초록 ▼

Improvements in accurately sensing a user manipulandum of a force feedback device. A force feedback device, coupled to a host computer, includes an actuator for outputting forces on a manipulandum and a sensor for detecting a position of the manipulandum. In one feature, a raw sensor value represent

Improvements in accurately sensing a user manipulandum of a force feedback device. A force feedback device, coupled to a host computer, includes an actuator for outputting forces on a manipulandum and a sensor for detecting a position of the manipulandum. In one feature, a raw sensor value representing manipulandum position is adjusted based on compliance between sensor and manipulandum, where the adjustment can be based on a compliance constant and an output force. In another feature, a range of motion of the manipulandum is dynamically calibrated from startup. One boundary value of an assigned initial range is set equal to a received sensor value if the sensor value is outside the initial range, and the other boundary value is adjusted to maintain the size of the initial range unless the other boundary value has already been sensed outside the initial range. In another feature, manipulandum position is accurately sensed by filtering raw sensor values for overshoot values occurring at limits to manipulandum motion and using the filtered value in the dynamic calibration. In another feature, sensing inaccuracies caused by compliance in the device are decreased by normalizing a raw sensor value to a normalized range of motion that includes a saturation zone at each end of the range that adjusts sensor values over a saturation level to the saturation level.

대표청구항 ▼

Improvements in accurately sensing a user manipulandum of a force feedback device. A force feedback device, coupled to a host computer, includes an actuator for outputting forces on a manipulandum and a sensor for detecting a position of the manipulandum. In one feature, a raw sensor value represent

Improvements in accurately sensing a user manipulandum of a force feedback device. A force feedback device, coupled to a host computer, includes an actuator for outputting forces on a manipulandum and a sensor for detecting a position of the manipulandum. In one feature, a raw sensor value representing manipulandum position is adjusted based on compliance between sensor and manipulandum, where the adjustment can be based on a compliance constant and an output force. In another feature, a range of motion of the manipulandum is dynamically calibrated from startup. One boundary value of an assigned initial range is set equal to a received sensor value if the sensor value is outside the initial range, and the other boundary value is adjusted to maintain the size of the initial range unless the other boundary value has already been sensed outside the initial range. In another feature, manipulandum position is accurately sensed by filtering raw sensor values for overshoot values occurring at limits to manipulandum motion and using the filtered value in the dynamic calibration. In another feature, sensing inaccuracies caused by compliance in the device are decreased by normalizing a raw sensor value to a normalized range of motion that includes a saturation zone at each end of the range that adjusts sensor values over a saturation level to the saturation level. er operable in a fourth mode in which the converter is operable in a chain of serially connected converters but the converter does not assert a ready signal when the end of conversion is received. 19. An analog to digital converter as claimed in claim 14, in which the third mode is a "chain, ready" mode in which the converter is connected in series with other converters and asserts an output when it and any preceding converters have completed their conversions irrespective of whether the converter is operable in a second mode. 20. An analog to digital converter as claimed in claim 1, in which the analog to digital converter further comprises a second input and a serial clock input, and wherein following the initiation of a conversion by applying a start of convert signal to the second input, the converter examines the status of its first input and the serial clock input, and if the first input is in the first predetermined state and the serial clock input is in a second predetermined serial clock state, then the analog to digital converter enters a fourth mode where it clocks data at the first input into a shift register for subsequent output and where the output does not assert a signal to indicate that a conversion is complete. 21. An analog to digital converter as claimed in claim 1, in which the analog to digital converter can be programmed by truncating a data read instruction cycle before all of the conversion result has been output. 22. An analog to digital converter as claimed in claim 1, wherein the first input is a serial data input and wherein the analog to digital converter further comprises a clock input and a convert input for initiating a conversion, and the analog to digital converter is programmable by inputting a control word via the serial data input. 23. An analog to digital converter comprising a converter section and an interface section, the interface section having a first input and an output for outputting the result of a conversion, and wherein in a first mode the output is asserted to a first predetermined state to indicate that the conversion has been completed when the conversion has been completed and the first input is at a first predetermined input state. 24. An analog to digital converter as claimed in claim 23, in which the converter further includes a clock input, and the conversion result is output in response to transitions of a clock signal at the clock input between a first and a second predetermined state. 25. An analog to digit