Automated Drop-on-Fiber contact angle measurement using a microrobotic platform

Autor: Pasi Kallio, Christian Ganser, Pooya Saketi, Pedro Fardim, Joakim Järnström, Christian Teichert, Yuli Lai, Juha Hirvonen
Rok vydání: 2014
Předmět:
Zdroj: ResearcherID
ISSN: 2000-0669
0283-2631
Popis: Measuring contact angles on single fibers enables the separation of structural factors from surface chemistry factors. Current Drop-on-Fiber (DOF) contact angle measurement methods for natural fibers generally, and for pulp/paper fibers specifically, present a number of challenges. These are manipulation and mounting of the microscale fibers, straightening natural fibers to produce repeatable axisymmetric droplet conformation, measuring the droplet volume excluding the fiber volume and also human errors due to manually performed tasks. This paper presents a novel method to measure contact angles in DOF systems and overcome the above mentioned challenges using microrobots. The proposed microrobotic platform is capable of handling natural and synthetic fibrous materials in microscale, and dispensing probe liquid droplets down to 12 nl. It measures contact angle values using computer vision and a droplet-profiledetection algorithm. It reports the contact angle values as a function of volume of the droplet. The paper validates the capabilities of the proposed platform by applying three commonly used probe liquids: deionized water, ethylene glycol and diiodomethane for measuring contact angles on glass and pulp fibers. Finally, the results are compared with a picoliter contact angle measurement approach.
Databáze: OpenAIRE