Research On Turning Force Measurement System Based On Fiber Bragg Grating Sensor

With the accelerating development of industrial automation and modern manufacturing, numerical control machine and machining center have become the mainstream of modern manufacturing technology. In order to guarantee the safe operation and processing quality of these high-cost automatic processing equipments, it is in urgent need of new, practical and reliable monitoring system to monitor the dynamic cutting process of processing system and forecast the tool wear and fracture conditions. Cutting process is primarily involves cutting parameters and tool condition, with the purpose of enhancing productivity and reducing production costs, under full automatic processing environment, the effective monitoring of tool conditions is the nucleus of machine tooling monitoring as well as the research hotspot. Currently, in the field of tool condition monitoring, the measurement of turning force is the most popular method. It can straightly reflect the tool conditions during course of working and detect tool wear and fracture conditions.Fiber grating sensor is a new flash ranging sensor. It characterizes by small volume, explosion prevention, electric insulation, anti-electromagnetic interference, high precision, high reliability, excellent environment suitability and the grating can deploy in a single fiber several measurements directed at different or similar parameters to form distributed transduction, which satisfy the requirements of multiple components of turning force in conducting on-line monitoring, adapt to the processing environment of turning force measurement so as to realize the accurate measurement. Given this background, this paper puts forward the application of fiber grating sensor technology into tool cutting force measurement system. This paper has gained the following fruits:First, conversion elastomer is a sensitive component in measuring cutting force and it determines the testability of cutting force. Through the combined use of process research, theoretic analysis and simulation of finite element analysis into the numerical control machine cutting, this paper reveals the distribution rule'of conversion elastomer strain caused by cutting force, establishes the mapping relations between cutting force and elastomer strain, and proposes the structural optimization designing method of elastomer.Second, develop a set of cutting force measuring system based on fiber grating. Research thin-wall extended cutting force measurement system based on the strain gauges and fiber grating sensors, research the sensors arrangement. Complete thin-wall extended cutting force calibration experiment, contrast metrical data of strain gauges and grating sensors, Analysis the error reason and optimizate the position of the sensors. System integration based on fiber grating sensors and distributed detection technology in the CA6140 lathe conducts initial cutting experiment and a large number of experiments indicate that fiber bragg grating sensor can be a reliable method to measure turning force.