Control system for movable storage units

Abstract

A movable storage system includes at least two movable storage units, a brush-less motor accommodated in each of the units for moving the units in movement directions, each of the motors comprising a plurality of stators and a rotor, and each of the motors including a sensor. Each sensor detects an angular position and a rotational speed of a respective rotor of each motor using the magnetic poles of the rotor. Each sensor outputs an angular position signal representing the angular position and a rotational speed signal representing the rotational speed of the rotor. A motor control is associated and in communication with each motor and sensor, which is operable for controlling the motor. The controls are adapted to receive the position and speed signals of each sensor with each control having a signal-outputting terminal to provide a command signal output to its respective motor. In addition, the system includes a master control that is in communication with the motor controls, which obtains the speed and angular position signals from each of the motor controls. Further, each unit includes a communications board, which allows exchange of information between the motor controls and the master control, which includes the speed and angular position signals, wherein the master control commands a respective unit that needs to be moved to move or stop in a movement direction by sending a control signal to the motor control of the respective unit. The motor control compares the speed and the position signals with the control signal to provide a motor control signal to the motor of the respective unit to control electric current supplied to the stators of the motor of the respective unit to control rotational speed and angular position of the rotor of that motor.

1 . A movable storage system comprising: 
 at least two movable storage units being movable in at least two movement directions;    a brush-less motor accommodated in each of said movable storage units for moving said units in the movement directions, each of said brush-less motors comprising a plurality of stators and a rotor, said rotor having magnetic poles;    each of said brush-less motors including a sensor, each of said sensors detecting an angular position and a rotational speed of a respective rotor using said magnetic poles of said respective rotor, each of said sensors outputting an angular position signal representing the angular position and a rotational speed signal representing the rotational speed of said respective rotor;    a brush-less motor control associated and in communication with each respective brush-less motor of said brush-less motors and said sensor of said respective brush-less motor, said motor controls operable for controlling said brush-less motors, said motor controls adapted to receive said position signals and said speed signals of each respective sensor of said brush-less motors, each of said motor controls having a signal-outputting terminal to provide a command signal output to said respective brush-less motor;    a master control in communication with said brush-less motor controls, said master control obtaining said speed signal and said angular position signal from each of said brush-less motor controls;    each of said movable storage units including a communications board, said board allowing exchange of information between said brush-less motor controls and said master control, said information including said speed signals and said angular position signals; and    wherein said master control commands a respective movable storage unit that needs to be moved to move or stop in said movement direction by sending a control signal to said brush-less motor control of said respective movable storage unit, said brush-less motor control comparing said speed signal and said position signal with said control signal to provide a motor control signal to said motor of said respective movable storage unit to control electric current supplied to said stators of said motor of said respective movable storage unit to control rotational speed and angular position of said rotor of said motor of said respective movable storage unit in the movement direction.    
   
   
       2 . The movable storage system of  claim 1 , wherein said sensors are Hall-effect sensors, said Hall-effect sensors producing said position and speed signals.  
   
   
       3 . The movable storage system as defined in  claim 2 , wherein said position signals and said speed signals generated by said Hall effect sensors are processed into a set of pulses input to said motor controls, said motor controls controlling electric current supplied to said stators on said motors to control speed and position of said rotors.  
   
   
       4 . The movable storage system of  claim 3  further comprising a sweep control module providing an infrared photo eye, said photo eye detecting objects in an aisle of the movable storage system, said sweep control module configured to prevent said movable storage units from running into an object in the aisle; and 
 wherein said sweep control module sends an aisle object detection signal to said master control, said master control sending a stop or start signal to a motor control of an appropriate movable storage unit.    
   
   
       5 . The movable storage system of  claim 3  further comprising: 
 a light carpet system providing an infrared beam to scan a floor of said movable storage system;    said infrared beam scans the floor of the movable storage system and detects the presence of an object on the floor of the movable storage system;    wherein said light carpet system sends a floor object detection signal to said master control when an object is detected; and    said master control sending a stop or start signal to at least one of said motor controls when a floor object detection signal is received.    
   
   
       6 . The movable storage system of  claim 5  further comprising: 
 an input/output module connected to said motor control; and    wherein said input/output module controls an identification address of said motor control.    
   
