Second generation NIST kibble balance and determining absolute mass

A process for determining absolute mass, the process comprising:

• providing a second generation NIST Kibble balance comprising:
• a main body and comprising a main body fulcrum node;
• a lever bar in mechanical communication with the main body and that pivots about the main body fulcrum node;
• a central flexural bridge in flexural mechanical communication with the main body and the lever bar;
• a measurement mass arm mechanically coupled to the main body via the lever bar, the central flexural bridge, and a mass arm flexural bridge;
• the mass arm flexural bridge in flexural mechanical communication with the measurement mass arm and the lever bar;
• a reference force arm mechanically coupled to the main body via the lever bar, the central flexural bridge, and a reference arm flexural bridge;
• and
• the reference arm flexural bridge in flexural mechanical communication with the reference force arm and the lever bar;
• discretely pivoting, by the electromagnet, the lever bar relative to the main body over a plurality of different displacements of the measurement mass arm;
• determining a capacitance gradient dC/dZ as a function of the different displacements of the measurement mass arm that occurs from discretely pivoting the lever bar relative to the main body;
• fixing a moving electrode of the actuator at a specific position determined by the displacement sensor;
• receiving the mass on the mass pan of the measurement mass arm;
• measuring a first change in voltage required by the actuator to maintain the specific position;
• removing the mass from the mass pan;
• measuring a second change in voltage required by the actuator to maintain the specific position;
• and
• calculating the absolute mass of the mass from the first change in voltage, the second change in voltage, and the capacitance gradient dC/dZ.

A process for determining absolute mass, the process comprising:

• providing a second generation NIST Kibble balance comprising:
• a main body and comprising a main body fulcrum node;
• a lever bar in mechanical communication with the main body and that pivots about the main body fulcrum node;
• a central flexural bridge in flexural mechanical communication with the main body and the lever bar;
• a measurement mass arm mechanically coupled to the main body via the lever bar, the central flexural bridge, and a mass arm flexural bridge;
• the mass arm flexural bridge in flexural mechanical communication with the measurement mass arm and the lever bar;
• a reference force arm mechanically coupled to the main body via the lever bar, the central flexural bridge, and a reference arm flexural bridge;
• and
• the reference arm flexural bridge in flexural mechanical communication with the reference force arm and the lever bar;
• oscillating, by the electromagnet, the lever bar relative to the main body to produce oscillatory linear displacements of the measurement mass arm;
• calibrating an electromagnet of the actuator as a function of the oscillatory linear displacements of the measurement mass arm;
• determining a BL product of the actuator after calibrating the electromagnet of the actuator;
• fixing the actuator at a specific position determined by the displacement sensor;
• receiving the mass on the mass pan of the measurement mass arm;
• measuring a first change in voltage required by the actuator to maintain the specific position;
• removing the mass from the mass pan;
• measuring a second change in voltage required by the actuator to maintain the specific position;
• and
• calculating the absolute mass of the mass from the first change in voltage, the second change in voltage, and the BL product.