Abstract: An automated welding apparatus (20) supports a work head (30) for motion in at least two dimensions along a seam (24) in a work piece (21). A tactile sensing probe (33) is mounted to the work head (30) to rotate about it and is controlled so that the tip (35) of the probe is in contact with a wall (26) of the seam at a constant force or deflection. The position of the probe (33) as it contacts the seam wall is sampled and stored to establish a data base for the geometry of the seam wall, and the work head (30) is then driven to follow the established data base while the probe (33) precedes it acquiring new data for the seam wall geometry. The work head may include a welding head (31) rotatable about an axis which can be controlled to be directed at a constant angle with respect to a normal to the seam wall.

Abstract: A system for monitoring the performance of an internal combustion engine includes a pressure sensor that has a mounting configuration external to the cylinders such that it is capable of monitoring the pressures within two adjacent cylinders. The signal output of the sensor is filtered to remove undesired engine noise and blank out those signals which are unrelated to compression and firing, thereby reducing errors in the signal output. After filtering the signals to reduce noise, a successive number of samples related to compression and firing are obtained to provide an adequate number of signals which will average out mechanical and electrical noise. From the successive samples, a straight line approximation of the slope of the cylinder pressure curve, relative to crank angle, is obtained. The derived slope values are compared with upper and lower limits to determine whether or not the pressure within the engine cylinder of interest is acceptable.

Abstract: This invention relates to controlled apparatus having a tool including a plurality of directions of movements with the directions interrelated, such as an arc welding unit having an electrode for contouring of similar work parts along a seam contour. The apparatus includes a logic system and memory such as a computer and a tracer to follow an original contoured curve or shape in space and generate a position-related signal. The computer includes a self-programming program in memory in which control program particulars of a contour are generated and introduced by an initial movement of the tracer over an original contour under a closed-loop position control program in a trace-record mode. During the trace-record mode the computer reads the necessary inputs and creates a set of data at points along the contour. The data sets are fitted together by a spline function (third-degree polynominal) to produce a close approximation of the weld seam in its multi-dimensions.