Abstract: A system for automatically trailering a marine vessel includes a set of coded tags coupled to a boat trailer, each storing data regarding its location on the trailer. A tag reader is located aboard the vessel, and estimates a first distance to a first coded tag in the set and a second distance to a second coded tag in the set. A position determination module uses the first and second estimated distances to determine position and heading of the vessel and the trailer in a given coordinate system. A feedback control module calculates a difference between the positions of the vessel and the trailer and a difference between the headings of the vessel and the trailer and determines vessel movements required to minimize the position and heading differences. A marine propulsion system automatically actuates a propulsion device to produce the required vessel movements to propel the vessel onto the trailer.

Abstract: A system for thermal cycling a sample utilizing electrolyte conductance heating. An electric current is passed through the sample to increase its temperature due to resistance heating. As the sample acquires more thermal energy its viscosity changes, which causes a change in resistance. Because of this characteristic, temperature of the sample can be measured as a function of resistance and temperature can be controlled using resistance of the solution as feedback to a circuit which controls the heating of the sample by electrical conductance.