Trip recorder

Claim 1

A vehicle monitoring, recording and analyzing system comprising: (a) a plurality of sensors located within said vehicle for the purpose of sensing operating parameters therefrom, said sensors generating data signals representing varying magnitudes corresponding to values of said operating parameters; (b) a data processing and recording device located entirely on-board said vehicle and comprising: (i) computing means, including a central processing unit (CPU) and a real time clock device, for periodically sampling each of said data signals in sequence and producing data samples representative of the magnitudes of said data signals from each of said sensors; (ii) program memory storage means for storing an operating program for said CPU; (iii) data memory storage means for receiving and storing said data samples; (iv) program data memory storage means for storing program control parameters to control said operating program for said CPU; (v) data compression means for implementing a data compression scheme operating in accordance with said operating program to store compressed data in a block of successively arranged memory locations in said data memory storage means and comprising: (a) means for mathematically accumulating the said data samples from any one of said sensors for fixed time intervals for determining sums of the said data samples in each fixed time interval; (b) means for storing consecutive sums in consecutive memory locations in said block of said data memory storage means; (c) means for detecting occurrences of sums of zero in each of a predetermined number of consecutive fixed time intervals, said means for detecting said occurrences, upon detection of each occurrence, causing said means for storing to cease storing said consecutive sums and also forming summary blocks in said block in said data memory storage means; (d) means for recording in each summary block the total length of time during which said consecutive sums remain zero; (e) means for detecting reoccurrences of sums greater than zero, said means for detecting said reoccurrences causing said means for recording to cease recording said summary blocks, and said means for storing to resume storing said consecutive sums; (vi) power supply means associated with said vehicle for operating said CPU, said program memory storage means, said real time clock device and said data memory storage means; (vii) power supply means independent of said vehicle for operating said real time clock device and said data memory storage means in the absence of power from said power supply means associated with said vehicle; (viii) data communication means operative to read said compressed data from said data memory storage means and to transfer said compressed data to external data processing equipment.

Claim 9

A system as defined in any one of claims 1 or 7 and further including power failure detection means to ensure proper shutdown in the event of a power failure or removal of the system from the vehicle, and further storing in said data memory storage means information as to the time and duration of said power failure or removal.