A system for positioning equipment comprises a hoist including an electric motor coupled to a pulley for exerting a pulling force upon a tension member that extends to a distal end configured to attach to an elevated structure. The system also comprises a portable power supply including a battery supplying DC power, and an inverter configured to generate and supply AC power to the hoist for driving the electric motor and thereby lifting the hoist toward the elevated structure. A method for pre-positioning a hoist comprises attaching a tension member of a hoist to an elevated structure; generating AC power from a DC source by an inverter of a portable power supply; and lifting the hoist using the portable power supply. Thus, the hoist can be pre-positioned in an elevated location before utility power is available.

A zero-gravity hoist system including a chain fall, a motor coupled to the chain fall and configured to drive the chain fall in one or more directions, a power supply configured to provide power to the motor, and a controller having one or more electronic processors. The one or more electronic processors are configured to measure a first force of a load in response to receiving an input, store the measured first force in a memory of the controller, measure a second force of the load, determine a difference between the second measured force and the first measured force, and adjust a height of the load based on determining that the second force differs from the first force by a predetermined threshold.

A simulated environment includes a motion control system. The motion control system comprises a suspension structure, a housing slidably engaged to the suspension structure such that the suspension controller translates in a planar manner relative to the suspension structure. A rotary component is rotatably attached to the housing. A plurality of winches are attached to the rotary component, the plurality of winches having cables to allow longitudinal movement of the cables parallel to a force of gravity.

A simulated environment includes a motion control system. The motion control system comprises a suspension structure, a housing slidably engaged to the suspension structure such that the suspension controller translates in a planar manner relative to the suspension structure. A rotary component is rotatably attached to the housing. A plurality of winches are attached to the rotary component, the plurality of winches having cables to allow longitudinal movement of the cables parallel to a force of gravity.

A method and system to prevent unexpected operation of a motor when the voltage level on a DC bus drops is disclosed. The voltage level on the DC bus is monitored during a run command. When a run is commanded, the processor executes a control routine to determine a desired amplitude and frequency for the output voltage required to control the motor connected to the motor drive. If the desired frequency of the output voltage exceeds a maximum frequency for the measured voltage on the DC bus, as established by parameters stored in the motor drive, the motor drive limits the output frequency to the maximum frequency for the corresponding measured voltage. The motor drive continually monitors the measured voltage present on the DC bus and further reduces the maximum output frequency allowed during the run if the present value of the measured voltage drops below a previously measured value.

The present invention relates to a lifting device for example in the form of a crane such as a tower crane, with a hoisting gear comprising a hoisting cable which runs off from a drum that can be driven by a hoisting gear drive, and a hoisting gear brake for holding the hoisting cable in a braked position. The invention furthermore relates to a method for starting up the hoisting gear of such a lifting device from the braked position in which the hoisting gear brake holds a hoisting load, wherein a starting torque is built up by a hoisting gear drive against the closed hoisting gear brake, and the hoisting gear brake is released upon or after reaching the starting torque. According to the invention it is proposed that when the hoisting gear brake is closed, the current hoisting load is detected by means of a load detection device and the starting torque is adjusted by the hoisting gear controller with reference to the detected current hoisting load such that the hoisting force provided by the starting torque of the hoisting gear corresponds to the detected, current hoisting load.

A remote controller includes a shell having an upper shell and a lower shell, and further includes a light emitting module and a fixing plate for fixing the light emitting module. The fixing plate is fixedly connected to an inner side of the lower shell. The light emitting module is fixedly connected to one side, far away from the lower shell, of the fixing plate. The fixing plate is provided with a first light-transmitting hole for displaying the light emitting module; and the lower shell is provided with a second light-transmitting hole for displaying the fixing plate.

A remote controller includes a shell having an upper shell and a lower shell, and further includes a light emitting module and a fixing plate for fixing the light emitting module. The fixing plate is fixedly connected to an inner side of the lower shell. The light emitting module is fixedly connected to one side, far away from the lower shell, of the fixing plate. The fixing plate is provided with a first light-transmitting hole for displaying the light emitting module; and the lower shell is provided with a second light-transmitting hole for displaying the fixing plate.

Systems are provided for fairleads, including a frame. The frame includes a first opening and a second opening. The first opening extends through the frame from a front-facing surface of the frame to a rear-facing surface of the frame. The second opening extends through the frame from the front-facing surface of the frame to the rear-facing surface of the frame. A cable extends through the first opening.

Systems are provided for fairleads, including a frame. The frame includes a first opening and a second opening. The first opening extends through the frame from a front-facing surface of the frame to a rear-facing surface of the frame. The second opening extends through the frame from the front-facing surface of the frame to the rear-facing surface of the frame. A cable extends through the first opening.