Motion capture system that combines sensors with different measurement ranges

摘要

Motion capture system with a motion capture element that uses two or more sensors to measure a single physical quantity, for example to obtain both wide measurement range and high measurement precision. For example, a system may combine a low-range, high precision accelerometer having a range of −24 g to +24 g with a high-range accelerometer having a range of −400 g to +400 g. Data from the multiple sensors is transmitted to a computer that combines the individual sensor estimates into a single estimate for the physical quantity. Various methods may be used to combine individual estimates into a combined estimate, including for example weighting individual estimates by the inverse of the measurement variance of each sensor. Data may be extrapolated beyond the measurement range of a low-range sensor, using polynomial curves for example, and combined with data from a high-range sensor to form a combined estimate.

主权项

1. A motion capture system that combines sensors with different measurement ranges comprising
a motion capture element comprising
a memory;a plurality of sensors comprising at least two sensors that each measure the same physical quantity, wherein said physical quantity is equal to or is a function of one or more of a position, an orientation, a velocity, an acceleration, an angular velocity, or an angular acceleration of said motion capture element;a first communication interface;a microprocessor coupled with said memory, said plurality of sensors, and said first communication interface, wherein said microprocessor is configured to
collect sensor data from said plurality of sensors, wherein said sensor data comprises a sensor value from each sensor of said plurality of sensors;store said sensor data in said memory;transmit said sensor data to a computer via said first communication interface;wherein
each sensor of said at least two sensors has a measurement range comprising a closed interval between a lower measurable value and an upper measurable value, said measurement range having an interior comprising a set of measurable values that are strictly greater than said lower measurable value and strictly less than said upper measurable value;said measurement range associated with each sensor of said at least two sensors differs from the measurement range associated with at least one other sensor of said at least two sensors; wherein said computer is configured to
receive said sensor data;calculate an individual sensor estimate of said physical quantity from said sensor value associated with each sensor of said at least two sensors;combine the individual sensor estimate across said at least two sensors to form a combined estimate of said physical quantity;analyze a motion of said motion capture element based on said sensor data and on said combined estimate of said physical quantity.