Flight Rail's Engineering Manager, M. Eric Schlienger Ph.D., with intern Luke Robinson installing automated controls on the 1/6 scale pilot model blower/changeover valve system.
Recent advances in the Flight Rail pilot scale model include improved utilization of pumping energy. The initial proof of concept design operated with one side of the thrust carriage subjected to vacuum (or pressure), with the other side open to atmosphere. This represents a condition that will be commonly observed during full sized implementation, but does not take into account optimal energy utilization as the VECTORR unit passes a pumping station. On our test system when the unit (actually the thrust valve) passes the pumping station, the pumping station switches from pulling the unit (vacuum) to pushing the unit (pressure). For our initial trials, at the transition from vacuum to pressure modes of operation, the valve at the open end of the power tube would close, and the valve at the closed end would open. These valve motions support the transition of the operating mode from vacuum to pressure. However, our initial valve timing, (wherein the valve motion occurs as the thrust valve passes the pumping station inlet), does not take into account the loss of energy associated with the opening to atmosphere of the already evacuated portion of the power tube in advance of the thrust carriage. A new sensor suite, developed using Arduino boards by our summer intern Luke Robinson, has been added to provide accurate thrust carriage position sensing and precise pressure monitoring of the power tube. With the new position sensors in place, we are able to accurately gauge the timing of the transitions between vacuum and pressure at each of our inlet ports. The addition of the precision differential pressure sensors provide the ability to delay the opening of the power tube to atmosphere until the usable accumulated vacuum energy in front of the thrust carriage has been expended in the production of additional thrust. As a side benefit, the position sensors also provide velocity data. The combination of these sensors results in a smoother modal transition, a more uniform thrust profile and better energy utilization. We see this as a very positive development in the demonstration of the real world application of this technology.
Luke graduated from Ukiah High School last Spring and will be starting at Johns Hopkins University in the fall. His expertise is in electronics. As a freshman there he will be studying computer engineering. For three summers as a high school student, he has offered a camp for middle-school students on basic robotics using the Arduino development platform. These programmable processors, and the sensors and other hardware that interface with them, enable automation and control of a multitude of operations. His expertise with these devices is being applied to an upgrade of our 1/6 scale pilot model controls. We are increasing the automation of the valving on our power system to take advantage of the vacuum or pressure remaining in the power tube as the thrust carriage passes by the blower stations. Sensors along the power tube will report position and velocity of the thrust carriage, as well as residual vacuum in the tube to a programmable controller which will actuate individual valves to optimize efficiency. Luke brings a fresh perspective and a keen intellect to our team, if only for the summer. In addition to his work on the train controls, he has also been helping with the design, construction, and installation of an improved control and monitoring system for our small private water district. It is a pleasure for all of us here at Flight Rail to work with Luke. We will certainly miss him when he leaves this fall!