'Test Plan - What to Test'
- Test serial communication procedures between computer and stepper motors. Should be able to achieve complete control of stepper motors from computer.
- Handling routine, based off simulated rivet data and real parts. Routine should be able to correctly identify locations of rivet features, and perform data manipulation to obtain measured results.
- Test part holding chuck fixture. Must be easy to load/unload, and hold parts at a repeatable position.
- Test linear and rotational motion. Program must be able to drive stages appropriate distances at specified times. Program must be able to communicate with micrometer, to send commands and receive measured values.
- Calibration routine. Routine should be highly automated, with little input from operator. Refer to Keyence LS series owners manual, Chapter 4 - Calibration Settings, for details of 2-point calibration procedure. Develop additional sequence for calibrating length-wise measurements, to account for variations in lead screw pitch and motion stage. Specific calibration hardware TBA and to be purchased early in MSD2.
- Final testing of complete system. Finalize calibration routine and user interfaces. Expand capabilities to several different rivet models.
'How We Tested'
Serial Communication between Computer and Stepper Motors
- Used preexisting software provided by The Motion Group in order to establish communication between the motors and computer.
Data Handling Routine based on simulated rivets and real parts
- Simulated rivet routine relied on mostly user inputs in order to find rivet features within the scanned data.
- Real part data handling routine was able to read actual rivet specs from a preexisting excel file in order to find rivet features. Requires no user input other than selecting proper file to read specs from.
- Once arbor modification were complete and the chuck was fastened, several actual rivets were placed into the chuck and measured for depth. Chuck held all rivets the same depth inside and held them completely parallel and steady
- First test results:
- Added second stage block for balance and stabilization of the linear stage.
- Replaced bearings with self-aligning linear bearings at all four contact points for smoother
- Adjusted the position of the anti-backlash nut to improve the alignment of the lead screw
- Second test results:
- Once the rotational setup was constructed and working mechanically, there were no adjustments made to change how the data was acquired. Measurements were taken was part of the complete system LabVIEW scan.
- A LabVIEW run sequence was written in order to check the calibration of the machine. Using a precision gauge pin, known data was entered with desired tolerances. As long as the measures fell within the tolerance lengths and diameters, the system was in proper calibration.
- Final test of the system was a complete rivet scan using the LabVIEW sequence written. Data was recorded, linear data was scanned the image was plotted as well as the rotational data.
Preliminary Gauge R&R
- 3 operators, 3 different rivets, 3 trials
- Data was taken to measure the repeatability of the Rivetron. Data was also taken in a comparitor to measure the accuracy of the Rivetron.
CAD Drawings | Fabrication | LabVIEW Programming | Rivetron Owner's Manual