Auto-calibration of load cell in measuring discrete weights
AssigneeJohnson Health Tech Co., Ltd.
InventorsRobert C. Burck, Mark J. Kannel
Life of this patent
Estimating the term…
Abstract
A method to automatically calibrate a load cell without the need to remove the loading on the load cell. This method takes advantage of the fact that weight stack strength equipment uses generally known discrete weight increments, and any signal drift in the load cell can be automatically recalibrated by offsetting the load cell signal to accurately reflect the expected discrete weight increments without the need for unloading the load cell and without the need for a manual recalibration of the load cells.
Claims11
A method of operating a load measurement system of a strength machine having plates, one or more of which are moved during an exercise, the plates having expected mass values that are representative of the mass values of the plates, the method comprising:
- measuring a load of plates being moved;
- comparing the measured load to the expected mass values;
- and
- determining an estimated mass of the weights being moved, the estimated mass corresponding to one of the expected mass values.
A method of calibrating a load measurement system of a strength machine having a plurality of plates, one or more of which are moved during an exercise, each of the plurality of plates having expected mass values that are representative of the mass values of the plates, the method comprising:
- measuring a first load of a first number of plates being moved;
- comparing the first measured load to the expected mass values in order to arrive at a first estimated mass corresponding to one of the expected mass values;
- calculating a first remainder as a difference between the first estimated mass and the first measured load;
- measuring a second load of a second number of plates being moved;
- comparing the second measured load to the expected mass values in order to arrive at a second estimated mass corresponding to another one of the expected mass values;
- calculating a second remainder as a difference between the second estimated mass and the second measured load;
- calculating an offset for a force calculation of the load measurement system based on the first remainder and the second remainder;
- and
- applying the calculated offset to future measuring steps.
A method of calibrating a load measurement system of a strength machine having a plurality of plates, one or more of which are moved during an exercise, each of the plurality of plates having expected mass values that are representative of the mass values of the plates, the method comprising:
- measuring a first load of a first number of plates being moved;
- comparing the first measured load to the expected mass values in order to arrive at a first estimated mass corresponding to one of the expected mass values;
- calculating a first remainder as a difference between the first estimated mass and the first measured load;
- measuring a second load of a second number of plates being moved;
- comparing the second measured load to the expected mass values in order to arrive at a second estimated mass corresponding to another one of the expected mass values;
- calculating a second remainder as a difference between the second estimated mass and the second measured load;
- calculating a gain for a force calculation of the load measurement system based on the first remainder and the second remainder;
- and
- applying the gain to future measuring steps.
Dependencies are inferred from the claim text.