Hexagon Metrology S.p.a.

Giampiero Guasco

Michele Verdi

Domenico Russo

A method of calibration of a mathematical model for the compensation of errors due to dynamic deformation of a measuring machine equipped with a mobile unit able to move a stylus probe in un measuring volume, wherein the model provides, in response to at least one input quantity correlated with a control signal of said drive means, a plurality of output quantities comprising at least one component of the measurement error introduced by the deformation and at least one quantity detected by a laser sensor and correlated with the deformation. In the calibration step, the mobile unit is subjected to a movement cycle constituted by small-amplitude oscillations of variable frequency, following the law of sinusoidal motion, keeping the tip of the probe blocked; during the movement cycle, the input and output quantities are sampled and supplied to an algorithm for model identification.

Method of calibration of a mathematical model of a coordinate measuring machine for the compensation of dynamic errors due to deformation

A measuring machine includes a mobile unit to move a measurement sensor in a measurement volume. The mobile unit includes at least one member mobile along an axis under the thrust of driving means and being subjected to dynamic deformations. A laser sensor is provided with a laser emitter fixed to a first portion of the mobile member and a target fixed to a second portion of the mobile member and designed to receive a laser beam generated by the emitter. Means are provided for compensating for measurement errors of the machine resulting from the dynamic deformations of the mobile unit and in response to displacement of a point of incidence of the laser beam on the target with respect to a reference position in undeformed conditions, the displacement of the point resulting from the relative displacement of the first and second portions of the mobile member.

Compensation of measurement errors due to dynamic deformations in a coordinate measuring machine

A measuring machine comprising a measuring column, which can move vertically with respect to a carriage, and a device for balancing the weight of the column, which is provided with a pneumatic cylinder having its liner fixed to the column and the stem constrained to a supporting structure, carried by the carriage via an elastic-suspension assembly that enables the stem to follow the liner in the case of adhesion and to return into a position of equilibrium when the elastic reaction of the elastic-suspension assembly overcomes the force of friction between the piston and the liner; stick-slip phenomena are thus neutralized.

Growing community of inventors

Rivalta di Torino, Italy

Giampiero Guasco