a microthruster contributes very little to the total weight of a satellite. The microchip is made up of many layers of porous metal, with the top layer having a surface that is textured with five hundred metallic points that are uniformly spaced apart. The functioning of the device is dependent on the presence of a tiny reservoir of liquid, referred to as a “liquid plasma” of free-floating ions, which is located at the very bottom of the chip. Lozano used the analogy of a tree to illustrate how the thruster works. Water from the ground is drawn up a tree by a sequence of smaller and smaller pores, beginning in the roots, then moving up the trunk, and eventually passing through the leaves, where sunlight evaporates the water as gas. Lozano’s microthruster works by a process that is analogous to that of capillary action: each layer of metal includes holes that are progressively smaller, which allow the ionic liquid to be drawn upwards through the chip and to the tops of the metallic points. The team constructed a plate with a gold coating to put over the chip, and then they applied a voltage to generate an electric field between the plate and the tips of the thrusters. Consequently, beams of ions exited from the tips, causing a push to be generated. An array of 500 points creates 50 micronewtons of force, which is a level of push that, on earth, could barely hold a little shred of paper. This was discovered by the researchers. But in the microgravity environment of space, this little force would be enough to push a spacecraft weighing two pounds. In addition, lozano and co-author of the eth study dan courtney discovered that very modest changes in voltage caused a huge rise in force among the thruster’s 500 tips. This finding is encouraging in terms of the thruster’s ability to make efficient use of energy. a useful website is available at http://nipun-frendshipspot.blogspot.in.