   
       7 . The movable storage system of  claim 6 , wherein one of said master control and said motor control controls operation of said motors according to a command from an input/output module.  
   
   
       8 . The movable storage system of  claim 7 , wherein said communications board allows communication between said motor control and said sensor.  
   
   
       9 . The movable storage system of  claim 8 , wherein one of said master control and said motor control provides directional commands of rotate clockwise or rotate counterclockwise for said motors to change direction of movement for each storage unit.  
   
   
       10 . The movable storage system of  claim 9 , wherein one of said master control and said motor control provides speed variation signals to said brush-less motors.  
   
   
       11 . The movable storage system of  claim 10  further comprising a master display showing status of said motor controls.  
   
   
       12 . The movable storage system of  claim 11  further comprising a master display showing status of said motors.  
   
   
       13 . The movable storage system of  claim 12  further comprising a master display showing status of said sensors.  
   
   
       14 . The movable storage system of  claim 1 , wherein said communications boards are integrated into said motor controls.  
   
   
       15 . A movable storage system comprising: 
 at least two movable storage units being movable in at least two movement directions;    a motor associated with and selectively moving each of said movable storage units for moving said units in the movement directions, each of said motors comprising a rotor and a sensor for detecting the angular position and rotational speed of the rotor; and    a control system in communication with said sensors, said control system controlling the linear position of said movable storage units based on said angular position and rotational speed of the rotors.    
   
   
       16 . The movable storage system according to  claim 15 , wherein said motors comprise brush-less motors.  
   
   
       17 . The movable storage system according to  claim 16 , wherein each of said brush-less motors includes a sensor, a rotor with a plurality of magnetic poles, and a plurality of stators each including an electromagnet, each of said sensors detecting an angular position and a rotational speed of a respective rotor using said magnetic poles of said respective rotor, each of said sensors outputting an angular position signal representing the angular position and a rotational speed signal representing the rotational speed of said respective rotor to said control system.  
   
   
       18 . The movable storage system according to  claim 16 , wherein said control system includes a master control and a carriage control for each motor, said master control in communication with each of said carriage controls.  
   
   
       19 . The movable storage system according to  claim 18 , wherein said carriage controls receives said angular position signals and said rotational speed signals from said sensors.  
   
   
       20 . The movable storage system according to  claim 18 , wherein said carriage controls communicate at least the content of said angular position signals and said rotational speed signals to said master control, and when an open aisle request is received by said master control, said master control determines which respective movable storage units need to be moved, the direction in which said respective movable storage units need to moved, and the left or right distance the respective movable storage units need to be moved, and said master control generating a command signal to each carriage control of the respective movable units that need to be moved.  
   
   
       21 . A method for controlling for a movable storage unit in a movable storage system having at least two movable storage units being movable in at least two movement directions, a motor with a rotor, a sensor accommodated in each of the motors, a control system in communication with the sensors and for selectively powering the motors, the method comprising the steps of: 
 detecting the rotational position of the rotor of the motor of the respective unit by a sensor;    sending rotor position data to the control system;    surveying the status of the units with the control system based on the rotor position data;    receiving an aisle open request from an input request source;    determining which unit to move and in what direction to fulfill the aisle open request based on the rotor position data;    determining the amount or rotation needed for the rotor of the respective motor to fulfill the aisle open request; and    sending a drive signal to the motor of the respective unit to rotate the rotor the amount needed to fulfill the open aisle request.    
   
   
       22 . The method according to  claim 21 , further comprising: 
 providing a brush-less motor with stators, a rotor, and a sensor in each of the movable storage unit,    sensing the angular position and rotational speed of the rotor of each motor with their respective sensors; and    communicating the angular position and rotational speed signals to the control system.    
   
   
       23 . The method of  claim 22  further comprising: 
 checking an aisle of the system for an object with a sweep control module; and    stopping operation of a motor of an associated storage unit when an object is detected in the path of the associated storage unit by the sweep control module.    
   
   
       24 . The method of  claim 23  further comprising: 
 checking a floor of the system for an object with a light carpet module; and    stopping operation of a motor of an associated storage unit when an object is detected in the path of the associate storage unit by the light carpet module.