US 5,325,028 A · System and method for magnetic tape leader block extraction

Abstract

A system and method for controlling an amount of force supplied by a motor to move an object from an at-rest position is presented. The system comprises a motor controller configured to provide a motor control signal to control the amount of force supplied by the motor, and a position sensor configured to detect an actual position of the object being moved by the motor and to send an actual position signal to the motor controller. The motor control signal supplied by the motor controller controls the motor such that the motor supplies a cubic increase in force on the object to move the object from its at-rest position. The motor controller comprises a profile generator, configured to provide an acceleration profile, a velocity profile and a position profile, and to output a drive signal in response to the position profile, wherein the position profile represents a desired position of the object as a function of time. The position profile is a cubic profile as a function of time. The motor controller further comprises a summer to generate an error signal based on the difference between the desired position and the actual position. The motor controller also includes a compensator to generate the motor control signal in response to the error signal.

Claims17

Dependent claims

A system for controlling an amount of force supplied by a motor to move an object form an at-rest position, comprising:

a motor controller having an input configured to accept an actual position signal indicating an actual position of the object and an output configured to provide a motor control signal to control the amount of force (F) supplied by the motor;
and
a position sensor, coupled to said motor controller, configured to detect said actual position of the object being moved by the motor as a function of time (t) and to send said actual position signal to said motor controller;
wherein said motor control signal supplied by said motor controller controls the motor such that the force (F) supplied by the motor on the object to move the object from its at-rest position at a rate that is proportional to t.sup.N, where N is greater than 2.

1 more element

A magnetic tape drive, having a threading mechanism, the threading mechanism configured to thread a magnetic tape having a leader block along a transport path, comprising:

a thread arm, configured to grasp the leader block and extract the leader block from a tape cartridge and to transport the leader block along the transport path;
a thread motor, connected to said thread arm, configured to provide a force to said thread arm, wherein said force is used to extract said leader block;
a motor controller, coupled to said thread motor, configured to provide a motor control signal to control said force supplied by said thread motor;
and
a position sensor, coupled to said motor controller, configured to detect an actual position of said thread arm along the transport path as a function of time (t) and to send said actual position signal to said motor controller;
wherein said motor control signal supplied by said motor controller controls the motor, such that the force supplied by the motor to move the object from its at-rest position is proportional to t.sup.N, where N is greater than 2.

3 more elements

Dependencies are inferred from the claim text.

System and method for magnetic tape leader block extraction

Life of this patent

System and method for magnetic tape leader block extraction

Life of this patent

Abstract

Claims17