Finishing machine

A finishing machine for finishing a workpiece, which is arranged outside a robot, by the robot attached to a machining tool so that a shape of the workpiece can be close to a target shape, comprising:

• a force measurement means for measuring a force acting between the machining tool and the workpiece;
• a tracer control means for tracing a surface of the workpiece by using the force measurement means while the machining tool is being pushed onto the workpiece at a predetermined force;
• a surface shape acquisition means for acquiring a surface shape of the workpiece when a contact position of the machining tool with the workpiece is calculated from the position and posture of the machining tool, which is executing the tracing operation by the tracer control means, and the result of this calculation is recorded;
• a comparing means for comparing the surface shape of the workpiece, which has been acquired by the surface shape acquisition means, with the target shape;
• and
• a machining means for machining the workpiece while the position of the machining tool is controlled so that the workpiece shape becomes close to the target shape according to the result of comparison made by the comparison means,
• wherein the force measurement means is a force sensor attached to the robot, and the finishing machine operates while the machining tool and the workpiece positively come into contact with each other when force control is conducted using the force sensor in the process of executing tracer control;
• and
• wherein a force in the pushing direction is detected by the force sensor in the process of tracer control, and the contact position of the machining tool with the workpiece is corrected and recorded according to a flexure of the robot estimated by the detected force in the pushing direction.