Bumpless crankshift position sensing

A method of determining crankshaft position of a running internal combustion engine comprising

• (a) providing a rotating member operationally coupled to said crankshaft such that the rotating member rotates two cycles per one engine cycle, said rotating member comprising a circumference which comprises a plurality of equidistantly spaced elements disposed thereon with at least one reference element;
• (b) positioning a first sensor proximate to said rotating member such that said first sensor produces a first series of signals corresponding to said plurality of equidistantly spaced elements and at least one reference element passing by said first sensor;
• (c) positioning a second sensor proximate to said rotating member such that said second sensor produces a second series of signals corresponding to said plurality of equidistantly spaced elements and said at least one reference element passing by said second sensor, wherein said second sensor is placed at a predetermined distance downstream of said first sensor with respect to the rotational direction of said rotating member;
• (d) modulating said second series of signals such that said second series of signals resembles said first series of signals thereby producing a modulated series of signals;
• and
• (e) generating a continuous stream of signals useful for determining crankshaft position, wherein said continuous stream of signals is based on
• (i) a combination of said first series of signals and said modulated series of signals if both of said first and second crank positioning sensors are operating,
• (ii) said first series of signals if said first crank positioning sensor is operating and said second crank positioning sensor is not operating, and
• (iii) said modulated series of signals if said second crank positioning sensor is operating and said first crank positioning sensor is not operating
• wherein continuous stream of signals is maintained, irrespective of a failure of either said first sensor or said second sensor, without needing to switchover from said first series of signals to said modulated series of signals, or vice versa.

A signal processor configured to receive respective signals from a first and second crank positioning sensor, said first and second crank positioning sensors offset from one another and arranged to sense the rotation of a rotating member comprising a plurality of elements thereon with at least one reference element, wherein said first crank positioning sensor and said second crank positioning sensor produce high signals corresponding passage of said elements, low signals corresponding to passage of the space between said elements, and a reference signal corresponding to said at least one reference element, said signal processor comprising

• a first processing module configured to process information from said first crank positioning sensor, thereby generating a processed first crank positioning signal series;
• and
• a second processing module configured to process information from said second crank angle sensor so as to create a reference signal corresponding to a reference signal from said first crank angle sensor;
• or, in place of a reference signal from said second crank angle sensor, creating an element signal corresponding to an element signal from said first crank positioning sensor, thereby generating a processed second crank angle signal series that resembles said processed first crank positioning signal series.

An engine control system for an internal combustion engine, wherein said engine comprises at least one cylinder, each cylinder retaining a piston, and wherein a crankshaft is operationally coupled to the pistons such that the crankshaft rotates twice per engine cycle and the position of each piston depends upon the rotational position of the crankshaft, said engine control system comprising:

• (a) a signal processor, wherein said signal processor is configured to receive signals from two or more crank positioning sensors;
• (b) a rotating member arranged to rotate in direct correlation with said crankshaft, said rotating member comprising a plurality of equidistantly spaced elements with at least one reference element;
• (c) a first sensor mounted proximate to said rotating member to sense the passage of said equally spaced elements, wherein said first sensor is communicatingly connected to said signal processor;
• (d) a second sensor mounted proximate to said rotating member to sense the passage of said equally spaced elements, wherein said second sensor is communicatingly connected to said signal processor;
• wherein said signal processor comprises a first processing module and a second processing module to receive and process said output signals from said first sensor and said output signals from said second sensor, respectively, said first and second processing modules configured to produce an active crank signal stream, said active crank signal stream persisting despite failure of either first sensor or second sensor, without needing to switchover receiving signals from one sensor to another.

A computer program product for use with a locomotive engine, said product comprising:

• a computer-usable medium comprising computer readable program code modules embodied in said computer-usable medium for manipulating signals from a first and second crank positioning sensors, said first and second crank positioning sensors generating a series of digital high signals, a series of digital low signals and at least one reference signal;
• computer readable first program code module for causing a computer to count the number of high signals occurring between two successive reference signals;
• computer-readable second program code module for causing said computer to convert at least one high signal from said first or second crank positioning sensors into a reference signal at a predetermined location on said series of high signals;
• computer-readable third program code module for causing said computer to create at least one high signal in place of said at least one reference signal from said first or second crank positioning sensors.

A computer program product for use with a locomotive engine, said product comprising:

• a computer-usable medium comprising computer readable program code modules embodied in said computer-usable medium for generating a continuous stream of signals useful for determining crankshaft position, said continuous stream of signals derived from a first series of signals from a first crank positioning sensor and a second series of signals from a second crank positioning sensor, said method comprising:
• a computer-readable first program code module for causing a computer to modulate said second series of signals to produce a modulated series of signals that resembles said first series of signals, thereby producing two series of signals that resemble each other;
• and
• a computer-readable second program code module for causing a computer to generate a signal stream based on
• (i) a combination of said first series of signals and said modulated series of signals if both of said first and second crank positioning sensors are operating,
• (ii) said first series of signals if said first crank positioning sensor is operating and said second crank positioning sensor is not operating, and
• (iii) said modulated series of signals if said second crank positioning sensor is operating and said first crank positioning sensor is not operating
• wherein a continuous stream of signals is generated that persists even in the event of operational failure of one of said first and second crank positioning sensors.