DBB5. DBB5
Circular tests by suing the ball bar measurement system (Double Ball bar, DBB) are widely accepted by machine tool builders to measure motion accuracies of conventional 3-axis machine tools. The application of ball bar tests to 5-axis machine tools has been lately studied by many researchers, and its inclusion in the revision of ISO standards has been currently discussed.
 
 
This project developed the modified DBB measurement device, called "DBB5" in our project, such that it can be applied to the accuracy calibration of a 5-axis machine tool in a more efficient manner with requiring less setup changes.
 
In DBB5, as illustrated below, the table-side ball is supported from the 45 deg direction, which makes it possible to perform 360 deg rotation on all of XY, YZ, and ZX planes with the same setup, avoiding the interference between the DBB bar and ball sockets. Its application to the diagnosis of various error sources in 5-axis machines has been currently studied in this project.
 
This project is organized by Prof. Yoshiaki Kakino of Kakino Research Institute. (March, 2009)
 
>> Publications: JJ12, CE39
 
 
 
Photo of DBB5.
 
Figure 1: A photo of DBB5 on a 5-axis machining center. A ball bar device by Heidenhain was modified.
 
 
 
Configuration of DBB5.
 
Figure 2: A schematic view of DBB5 measurement.