Machine logic airtime sensor for board sports
An airtime sensor for board sports includes a detector for generating signals representative of vibration associated with motion of a board sports vehicle along a surface. State machine logic filters the signals through a first low pass filter, filters the signals through a second low pass filter, and combines filtered signals from the first and second low pass filters to determine airtime.
1. An airtime sensor for board sports, comprising:
a detector for generating signals representative of vibration associated with motion of a board sports vehicle along a surface; and
state machine logic for (a) filtering the signals through a first low pass filter, (b) filtering the signals through a second low pass filter; and (c) combining filtered signals from the first and second low pass filters to determine airtime of the board sports vehicle off of the surface.
2. Airtime sensor of claim 1 , the detector comprising an accelerometer for sensing the vibration.
3. Airtime sensor of claim 2 , the state machine logic limiting the signals, after the step of rectifying and before the step of filtering.
4. Airtime sensor of claim 2 , the state machine logic rescaling the signals, after the step of rectifying and before the step of filtering.
5. Airtime sensor of claim 1 , the detector comprising a microphone for sensing the vibration.
6. Airtime sensor of claim 1 , the detector comprising a piezoelectric element for sensing the vibration.
7. Airtime sensor of claim 1 , wherein filtering the signals through the first low pass filter comprises filtering the signals through about a 1-pole 20 Hz low pass filter.
8. Airtime sensor of claim 1 , wherein filtering the signals through the second low pass filter comprises filtering the signals through about a 1-pole 2 Hz low pass filter.
9. Airtime sensor of claim 1 , the state machine logic differentiating the signals prior to the steps of filtering.
10. Airtime sensor of claim 1 , the state machine logic rectifying the signals prior to the step of filtering.
11. Airtime sensor of claim 1 , the state machine logic limiting the signals prior to the step of filtering.
12. Airtime sensor of claim 1 , the state machine logic differentiating and rectifying the signals prior to the step of filtering.
13. Airtime sensor of claim 1 , the state machine logic generating a first power signal after the step of filtering through the first low pass filter and generating a second power signal after the step of filtering through the second low pass filter.
14. Airtime sensor of claim 13 , the state machine logic comparing the first power signal against two preselected values to identify possible takeoffs and landings.
15. Airtime sensor of claim 13 , the state machine logic comparing the second power signal against three preselected values to identify possible takeoffs and landings.
16. Airtime sensor of claim 1 , the state machine logic determining motion as a prerequisite to determining airtime.
17. Airtime sensor of claim 1 , the state machine logic comparing potential takeoffs, correlated to comparisons of filtered signals through the first low pass filter, to confirmed takeoffs, correlated to comparisons of filtered signals through the second low pass filter.
18. Airtime sensor of claim 1 , the state machine logic comparing potential landings, correlated to one or more comparisons of filtered signals through the first low pass filter, to confirmed landings, correlated to one or more comparisons of filtered signals through the second low pass filter.