Abstract: Systems and methods for controlling an output of a light fixture. A light fixture of one construction includes four or more light sources and is configured to produce an output that mimics the color temperature changes of an ideal black-body radiator based on one or more input parameters. The input parameters correspond to, for example, a desired target color and an intensity for the desired target color. A white point setting is determined based on the one or more input parameters and a relationship between the one or more input parameters and the color temperature of an ideal black-body radiator. A color temperature transform is selected based on the white point color temperature setting, and is used to determine a color coordinate corresponding to a modified target color. A set of light source output values corresponding to the modified target color are identified, and the light sources are driven to the identified output values.

Abstract: A lift assembly comprising a plurality of elongate members (e.g., cables) positioned for movement in a longitudinal direction, a drive mechanism (e.g., a drum) coupled to move the elongate members in the longitudinal direction, and a loft block including a sheave located to redirect at least one of the elongate members to a non-parallel path that is not parallel to the longitudinal direction, wherein a remainder of the elongate members travel along a parallel path that is above the sheave. The loft block can include an idler bar having an upper surface that is higher than an upper surface of the sheave. For example, the idler bar can be positioned directly above the sheave.

Abstract: A performance venue having a dynamic load management system for use in managing loads. The system uses a dead man circuit as a means for determining the actual or anticipated dynamic load produced by moving loads, and then disables the system by opening the dead man circuit when too many loads are moved or selected to be moved. Preferably, the invention is embodied in a dead man circuit is pure hardware, and is free of software components. The invention also provides a method of controlling movement of loads in a performance venue having a plurality machines. In its basic form, the method comprises selecting at least one of the machines for movement, closing a dead man circuit, and opening the dead man circuit if the current in the dead man circuit falls outside a predetermined range.

Abstract: A lift assembly system and method can include a substantially rectangular tube, a motor operably connected to first and second traction drives and a rotatable drum and structurally connected to one end of the tube, a head block fixed to the opposite end of the tube, and a plurality of loft blocks positionable at an infinite number of locations within the tube. An elongate member attached on one end to the drum can be routed through a generally horizontal path from the drum to the first and second traction drives, the head block, and the loft blocks, and then through a generally vertical path from the loft block to an attached article. The elongate member can be wound about the drum to raise the article, and unwound from the drum to lower the article. The system can further include a load-side braking mechanism. The tube can include a compressible material adapted to absorb at least a portion of a horizontal load placed on the lift system.

Abstract: A lift assembly system and method can include a substantially rectangular tube, a motor operably connected to first and second traction drives and a rotatable drum and structurally connected to one end of the tube, a head block fixed to the opposite end of the tube, and a plurality of loft blocks positionable at an infinite number of locations within the tube. An elongate member attached on one end to the drum can be routed through a generally horizontal path from the drum to the first and second traction drives, the head block, and the loft blocks, and then through a generally vertical path from the loft block to an attached article. The elongate member can be wound about the drum to raise the article, and unwound from the drum to lower the article. The system can further include a load-side braking mechanism. The tube can include a compressible material adapted to absorb at least a portion of a horizontal load placed on the lift system.

Abstract: A segmented touch screen overlies the display or displays of a console having an operating system and display controller for the display. A touch screen controller is continuously connected to each of the touch screen segments and separate touch position information is obtained for each touch screen segment. The console operating system can be supplied with separate position information for each segment or with a single touch position for combined segments. A number of docking module ports near the display optionally receive docking modules that cover segments of the touch screen and display. A module, including tactile elements such as push button switches, can be docked at any port. When a module is detected, the touch screen segment under the module is disabled and the display under the module is switched to display module specific information.

Abstract: A lift assembly system and method can include a substantially rectangular tube, a motor operably connected to first and second traction drives and a rotatable drum and structurally connected to one end of the tube, a head block fixed to the opposite end of the tube, and a plurality of loft blocks positionable at an infinite number of locations within the tube. An elongate member attached on one end to the drum can be routed through a generally horizontal path from the drum to the first and second traction drives, the head block, and the loft blocks, and then through a generally vertical path from the loft block to an attached article. The elongate member can be wound about the drum to raise the article, and unwound from the drum to lower the article. The system can further include a load-side braking mechanism. The tube can include a compressible material adapted to absorb at least a portion of a horizontal load placed on the lift system.

