Texas Instruments Corporation

Raytheon Company

Martin Austin Wand

Thomas J Doty

John P Williston

Haradon J Rice

David F Summerville

Phen-Lan Huang

Jesse Gregory Villarreal, Jr

Sreenivas Kothandaraman

Frank J Moizio

John F Brady

Yale P Vinson

David D Ratcliff

James C Debruin

Edward C Musall

Chuan-Fu Lin

Robert R Bless

Michael Andrew Hannah

Michael Weinstein

Steve T Jenkins

Paul Bastian Fernandez

Kenneth Rachels

Anh V Ho

A digital system is provided that converts compressed data using an indexed transcoding lookup table. A stream of compressed data samples has data samples that represent one of n values corresponding to the first compression format. The transcoding table has at least n indexed entries, and each of the n indexed entries contains a data value corresponding to a second compression format. The transcoding table is accessed by using each of a portion of the received data samples as an index into the table to form a set of transcoded data samples that have a second compression format. The set of transcoded data samples form a stream of compressed data samples that have the second compression format. The transcoding table may be augmented to perform transcoding error correction by concatenating an error value with the data sample to index the table.

Error correcting DPCM transcoding

A method to record high frame rate video, compatible with existing industry standards, that permits selecting either slow-motion playback or true speed playback with synchronized audio.

System and method for recording high frame rate video, replaying slow-motion and replaying normal speed with audio-video synchronization

This invention describes a reconfigured form of the PID compensator such that the rate of change of the position error is inherently limited without affecting the performance of the servo loop when the position error is small. The technique described here maintains the performance of the conventional PID compensator when the position error is close to zero, which is the operating point of primary interest.

Servo loop PID compensator with embedded rate limit

A hybrid stabilization system for isolating a pointing vector of a gimbal from the motion of a vehicle base is provided. The hybrid stabilization control system includes a rate feedback loop generating a rate feedback compensation value in response to a measured rate difference between a pointing vector rate of motion and a vehicle base rate of motion, a rate feedforward loop generating a rate feedforward compensation value in response to a measured inertial vehicle base rate of motion, a position feedback loop generating a position feedback compensation value in response to a measured position difference between a pointing vector angular position and a vehicle base angular position, a position feedforward loop generating a position feedforward compensation value in response to a measured inertial vehicle base angular position. A controller receives a pointing vector position command and generates a gimbal control signal in response to the rate feedback compensation value, rate feedforward compensation value, position feedback compensation value, and position feedforward compensation value.

Gimbal pointing vector stabilization control system and method

A method and system for digital resolution translation. An input frequency is received, as is a desired output frequency. The desired output frequency is measured directly and compared with the input frequency. The specified output frequency is dynamically adjusted to compensate for variations in the input frequency, while a fixed relationship between the input and output is kept intact. The relationship between the input and output frequencies can be arbitrary, non-integer or integer. The system consists of an execution process ( ) and the adjusted output frequency is sent to a system as a sampling signal. The system reset/restart capability allows for a repeatable phase relationship between the output and the input from any given reset point.

Digital resolution translator

A method for measuring the temperature of a scene using a detector having at least one reference pixel, with an integratable sampling circuit associated with each pixel. Initially, an ambient reference temperature is observed with the reference pixel(s) to provide a parameter, generally voltage, indicative of that temperature to provide a constant voltage output indicating that temperature by varying the sampling circuit integration time. Each non-reference pixel is exposed to different scene and ambient temperatures and the integration time for each set of data for each pixel is recorded. For each pixel, an equation is provided relating integration time to pixel voltage when the ambient temperature and the scene temperature are the same to correct for offsets and an equation is provided relating integration time and offset corrected pixel value to the difference between the ambient temperature and the scene temperature when the ambient temperature and scene temperature differ for correction of responsivity. An equation is provided relating integration time to ambient temperature for calculating ambient temperature. The voltage level for each of the pixels and the integration is determined, the offset correction for each pixel is calculated based upon the integration time and the offset correction is applied to the pixel value for each pixel. The responsivity corrected value is calculated for each pixel based upon the integration time and the offset corrected pixel value. The ambient temperature is calculated based upon the integration time and the temperature difference between the ambient temperature and the scene temperature for each pixel which is calculated based upon the responsivity corrected pixel value using a scale factor determined during calibration. The ambient temperature and the difference between the ambient and the scene temperatures are added to obtain the actual scene temperature.

Ambient temperature micro-bolometer control, calibration, and operation

The invention is a modular and hierarchically organized set of computer programs which comprise methods for controlling a system of semi-autonomous automatically guided vehicles, such as mobile robots. The methods include control programs which: execute in stationary control computers; communicate between the stationary control computer programs and corresponding programs which execute in mobile control computers aboard the vehicles; operate independently in mobile control computers aboard the vehicles. The invention allows the system executive program to command the mobile vehicles to start, to stop, to transfer material to or from the vehicles, to change batteries in the vehicles, to park the vehicles at specific points in a factory, to move the vehicles from point to point in a factory, and to remove the vehicles from the factory. The invention improves the performance of conventional automatically guided vehicle systems by maximizing the autonomy of individual vehicles while retaining sufficient supervisory control at the system executive level to provide the maximum flexibility in routing and scheduling the activity of the vehicles. The invention 'closes the loop' in an automatically guided vehicle system by providing the highest level of control between mobile vehicles and stationary control computers.

