Accelerometer-based shock/vibration testing apparatus and associated methods for a portable computer

For use in conjunction with a computer having first and second power supply structures with outputs from which electrical power may be transmitted respectively during operational and non-operational periods of the computer, a method of determining the shock and vibration loading to which the computer is subjected during such operational and non-operational periods, said method comprising the steps of:

• positioning an accelerometer and first and second memory means in the computer;
• electrically powering said accelerometer using the first power supply structure, and enabling said accelerometer to transmit sensed shock/vibration load data to said first memory means for storage therein, in response to transmission of electrical power from said output of said first power supply structure;
• and
• electrically powering said accelerometer using the second power supply structure, and enabling said accelerometer to transmit sensed shock/vibration load data to said second memory means for storage therein, in response to cessation of transmission of electrical power from said output of said first power supply structure.

Computer apparatus comprising:

• a computer having disposed therein a circuit board, an AC-to-DC power board with an output from which electrical power may be generated during operational periods of the computer, and a DC storage battery with an output from which electrical power may be generated during non-operational periods of the computer;
• an accelerometer mounted on said circuit board and operative to sense shock and vibration loads to which said computer is subjected during said operational and non-operational periods thereof, said accelerometer having an electrical power supply input and an electrical measurement signal output;
• first and second memory chips mounted on said circuit board and operative to receive and store shock and vibration load data for subsequent retrieval;
• and
• switchover circuitry operative to automatically:
• (1) couple said power supply board output to said accelerometer electrical power supply input, and to couple said accelerometer electrical measurement signal output to said first memory chip, during said operational periods of said computer, and
• (2) couple said DC storage battery output to said accelerometer electrical power supply input, and to couple said accelerometer electrical measurement signal output to said second memory chip, during said non-operational periods of said computer, said switchover circuitry including:
• a first two-position electrical switching relay powered by said power supply board and operatively interconnecting said accelerometer electrical measurement signal output and said first and second memory chips, and
• a second two-position electrical switching relay powered by said power supply board and operatively interconnecting said accelerometer power supply input, said power supply board, and said DC storage battery.