Abstract: Systems and methods for controlling the output of a plurality of light sources. The system can include four or more light sources (e.g. light emitting diodes (“LEDs”)) and a controller. The light sources are included in, for example, a luminaire. The respective outputs of the plurality of light sources are controlled using a hue and purity (“HP”) control technique. The HP technique includes selecting a dominant hue (e.g., green, blue, red, etc.). The purity of the selected hue is then modified to include or remove wavelengths of light adjacent to the selected hue. For example, if the selected hue is green, gradually reducing the purity of the selected hue gradually increases the presence of cyan and amber in the output of the luminaire. As the purity is reduced further, additional wavelengths of light are included, but the output of the luminaire remains, in essence, green.

Abstract: A current sensing transformer having a low impedance primary winding is connected in series with a filter and load circuit supplied with output current by a high frequency switching PWM power supply such as a sinewave dimmer. Sensed output current is supplied to a microprocessor based programmable controller. The controller performs a routine including a family of overcurrent tests. Tests of the family are satisfied by the presence of different output current values for different time durations. At least one of the tests is enabled only at low requested output voltages or dimming levels. In response to satisfaction of any of the tests, a series power switching stage of the power supply is rendered nonconductive to shut down the power supply.

Abstract: Current sensing resistors are connected directly to output terminals of MOSFETs forming the series switching stage of a PWM sinewave dimmer. An analog sensed current signal is coupled through an EMI resistant current link to comparators that provide an overcurrent indication in response to an overcurrent condition. A logic circuit overrides PWM control signals from a programmable controller, and operates drivers to render the series switching stage nonconductive and to render a clamp switching stage conductive until after the end of the current PWM duty cycle power on segment. The logic circuit sends an overcurrent signal through an optocoupler to an input of the programmable controller. The input of the controller is polled at a clock frequency for overcurrent signals and if the count exceeds a limit in any half cycle, or a maximum sum in sixteen half cycles of the AC supply, the series switching stage is rendered nonconductive and the clamp switching stage is rendered conductive pending a reset signal.

Abstract: The solid state switching section of a high frequency PWM switching power supply may encounter problems in accurately regulating output power when the requested output power is above a threshold level, the threshold level typically being a high level approaching one hundred percent of the power of the sinusoidal AC power source. Below the threshold level, the power supply is operated in a full PWM mode to regulate the output power level. Above the threshold level, the power supply is operated in a full on, continuously conducting mode in a central part of the half cycles of the AC supply. Outside of this central portion, the power supply is operated in the in the PWM mode, using a duty cycle within the capability of the solid state switching section. The output power level is regulated by varying the duration of the central full on portion of the half cycle. A similar control method is used for reducing heat generated by the solid state switching section of the power supply.

Abstract: A floor marking system includes a floor having a predetermined location intended for use of a predetermined character, the predetermined location being marked with impinging light. The floor marking system also includes a lighting unit having a light source for marking light onto the floor at a predetermined location. A patterning device is disposed between the light source and the floor, and is configured and arranged to mark at least one of a graphic pattern and a color onto the floor at the predetermined location with the impinging light. The at least one of the graphic pattern and the color marked on the floor by the lighting unit and the patterning device forms an indicator, and the indicator corresponds to the character of use of the floor at the predetermined location.

Abstract: A segmented touch screen overlies the display or displays of a console having an operating system and display controller for the display. A touch screen controller is continuously connected to each of the touch screen segments and separate touch position information is obtained for each touch screen segment. The console operating system can be supplied with separate position information for each segment or with a single touch position for combined segments. A number of docking module ports near the display optionally receive docking modules that cover segments of the touch screen and display. A module, including tactile elements such as push button switches, can be docked at any port. When a module is detected, the touch screen segment under the module is disabled and the display under the module is switched to display module specific information.

