Rapistan Systems Advertising Corp.

Dematic Gmbh

Doane, Martin R.

Zeitler, David W.

David W Zeitler

Clyde Miin-Arng Ko

Andrew R Black

Frank W Veit

Rhonda J Verploegen

Charles W Bozarth

Martin R Doane

Douglas L Milliman

Garry A Koff

Matt Werner

A method and apparatus for controlling gaps between articles traveling on a conveyor system includes providing a plurality of tandem conveying surfaces defining a series of sequentially arranged conveying surface interfaces. At least one of the conveying surfaces associated with each of said conveying surface interfaces is an adjustable-speed conveying surface. At least one article sensor is provided adjacent at least one of the conveying surface interfaces. The article sensor provides information on positions of the articles. The speeds of the tandem conveying surfaces are controlled in a manner that establishes controlled gaps between articles, by identifying a controllable gap that can be adjusted between articles at a particular conveying surface interface and adjusting the controllable gap at the particular conveying surface interface. The control adjusts the controllable gap by adjusting the speed of the adjustable speed conveying surface associated with the particular conveying surface interface using a feedback controller. Gaps between articles are sequentially adjusted at the series of sequentially arranged conveying surface interfaces.

Conveyor induct system

A control architecture for material handling includes multiple tiers of controllers, such as three. The lowest-level controllers interact directly with sensors and actuators used in the material handling system, such as photo-eyes and motors used with conveyors. The lowest-level controllers receive higher level commands from one or more mid-level controllers. The mid-level controllers, in turn, receive still higher level commands and information from at least one upper level controller. Each mid and low level controller is designed to include sufficient intelligence to deal with many of the signals and messages it receives without having to forward those signals or messages to the next higher level controller and await instructions from that higher level controller. The system thus distributes intelligence amongst the controllers. The system is well-adapted for application to conveyor control systems.

Tiered control architecture for material handling

An induction subsystem for a conveyor sortation system and method of inducting articles includes providing a plurality of tandem conveying surfaces. The speeds of the conveying surfaces are individually controllable. At least one sensor is provided for sensing articles on at least one of the conveying surfaces. A control is responsive to the at least one sensor for controlling the speeds of said conveying surfaces in a manner that controls relative positions of articles. The control defines a plurality of feedback-gapping algorithms. Each of the feedback-gapping algorithms is defined between adjacent conveying surfaces for adjusting relative speeds of those adjacent conveying surfaces as a function of at least one parameter of the articles. The control controls relative positions of articles with the feedback-gapping algorithms beginning with a pair of adjacent conveying surfaces and cascading through adjacent pairs of adjacent conveying surfaces.

Conveyor induction subsystem and method of inducting articles using feedback-gappers

A conveyor system, such as an induction subsystem for supplying articles to a sortation subsystem, and method of conveying articles includes providing a conveying surface for conveying a series of articles and at least one sensor for sensing the articles on the conveying surface. A control is provided which establishes at least one parameter for each of the articles and controls the conveying surface as a function of the at least one parameter of each of the articles. The control includes a computer and a program for the computer. The program includes at least one probability estimator. The control determines the at least one parameter of each of the articles at least in part by the at least one probability estimator. The control controls gaps between articles or synchronizes arrival of articles at the sortation system.

Conveyor induct system with probability estimator

A positive displacement sorter apparatus and method includes providing a plurality of slats being interconnected in an endless web, an upper run of the web defining a conveying surface, and a plurality of pusher shoes gliding along at least some of the slats to laterally displace articles on the conveying surface. A linear motor system is provided to propel the web and includes a plurality of linear motor secondaries at the slats and at least one primary for propelling the secondaries. A control system controls the primaries.

Positive displacement shoe and slat sorter apparatus and method

A material handling system uses high-frequency location devices for determining the location of mobile units, such as AGVs, overhead mono-rails, conveyor components, or individual articles being transported by such units. The high-frequency location devices may also be used to identify the contents and/or routing information for material being moved within a facility. AGVs may incorporate the high-frequency location devices into their navigation systems to utilize the position and/or heading updates provided by the location devices in guiding the vehicle. The location devices work in cooperation with a number of stationary location devices, such as beacons, that are positioned within the environment at known locations, such as in or adjacent the ceiling of the workplace environment. High-frequency radars may also be used to provide electronic bumpers to the AGVs, allowing them to sense obstacles and take appropriate action to avoid collisions with the obstacles.

Material handling systems with high frequency radio location devices

A method and apparatus for controlling the steering of an automatic guided vehicle (AGV) includes simultaneously correcting the vehicle's heading and position errors. The vehicle may include first and second steering control loops that determine the vehicle's position and heading errors, respectively. Separate commands are generated from these control loops to steer the vehicle in a manner that tends to reduce these errors. The vehicle may include a forward and a rearward pair of wheels. For correcting position errors, the first control loop issues the same steering command to both the forward and rearward pair of wheels. For correcting heading errors, the second control loop issues a steering command to the rearward pair of wheels that is summed together with the first control loop's steering command prior to being applied to the rearward pair of wheels.

AGV position and heading controller

A conveyor induct system includes a control point subsystem for measuring the point at which control of an article transitions from one conveyor to another. The induct system also includes a subsystem for accurately creating or controlling the gaps between articles on the conveyor system. The control point subsystem monitors the location, and changes in the speed, of an article as it passes between two conveyors operating at different speeds. The gap control subsystem provides real time monitoring and measuring of the package gaps. The measured package gaps are fed into a feedback control system which alters the speed of a conveyor in order to change the gapping as desired.

Conveyor induction system

An automated guided vehicle system and method includes providing at least one automated-guided vehicle (AGV) and a pathway for the AGV. A sensor assembly on the AGV senses magnet assemblies on the pathway as the AGV is transported over that magnet assembly. A navigation and guidance system determines the location of the maximum magnitude of the magnetic field by mathematically fitting a curve to the magnitude of portions of the magnetic field sensed by said magnetic sensors and determines a maximum value of the curve. At least some of the said magnet assemblies each produce a bipolar magnetic field extending generally transverse to the pathway and the sensor assembly produces an output indicative of magnitude and polarity of respective portions of the bipolar magnetic field. The navigation and guidance system determines a location of maximum magnitude of the opposite polarities of the bipolar magnetic field and a correction factor. The correction factor corrects for offset of the maximum magnitudes of the field from a predetermined location on that magnet assembly including correcting for any skew of the bipolar magnetic field with respect to said pathway.

Growing community of inventors

Caledonia, MI, United States of America

David W Zeitler