Controlling head seeking speed in disk storage units by limiting displacement of head with respect to its supporting headarm

In a method of operating a disk storage system including the steps:

• mounting a transducer on a fine actuator, mounting the fine actuator on a carriage movably mounted with respect to a record member having elongated tracks for cross-track movements and wherein said fine actuator can accelerate and decelerate faster than said carriage, establishing a reference position for the transducer on the carriage, sensing for displacements of said transducer from said reference position, actuating the carriage to follow movements of the transducer for maintaining said transducer at said reference position;
• moving the transducer from a current track toward a target track across other tracks between the current and target tracks at a maximal acceleration and then at a predetermined deceleration of said fine actuator for effecting a predetermined maximum cross-track speed of the transducer and actuating the carriage to follow the cross-track movements of the fine actuator;
• sensing and indicating the cross-track speed of the transducer;
• sensing and indicating the displacement of the transducer from said reference position;
• providing a predetermined cross-track speed of said transducer crossing said other tracks and a predetermined maximum desired displacement of the fine actuator from said reference position;
• and
• detecting the sensed and indicated cross-track speed exceeding said predetermined cross-track speed and detecting the indicated displacement of the transducer from said reference position exceeding said predetermined desired maximum displacement and limiting the cross-track speed of the transducer to not exceed said predetermined cross-track speed nor said maximum displacement.