Abstract: A current sensing transformer having a low impedance primary winding is connected in series with a filter and load circuit supplied with output current by a high frequency switching PWM power supply such as a sinewave dimmer. Sensed output current is supplied to a microprocessor based programmable controller. The controller performs a routine including a family of overcurrent tests. Tests of the family are satisfied by the presence of different output current values for different time durations. At least one of the tests is enabled only at low requested output voltages or dimming levels. In response to satisfaction of any of the tests, a series power switching stage of the power supply is rendered nonconductive to shut down the power supply.

Abstract: The solid state switching section of a high frequency PWM switching power supply may encounter problems in accurately regulating output power when the requested output power is above a threshold level, the threshold level typically being a high level approaching one hundred percent of the power of the sinusoidal AC power source. Below the threshold level, the power supply is operated in a full PWM mode to regulate the output power level. Above the threshold level, the power supply is operated in a full on, continuously conducting mode in a central part of the half cycles of the AC supply. Outside of this central portion, the power supply is operated in the in the PWM mode, using a duty cycle within the capability of the solid state switching section. The output power level is regulated by varying the duration of the central full on portion of the half cycle. A similar control method is used for reducing heat generated by the solid state switching section of the power supply.

Abstract: A floor marking system includes a floor having a predetermined location intended for use of a predetermined character, the predetermined location being marked with impinging light. The floor marking system also includes a lighting unit having a light source for marking light onto the floor at a predetermined location. A patterning device is disposed between the light source and the floor, and is configured and arranged to mark at least one of a graphic pattern and a color onto the floor at the predetermined location with the impinging light. The at least one of the graphic pattern and the color marked on the floor by the lighting unit and the patterning device forms an indicator, and the indicator corresponds to the character of use of the floor at the predetermined location.

Abstract: A shutter section includes a stack of circular plates independently rotatable in a nest formed as a laminar formation of rings. The plates have central openings defining a light path. Four central plates in the stack are shutter guide plates with radial guide slots slideably holding shutter blades. Two outer pairs of plates are shutter drive plates connected by cams to the shutter blades. Simultaneous rotation of a shutter guide plate and associated shutter drive plate causes rotation of an associated shutter blade around the light path. Rotation of a shutter drive plate while the associated shutter guide plate is stationary causes the cam to move the associated shutter blade radially. The nest is enclosed by end plates. A motor section has motors driving pinions to rotate the circular plates. The circular plates, rings pinions and shutter blades are made of sheet metal. Shutters may be provided as interleaved pairs each driven by a pair of rotatable drive plates.

Abstract: An input line filter separates an ac sinusoidal power source from a power switching stage having a series switching section and a clamp switching section. Both the series switching section and a clamp switching section include complementary pairs of high power and high speed MOSFETs. The series switching section is connected in series between the input line filter and the inductor of an output load filter between the power switching stage and a load. The clamp switching section is connected to shunt the inductor and load. Synchronous operation is achieved by alternately operating the series and clamp switching sections to conductive conditions at a high pulse width modulation frequency. The duty cycle is selected to provide a sinusoidal output waveform with a desired amplitude. A microprocessor based programmable controller provides control signals for alternate conduction of the series and clamp switching sections.

Abstract: A zoom lens system includes a motor driven lens assembly that is movable on a track in a normal movement range for adjusting the light beam range angle of a luminaire. A pair or doors are pivoted to opposite sides of the frame of the lens assembly and are normally biased to an inactive position where the doors are parallel to and outside of the light path in the luminaire. The doors hold optical media such as diffuser gels. The lens assembly can be moved beyond the normal movement range to an actuation position where projections on the doors engage actuation abutments adjacent the track to move the doors to an active position overlying the lens with the optical media in the light path. A latch holds the door in the active position. The lens assembly can be moved beyond the actuation position to a deactivation position where a deactivation abutment releases the latch freeing the doors to return to the inactive positions.