When the boom of a construction machine is processed by an opposed horizontal boring
machine, the hole position is measured using a touch sensor. However, this measuring time is a
bottleneck in the enhancement of productivity and therefore the improvement of the measurement
speed is desirable. Mitsubishi Heavy Industries, Ltd. (MHI) developed a contactless hole position
measurement system and realized the enhancement of productivity through a reduction of the
process time. This measurement system offers an optimum processing algorithm for workpieces
that have various disturbance factors at customer machining sites to realize high robustness. This
paper presents specific issues in improving the robustness of a contactless measurement system
and their solutions, as well as the automatic hole position offset function that can eliminate manual
intervention.
