Abstract: A method for desaturating reaction wheels of a spacecraft having a magnetic dipole is provided. The method includes orienting the spacecraft relative to an external magnetic field to apply a torque to the spacecraft via the magnetic dipole in a direction opposing momentum stored in the reaction wheels; and using the applied torque to unload at least some of the momentum stored in the reaction wheels. A corresponding spacecraft and non-transitory computer-readable medium are also provided.

Abstract: A method and system for creating a high spatial resolution image from a multidimensional imagery is disclosed. The technique exploits an intrinsic spatial distortion of the sensor that acquired the imagery and uses it as additional information to increase spatial resolution of the imagery. The method comprises obtaining a baseline image from the multidimensional imagery; deriving n×m?1 sub-pixel shifted images from the multidimensional imagery, where n and m are spatial resolution increase factors in x and y directions respectively, integers and greater than 1; organizing the baseline image and the n×m?1 sub-pixel shifted images from the multidimensional imagery; fusing the organized images using iterative back projection (IBP) to generate a high resolution image; and outputting the generated high resolution image.

Abstract: A technique for controlling drive currents to respective windings of a multi-winding brushless motor comprises monitoring an output of the motor and a demand of the motor, determining whether a failure mode has occurred, the failure mode being an instantaneous complete or partial failure to generate demanded output; and, upon detection of a failure mode on a first winding, distributing a demand contribution that is not being produced by the first winding to one or more of the windings that are not in a failure mode. The demand may be torque demand, and the failure modes may include winding failure, and voltage and/or current saturation. Improved torque output is generated by the redistribution of demand among phases in the event of a failure mode.

Abstract: A method and apparatus are provided for ripple suppression of brushless DC motors at any given velocity irrespective of the limited bandwidth of the driver/amplifier supplying the excitation currents to the stator. In a preferred embodiment, Fourier coefficients of the current waveform are calculated as a function of rotor velocity by taking into account the driver/amplifier's finite bandwidth dynamics. For a given velocity, Fourier coefficients of the series approximating the waveform (control signal) are calculated as a function of the rotor velocity and the amplifier dynamics, to generate a waveform that results in no torque or velocity pulsations. When changing the motor speed, the coefficients are updated (recalculated) based on the new desired velocity (and amplifier dynamics), resulting in generation of an updated waveform that results in no torque or velocity pulsations at the new motor speed.

Abstract: Control feedback for regulating strain output of a shape memory alloy (SMA) actuator using a stress sensor for outputting an indication of a mechanical resistance applied against the SMA actuator, and a state sensor for outputting an indication of a state of actuation of the SMA actuator has been found to be surprisingly accurate. Advantageously feedback detection can be provided with sensors that have low power requirements and can be controlled with simple electronics.

Abstract: A method and system for creating a high spatial resolution image from a multidimensional imagery is disclosed. The technique exploits an intrinsic spatial distortion of the sensor that acquired the imagery and uses it as additional information to increase spatial resolution of the imagery. The method comprises obtaining a baseline image from the multidimensional imagery; deriving n×m?1 sub-pixel shifted images from the multidimensional imagery, where n and m are spatial resolution increase factors in x and y directions respectively, integers and greater than 1; organizing the baseline image and the n×m?1 sub-pixel shifted images from the multidimensional imagery; fusing the organized images using iterative back projection (IBP) to generate a high resolution image; and outputting the generated high resolution image.

Abstract: Methods and systems for increasing the signal-to-noise ratio for satellite sensor data or signals, such as hyperspectral imageries (also referred to as datacubes due to their 3-dimensional nature). This is done by reducing the noise in the data or signals by first elevating the noise level temporarily for effective denoising. The denoising process is then performed in this condition and the noise level is then reversibly de-elevated after denoising. The denoising process comprises noise removal in both the spectral and the spatial domains. Once the denoising process is complete, the data is converted back from the spectral and spatial domains. Since this reconstruction process introduces errors, these errors are compensated for using the components from both the original data and denoised data filtered by the low pass filters.

Abstract: In order to determine positional information, about a mobile robot, Real Time Kinematic (RTK) Global Satellite Navigation System (GNSS) measurement data are obtained by at least two GNSS receivers mounted on the mobile robot. Estimates of the covariance matrices of the measurement data are computed. The RTK GNSS measurement data are combined according to the covariance matrices to obtain enhanced positional information. The results may be fused with data from an IMU to obtain driftless attitude and/or localization information.

Abstract: The present invention relates to a real-time wideband compressor for multi-dimensional data. The compressor comprises a plurality of compression engines for simultaneously compressing a plurality of data subsets of a set of input data vectors and providing compressed data thereof using one of SAMVQ or HSOCVQ data compression. Each compression engine comprises an along spectral vectors codevector trainer as well as an across spectral bands codevector trainer. The compression engines are programmable to perform either along spectral vectors codevector training or across spectral bands codevector training in combination with one of the SAMVQ or HSOCVQ techniques without changing hardware. The compressor further comprises a network switch for partitioning the set of input data vectors into the plurality of data subsets, for providing each of the plurality of data subsets to one of the plurality of compression engines, and for transmitting the compressed data.

Abstract: Methods and systems for compressing a continuous data flow for numerous applications where it is necessary to process large data sets such as hyper-spectral data cubes in real-time. A predetermined number of 2D focal plane frames in a boundary area of a previous regional data cube close to a current regional data cube are included in a training set used for codevector training for the current region. Therefore, no artificial boundary occurs between the two adjacent regions when codevectors trained in this way are used for codebook generation and encoding of the spectral vectors of the current regional data cube. This process substantially reduces image artifacts between adjacent regions. A remedy for the single bit error problem is also provided. Full redundancy of compressed data for a regional data cube is obtained by combining a previous regional data cube and the current regional data cube for codebook training.

