Force measurement system and a method of calibrating the same

A force measurement system, comprising:

• a force measurement assembly configured to receive a load, the force measurement assembly including:
• a surface for receiving the load, the surface comprises a plurality of different load regions;
• and
• at least one force transducer, the at least one force transducer configured to sense one or more measured quantities and output one or more signals that are representative of the load being applied to the surface of the force measurement assembly;
• a data processing device operatively coupled to the force measurement assembly, the data processing device configured to receive the one or more signals that are representative of the load being applied to the surface of the force measurement assembly, the data processing device further configured to reference a stored global calibration matrix for the force measurement assembly, and to determine a location of the applied load on the surface of the force measurement assembly from the one or more signals of the at least one force transducer using the stored global calibration matrix, the data processing device additionally configured to reference stored calibration data for a plurality of calibration points disposed proximate to the location of the applied load, and to compute a local calibration matrix using the stored calibration data for the plurality of calibration points, the data processing device further configured to compute one or more refined local output forces or moments of the applied load using the local calibration matrix.

A method of calibrating a force measurement system, the method comprising the steps of:

• providing a force measurement assembly configured to receive a load, the force measurement assembly including:
• a surface for receiving the load, the surface comprising a plurality of different load regions;
• and
• at least one force transducer, the at least one force transducer configured to sense one or more measured quantities and output one or more signals that are representative of the load being applied to the surface of the force measurement assembly;
• providing a data processing device operatively coupled to the force measurement assembly, the data processing device configured to receive the one or more signals that are representative of the load being applied to the surface of the force measurement assembly;
• selecting a plurality of points on the surface of the force measurement assembly for applying one or more known loads;
• applying the one or more known loads at the plurality of points on the surface of the force measurement assembly, and storing raw load data for the plurality of points on the surface of the force measurement assembly using the data processing device;
• generating, by using the data processing device, a global calibration matrix for the force measurement assembly using the stored raw load data for the plurality of points on the surface of the force measurement assembly, and storing the global calibration matrix in non-volatile memory;
• and
• generating, by using the data processing device, local calibration matrices for the plurality of different load regions on the surface of the surface of the force measurement assembly, and storing the local calibration matrices in non-volatile memory.