| 摘要 |
An automatic parachute opening device provides the possibility of opening main and reserve parachutes at predetermined heights above the ground. A microcontroller within the device monitors the rate of descent and height above ground level as derived from barometric pressure readings and actuates the main canopy if the rate of descent is above a predetermined level at a predetermined height above the ground. If the speed is also above this predetermined level at a second, lower, height above the ground, the reserve parachute is deployed. A clock 44 and a pressure transducer 42 provide signals to a microcontroller 41 which controls the pin puller solenoid 36 of the main parachute container (57,fig.1) and the connector 40 of the cord-cutter guillotine (62) of the reserve parachute container (59). Microcontroller 41 may calculate five heights: (1) activation lock-out height below which, in ascent, there is no activation signal; (2),(3) reserve and main "wake-up" heights below which, in ascent, there is no activation signal for the reserve and main parachutes, respectively; and (4),(5) reserve and main activation heights. The reserve heights are lower than the main heights. |
