Abstract: Magnetic levitation methods and apparatus use arrays of vehicle magnets to provide three forces: suspension, guidance and propulsion. The magnets, which can be permanent magnets or superconducting magnets operating in the persistent current mode, have associated control coils that allow the magnets to provide a controllable attractive force to a laminated steel rail. The control coils adjust the gap between the magnets and the rails so as to be in stable equilibrium without requiring significant power dissipation in the control coils. These same magnets and steel rails also provide lateral guidance to keep the vehicle on the track and steer the vehicle on turns. The suspension control coils can provide lateral damping by means of offset magnets in the suspension arrays. Windings in transverse slots in the steel rails are excited with currents that react against the field produced by the vehicle magnets to create vehicle propulsion.

Abstract: Synchronous motors according to the invention operate at higher efficiency, with lower cost, reduced mass and reduced cogging. Magnet dimensions are selected that reduce cogging forces to a negligible amount even though there are fewer slots than normal. Optionally, it is possible to use non-overlapping windings with deeper and open slots. The approach is applicable to both rotary and linear motors and motors using either permanent magnets or electromagnets in the field structure. It is particularly relevant to linear or rotary motors that have a large air gap, and to small motors that must deliver a high ratio of thrust or torque to motor mass.

Abstract: A pathway-based method, apparatus and system for tracking, sensing and communicating with an object, such as a carriage or vehicle moving on a pathway. The system includes a transmitter winding along the pathway that is energized by a transmitter and one or more sensing windings in which a signal is induced. The vehicle contains a transducer that creates a position-indicating coupling of the transmitted signal into the sensing windings. The transducer may be a passive ferromagnetic or conductive body that locally alters coupling between the windings, or a tuned coil carried on the vehicle that couples energy received from the transmitter into a sensing winding. Absolute position may be established at regular intervals using a discrete position sensor, such as a Hall Effect magnetic field sensor, and, the signal derived from the sensing windings can be monitored, by counting cycles or determining phase, to determine a precise vehicle position.

Abstract: A module for a linear motor propulsion guideway contains a combination of linear motor propulsion, vehicle guidance, position sensing, communication, and vehicle or pallet running surface subcomponents. These are integrated during the manufacturing into a single component or module for ease of shipping and precision of installation at a site where the guideway is to be installed. A single manufacturing operation is used to position, affix, and encapsulate the selected subcomponent(s) in a module or modules. For example, the component(s) can be designed to be located in a plastic injection mold, typically, a reaction injection mold (RIM), which allows the subcomponent(s) to be positioned, aligned, and encapsulated in a single manufacturing step that has only a several minute cycle time. In this manner positional accuracy among the relationship of the subcomponent(s) can be maintained within a small tolerance (on the order of 0.25 mm) while costs remain very low.

Abstract: Inductive transfer methods and structures combine, in a single system, at least two of the three functions of transferring power, communicating data, and sensing position with a vehicle on a guideway. A set of conductors is installed on the guideway to inductively couple a multiplicity of diverse signals with a corresponding set of conductors on the vehicle. The vehicle may be moving or stationary, and signals may be coupled in one or both directions. Coupling is effected without direct electrical contact, through a common region or gap, and the structures provide suitable and precise air gap control for the conductors effecting coupling of each signal. In addition, the windings are arranged with a topology and/or symmetry to cancel crosstalk between different signals.

Abstract: A system for guidance and/or switching of a vehicle or other object comprises a guideway, a guide plate that moves along the guideway, and a magnetic field source that induces a magnetic force between the guide plate and at least a portion of the guideway over which the guide plate is moving. The guide plate is attached to the vehicle or coupled to its steering systems. The magnetic force centers the guide plate along the guideway by opposing any lateral deviation from center. The magnetic field source is a permanent magnet, an electromagnet (including a superconducting magnet) or any other known magnetic field source. It is preferably included in, or forms part of, the guide plate. Likewise, the guide rail preferably comprises ferromagnetic or paramagnetic material, i.e., a material that forms a temporary magnet in the presence of the magnetic field of the source.

Abstract: The invention provides guideway-based methods, apparatus and systems for tracking, sensing and communicating with objects, such as track and roadway vehicles, as well as waystations therefore. Such a system comprises a winding, a transmitter and a receiver. The winding is made up of two or more phased conductors connected to form one or more closed current paths. The phased conductors are conductive elements (such as wires) shaped or configured in periodically repeating patterns, such as saw tooths, sinusoids or square waves. The transmitter applies to at least one of the phased conductors a position-sensing signal which has an envelope that varies as a periodic function of a first position along (or relative to) the winding. The sensor, which is disposed at a second position along the winding, detects the position-sensing signals on the winding and generates a signal indicating the distance between the first and second positions.