Hierarchical control system for automatically guided vehicles

The invention is a method of static collision avoidance for multiple automatically guided vehicles (AGVs) on bidirectional paths. It defines the allowable travel path for an AGV as a series of path segments through or between possible destination points (called nodes) which are defined for the factory floor. AGVs can move to or through any of these nodes and can arrive in a predetermined order, according to 'rules' defined by the method. The invention provides better performance than conventional AGV systems by allowing multiple AGVs to coexist in the same pathways without collision or excessive queueing in systems which use free-roving AGVs having programmable bidirectional paths. This new ability maximizes the degrees of freedom of AGV movement while minimizing collisions and 'deadlock.'

Static collision avoidance method for multiple automatically guided

The invention provides a method for communicating the need to move a mobile robot, such as an AGV, from one location (node) to another, on a node-by-node basis, incrementally, among the nodes established in a physical environment such as a factory. The invention also provides the means to generate the commands necessary to accomplish this motion, by providing specific steering and drive information such as angle and speed to the mobile robot or AGV. The invention accomplishes these tasks in response to direct commands from a stationary controller as well as in response to continuous node-by-node position updates provided by an external navigation system, such as a visual navigation system, or an internal dead-reckoning navigation system, or both.

Method for controlling the movements of a mobile robot in a multiple

A visual navigation system provides absolute position information to multiple automatically guided vehicles (AGVs) such as mobile robots. The beacon-equipped AGVs emit light visible to overhead television cameras. The beacons are arranged and controlled so that the vision systems can acquire, measure, and report the locations of multiple AGVs. The system controller incorporates a programmable 'factory map', or knowledge base, of allowable paths of travel for the AGVs, which navigate by dead reckoning with periodic position updates from the visual navigation system. The visual navigation system notifies the autonomous AGVs and the system controller when an AGV strays from its command path. The combination of computer controls in the elements of the system provides the means to stop and to recover straying AGVs. The navigation system visually monitors normal AGV travel, off-course corrections, 'lost' AGV searches, and recovery. Thus, it provides closed-loop, servo-like operation.

Closed-loop navigation system for mobile robots

The invention is a method of dynamic collision avoidance for multiple automatically guided vehicles (AGVs) on bidirectional paths. It calculates windows, or areas of computer memory, against which it matches the reported positions of AGVs. The invention acts on information from a central data base in which the factory or operating space of the AGVs is mapped and from AGV position updates supplied by an independently operating visual navigation system. The invention dynamically calculates the locations and dimensions of the windows for each position update. Since these position updates occur in real time, many times each second, the invention provides the means for the AGV system's controller to prevent collisions between the AGVs and other objects without minimizing the degrees of freedom of AGV movement.

System for dynamically determining position of multiple automatically

A mobile vehicle controller for controlling a mobile apparatus that travels along a commanded path. The mobile vehicle controller has a dead reckoning navigation procedure for navigating the controllable mobile apparatus along the commanded path in response to positions data. The mobile apparatus determines its position and provides the position data. A vision system provides the absolute position to the mobile apparatus. The dead reckoning position data is periodically modifying with the absolute position. The dead reckoning procedure is synchronized with the vision system.

Mobile vehicle controller utilization of delayed absolute position data

A controllable mobile apparatus travels along a commanded path under the control under a navigation system that provides speed and direction commands to navigate the controllable mobile apparatus. The controllable mobile apparatus has a plurality of wheels which are driven by servo control systems in response to speed commands that are provided by the navigation system. The trajectory of the mobile apparatus is also controlled by the navigation system, and it includes a servo system that is, in the illustrated embodiment, the same as the servo system used for controlling the speed of the mobile apparatus. Additionally, there is implemented a software filter system which filters the speed and direction commands.

Software servo velocity filter with bounded output

A synchronous decode circuit for an incremental encoder is disclosed which comprises analog-to-digital converters for converting in phase and quadrature encoder signals to transistor-to-transistor logic (TTL) compatible signals, a latch for receiving current logic level signals and the previous logic level signals for a gray code, a programmable read only memory (PROM) for decoding the logic level signals and generating clock and direction enable signals, and gating logic connected to the PROM for gating clock and direction signals to counters of the system, the counters are connected to a latch under control of the computer to latch the count of movement in preselected directions for the computer. In another embodiment the PROM includes scaling jumper means or error detection means or both for, respectively, adjusting the range of measurement (scale factor) and indicating error in the logic level signals.

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Plano, TX, United States of America

Martin Austin Wand