Abstract: A system for replicating the behavior of a target robotic manipulator with respect to a payload and worksite, has a real-time simulator capturing the dynamics of the target robot manipulator; a mock-up of the payload and worksite; and an emulating robotic manipulator for interacting with said payload and worksite. The emulating robotic manipulator is controlled by the real-time simulator in a control loop to replicate the dynamical behavior of said target robotic manipulator in its environment by matching the impedance of the emulating robotic manipulator with that of the target robotic manipulator.

Abstract: The present invention relates to a method and system for compressing a continuous data flow in real-time based on lossy compression. In real-time data compression, a series of multi-dimensional data subsets acquired in a given period of time are treated as a regional data cube for the purpose of dividing a continuous series of data subsets into a plurality of data cubes. In a first embodiment implementation of parallel processing using a plurality of compression engines is facilitated by separating a data cube into a plurality of clusters comprising similar spectral vectors. By separating the data cube into clusters of similar spectral vectors no artificial spatial boundaries are introduced substantially improving image quality. Furthermore, the spectral vectors within a cluster are more easily compressed due to their similarity.

Abstract: A system and method for mental workload measurement and analysis are disclosed, which measure time intervals between saccades in eye movements. These intervals, called Inter Saccadic Intervals (ISI), characterize different levels of mental workload during operator performance, such as for MRO (Operator of Robot Manipulator). The device can include sensors for measuring oculometric potentials from the human face, an amplifier for amplifying measured potentials, an analog-to-digital (A/D) converter for generating digital output signals relating to the measured potentials, and a digital computer for continually measuring the electrooculogramic potential, extracting the saccades, calculating ISIS, and then determining quantitative criteria of mental workload based on the ISIS.

Abstract: A combined scheme of identification and torque control is provided for rotary hydraulic actuators. The composite controller consists of a dynamic feedback linearizing inner loop cascaded with a robust linear feedback outer loop. The proposed controller allows the actuator to generate desired torque irrespective of the actuator motion. In fact, the controller reduces significantly the impedance of the actuator as seen by its external load, making the system an ideal source of torque suitable for many robotics and automation applications. An identification method to extract the parameters of non-linear model of actuator dynamics and to estimate a bound for modeling uncertainty, used for synthesis of the outer optimal controller, is also presented. Results are illustrated experimentally on a pitch actuator of a Schilling industrial robot.

Abstract: For implementing an anthropomorphic visual telepresence system with high resolution and low loop latency a sequential color video loop is provided. A sequential color camera sequentially captures color images, each captured image consisting of a portion of a single color component, and provides information as separate color information relating to portions of the sequentially sensed color images. The information is transmitted as separate color information. A sequential color display receives the transmitted information and displays sequentially each color image within the received information. Synchronization means synchronize the sequence and color of corresponding portions of images comprising a single color in said display with the portions of the images sensed by said camera.

Abstract: A method and system for time-motion compensation for use with head mounted displays is disclosed. According to the method, a remote camera captures an image for display on a head-mounted display (HMD) including a viewing window. The image and camera position data is transmitted to a system including the HMD for display to a wearer of the HMD. The HMD position is determined. An offset between the HMD position and a known position of the HMD is determined as is an offset between the camera position and a known position of the camera. The image is offset relative to the viewing window of the image based on the difference between the two determined offsets.

Abstract: The present invention relates to a real-time wideband compressor for multi-dimensional data. The compressor comprises a plurality of compression engines for simultaneously compressing a plurality of data subsets of a set of input data vectors and providing compressed data thereof using one of SAMVQ or HSOCVQ data compression. Each compression engine comprises an along spectral vectors codevector trainer as well as an across spectral bands codevector trainer. The compression engines are programmable to perform either along spectral vectors codevector training or across spectral bands codevector training in combination with one of the SAMVQ or HSOCVQ techniques without changing hardware. The compressor further comprises a network switch for partitioning the set of input data vectors into the plurality of data subsets, for providing each of the plurality of data subsets to one of the plurality of compression engines, and for transmitting the compressed data.

Abstract: A system for replicating the behavior of a target robotic manipulator with respect to a payload and worksite, has a real-time simulator capturing the dynamics of the target robot manipulator; a mock-up of the payload and worksite; and an emulating robotic manipulator for interacting with said payload and worksite. The emulating robotic manipulator is controlled by the real-time simulator in a control loop to replicate the dynamical behavior of said target robotic manipulator in its environment by matching the impedance of the emulating robotic manipulator with that of the target robotic manipulator.

Abstract: A temperature- and evaporation-controlled device for the crystallization of proteins from a protein-containing solution. The device comprises a compartment, such as a microcapillary tube, for holding the solution from which crystals are formed. The compartment is in communication with a cold generating unit, such as a cold finger, that maintains a temperature lower than the temperature of the compartment thereby causing de-watering of the solution. A vacuum pump can be attached to the device to reduce vapor pressure to further promote de-watering of the solution. The device can be used terrestrially or in a microgravity environment, such as in outer space, for formation of high quality protein crystals.

Abstract: The present invention relates to a method for compressing a continuous data flow based on lossy compression. In real-time data compression, a series of data subsets acquired in a given period of time are treated as a regional data cube for the purpose of dividing a continuous series of data subsets into a plurality of data cubes. Reuse of existing codevectors is important in achieving high compression performance. For encoding spectral vectors on a subset-by-subset basis in a current region two types of codevectors are used, codevectors that have been newly trained for previous data subsets in the current region and codevectors trained for the previous region. The problem of a visible spatial boundary between two adjacent regions after decompression is overcome by reusing the codevectors trained from a previous region to encode the spectral vectors in the current region in order to attain a seamless conjunction of the two adjacent regions.