Development of a Vise with built-in Piezoelectric and Strain Gauge Sensors for Clamping and Cutting Force Measurements

Accurate measurement of static and dynamic forces during machining operations is important in the process monitoring, optimization and prediction of machining quality. Cutting and clamping forces are typically measured separately, for example, through hydraulic clamping force devices and piezoelectric table dynamometers. Since cutting and clamping forces interact throughout machining, both forces need to be measured simultaneously to accurately predict machining quality. This paper proposes a novel force measuring device in the form of a vise with built-in piezoelectric sensors and strain gauges to measure multi-axial clamping and cutting forces simultaneously. A strain concentrating design based on a cross-shaped groove was utilized to attach three strain gauges to measure clamping forces. These locations were chosen for their ability to measure clamping forces in real-time and minimize cross-talks. Piezoelectric sensors were embedded between layers in the vise jaw to measure cutting forces. A prototype of the proposed apparatus was fabricated and used to experimentally investigate sensitivities, bandwidth, clamping forces and cutting forces. The results showed that the proposed device has good performance in measuring clamping and cutting forces in milling operations.