Automated Robot Improves Production Throughput for Nano-Dispensing Capillary Tubes
Precision is key in any industry, but especially in the medical field. When administering vaccines or medicine, doctors must make sure they are giving the correct amount, or the consequences could be detrimental. A local biotech company needed to expedite their process of creating glass capillaries to be used for nano-dispensing. Cyth worked on the micron level to create an automated robot system to treat the raw glass capillary, ensuring that it could be used in the most rigorous of medical and biotech lab environments.
Client Request & Cyth Solution Cyth engineers designed and developed an automated system using a robotic arm to treat the client’s glass capillaries in a very specific way. The treating process began with the robotic arm taking a raw capillary measuring 1-millimeter in width and 100-millimeters in length and placing it inside a device that would heat the middle of the capillary to an extremely high temperature. Once the glass capillary was hot enough, the devices pulls the capillary apart into two halves, in turn making it very thin and pointy on the inside ends. After measuring to a specific width, the system breaks the capillary at that point and grinds the end so it’s smooth and perpendicular in shape. It’s then placed under a microscope and the tip is forged and ready to be examined so it remains the correct measurements. It is then placed inside a pallet system of completed capillaries.
The largest piece of hardware was the robot table that all the stations were mounted onto. The client provided the end effector, or gripper, of the robot that grabs the capillaries. The sequence starts with a pile of raw glass, with a mechanism containing the pneumatics to present one single raw capillary to the robot so it can be grabbed in the same spot each time. This mechanism is called the “magazine” or the “singulator”. Cyth’s engineers needed to integrate the singulator by controlling the pneumatics through several industrial digital outputs. They had a PXI with an industrial digital output and a power supply card, both connected to a computer with LabVIEW software completed on a Windows 10 PC. Three sensors indicate whether the singulator is up or down, and another sensor determines if the robot successfully grabbed the capillary.
To properly bend the capillaries, there is another station built on a separate bread board mounted on the table that contains two cameras; one is the microscope, known as “the high magnification”. The other camera is “the low magnification” and sits perpendicular to the other to capture a larger field of view of each capillary. The microscope is used for measurements, breaking, cleaning and forming the tip of the capillary, and the side camera is used for bending. Cyth also created two other stations; one used to grind each glass capillary without burning it and one to clean the capillaries using pressurized air. LabVIEW software was used to program the sensors that determined if there are extra palettes available, the location of those palettes and which holes on the palette are already occupied.
Challenge The largest obstacle throughout this project was how to move between positions without crashing, and to develop a system of named locations and allowed moves. Cyth’s engineers programmed the robot with steps preventing it from moving outside of its preset positions, so it wouldn’t throw off the entire system. The robot has an extremely fine gripper, and if the programming is off by just a few microns, it could crush the glass capillary instead of grabbing it properly. Since the capillaries were so small, there was also a few vision algorithm issues that came up when inputting the specific and accurate measurements. The capillaries are so tiny and fine-tipped they can break easily or be burned instead of molded. These challenges gave Cyth the opportunity to collaborate directly with the client’s and after discussing, troubleshooting, and trial and error, Cyth’s engineers were able to come to the best set of variables and produce an accurate, efficient system.
Outcome This client has such a high quote to fill when producing these delicate glass capillaries, and it was becoming impossible to produce them fast enough to fulfill high volume orders while still maintaining a high standard of quality. The objective was to produce the capillaries from raw to final product with no human interaction to assure they wouldn’t be contaminated and that the output would be as consistent as possible. Thanks to the persistence of Cyth’s engineers, the robot system also allows them to consistently build throughout a 24-hour period without needing operators to moderate, increasing efficiency and greatly multiplying their product volumes.
Technical Specifications • Newport Rigid Vibration Control System (99 x 1800 x 152 mm) • Dell Precision Workstation • PCI Ethernet card (4-port) • PXI-4113 – Triple output power supply for Filament and LED • PXI-6514 for Industrial Digital I/O • PXI-1033 4-Slot Remote Controlled chassis with MXI Control from PC • 900mm Denso VS087A4 with Pendant for programming • Newmark MSL Series Linear Stage Motor (200 mm travel, res. 0.2 mm) • Keyence Safety Light Curtain • High magnification microscope o FOV 500 microns x 800 microns • Low magnification camera o FOV 5 millimeters x 8 millimeters • LabVIEW 2017 (32-bit)