It is really nice when you can count on a flow of ideas which make your systems better, lighter and lower cost! I admit that I find that flow most reliably connected with prayer, but I am thankful for the results. I will skip an update on my shrinking GLXP lander mass for today (but the 1.2 gram gearmotor actuators I am evaluating look very good, and my last post noted that it is hard to make a cold gas attitude jet “too small” for attitude control of a spacecraft in this mass range.) I am presently working on the “Reference” signal for my ElectroMagnetic Tractor Beam (EMTB). Since this also serves for 6 DOF relative position determination when a pair of spacecraft are maneuvered to create or sustain a desired formation, or for docking, it is necessary to create three “Orthogonal” signals which can be nicely separated from each other to generate the desired data. A set of three receiving coils (1, 2 and 3) are placed on one spacecraft and a set of three driven coils (A, B and C) on the other spacecraft. Comparing the A, B and C signals received by each of the receiving coils provides almost all the information necessary to determine the 6 DOF Relative Positions. One additional piece of information is needed to break a “Front Back” indeterminacy, but this is not difficult to obtain. The isolation of the three signals received by each coil is easiest if the signal voltages have “Temporal Orthogonality” (as do all the harmonics considered in the “Fourier Transform”). This can be accomplished if the signals are widely different frequencies, even if the “orthogonality” is not mathematically perfect. But since embedded computers (and some form of digital signal processing) will certainly be involved, the isolation is easier if the “Orthogonality” is directly imposed on the signal generators and reproduced in the digital filters. Last night I saw a very nice way to modify the circuits in my demonstration system to accomplish this, and make the coil preamps and analysis circuits simpler as well! Since the circuits are getting simpler, the mass and power of the assembly is shrinking as well.