Airdropped mine’s water-entry acceleration measurement technology based on variant time interval data storage

Impact acceleration is a vital parameter to an airdropped mine system design, it has strong relation to its mechanical parts’ action. Airdropped mine’s drop, parachute release, and water-entry will generate slow and fast acceleration signals. Overrun of data memory will occur with a constant frequency sample. Traditional data compression methods can not be used in a tiny storage test and a measurement system due to its limited volume and power supply. A variant time interval of data storage algorithm which could be fit into a low power CPLD chip was introduced. The algorithm analyzed data’s change from a ADC at high speed sampling, and changed the time interval of data storage automatically. It reduced the data storage capacity but kept enough information for both slow and fast acceleration signals. An airdropped mine’s acceleration built-in measurement system based on this proposed algorithm had been built. Test results showed that it worked well and could be used for other dynamic measurement applications.