Abstract:
An apparatus includes a head transducer configured to interact with a magnetic recording medium and a heater configured to thermally actuate the head transducer. A thermal sensor at or near the head transducer is configured to produce a sensor signal. Circuitry is coupled to the heater and configured to cause an oscillation in heater power. The heater power oscillation causes an oscillation in the sensor signal. A detector is coupled to the thermal sensor and configured to detect head-medium contact using the oscillating sensor signal and heater power.
Abstract:
An apparatus comprises a heat-assisted magnetic recording (HAMR) head, a sensor, and a controller. The HAMR head is configured to interact with a magnetic storage medium. The sensor is configured to produce a signal indicating the occurrence of head-medium contact. The controller is configured to receive the signal and concurrently determine from the signal if the occurrence of head-medium contact is caused by a first contact detection parameter, a second contact detection parameter, or both the first and second contact detection parameters.
Abstract:
A method of detecting a contact between a transducing head and a storage medium is provided. The method applies an input signal, having a select power level and known frequency, to an actuator for actuating the head. An output signal is obtained in response to the input signal. At least one signal component is extracted from the output signal at the same or a harmonic of the same known frequency as the input signal applied to the actuator. Whether the at least one extracted signal component indicates a contact between the head and the medium is determined. The power level of the applied wave pattern is increased incrementally until the extracted signal component indicates a contact between the head and the storage medium.
Abstract:
Apparatus and associated method that contemplates performing a first atomic force microscope (AFM) scan of a first region of a sample centered at a first position at a first angle to produce a first scan image, the first AFM scan including a first component scan at a first speed and a second component scan at a second speed; performing a second AFM scan of the first region of the sample at a second angle to produce a second scan image, the second AFM scan including performing a third component scan at the first speed and a fourth component scan at the second speed; and correcting a first error in the first scan image based on the second scan image to produce a corrected image output.
Abstract:
An apparatus includes a head transducer configured to interact with a magnetic recording medium and a heater configured to thermally actuate the head transducer. A thermal sensor at or near the head transducer is configured to produce a sensor signal. Circuitry is coupled to the heater and configured to cause an oscillation in heater power. The heater power oscillation causes an oscillation in the sensor signal. A detector is coupled to the thermal sensor and configured to detect head-medium contact using the oscillating sensor signal and heater power.
Abstract:
In certain embodiments, a head-suspension assembly includes a resonator attached to either a head or gimbal. The resonator is configured to resonate at a predefined resonant frequency. In certain embodiments, disc drives includes a recording medium, a head-suspension assembly, and a resonator. The resonator is attached to either a head or gimbal of the head-suspension assembly. The resonator is configured to resonate at a predefined resonant frequency.
Abstract:
The application discloses a sensor device to measure friction force at a head-media interface. As disclosed, the sensor device has a transducer element oriented to provide an electrical output responsive to force or strain imparted to the transducer element along an in-plane axis. Sensor circuitry is coupled to the transducer element to process the electrical output to provide an output measure of friction force. In illustrated embodiments, the head includes an actuator element which is powered on/off at an on/off frequency to cyclically protrude a localized portion of the head. The on/off frequency of the actuator is used by the sensor circuitry to detect excitation of the sensor device due to friction force at the head-media interface.
Abstract:
An apparatus comprises a heat-assisted magnetic recording (HAMR) head, a sensor, and a controller. The HAMR head is configured to interact with a magnetic storage medium. The sensor is configured to produce a signal indicating the occurrence of head-medium contact. The controller is configured to receive the signal and concurrently determine from the signal if the occurrence of head-medium contact is caused by a first contact detection parameter, a second contact detection parameter, or both the first and second contact detection parameters.
Abstract:
The application discloses a sensor device to measure friction force at a head-media interface. As disclosed, the sensor device has a transducer element oriented to provide an electrical output responsive to force or strain imparted to the transducer element along an in-plane axis. Sensor circuitry is coupled to the transducer element to process the electrical output to provide an output measure of friction force. In illustrated embodiments, the head includes an actuator element which is powered on/off at an on/off frequency to cyclically protrude a localized portion of the head. The on/off frequency of the actuator is used by the sensor circuitry to detect excitation of the sensor device due to friction force at the head-media interface.
Abstract:
A method of detecting a contact between a transducing head and a storage medium is provided. The method applies an input signal, having a select power level and known frequency, to an actuator for actuating the head. An output signal is obtained in response to the input signal. At least one signal component is extracted from the output signal at the same or a harmonic of the same known frequency as the input signal applied to the actuator. Whether the at least one extracted signal component indicates a contact between the head and the medium is determined. The power level of the applied wave pattern is increased incrementally until the extracted signal component indicates a contact between the head and the storage medium.