A flexible microrobotic platform for handling microscale specimens of fibrous materials for microscopic studies

Abstract

SummaryOne of the most challenging issues faced in handling specimens for microscopy, is avoiding artefacts and structural changes in the samples caused by human errors. In addition, specimen handling is a laborious and time-consuming task and requires skilful and experienced personnel. This paper introduces a flexible microrobotic platform for the handling of microscale specimens of fibrous materials for various microscopic studies such as scanning electron microscopy and nanotomography. The platform is capable of handling various fibres with diameters ranging from 10 to 1000 µm and lengths of 100 µm-15 mm, and mounting them on different types of specimen holders without damaging them. This tele-operated microrobotic platform minimizes human interaction with the samples, which is one of the main sources contributory to introducing artefacts into the specimens. The platform also grants a higher throughput and an improved success rate of specimen handling, when compared to the manual processes. The operator does not need extensive experience of microscale manipulation and only a short training period is sufficient to operate the platform. The requirement of easy configurability for various samples and sample holders is typical in the research and development of materials in this field. Therefore, one of the main criteria for the design of the microrobotic platform was the ability to adapt the platform to different specimen handling methods required for microscopic studies. To demonstrate this, three experiments are carried out using pooya.saketi@tut.fi the microrobotic platform. In the first experiment, individual paper fibres are mounted successfully on scanning electron microscopy specimen holders for the in situ scanning electron microscopy diagonal compression test of paper fibres. The performance of the microrobotic platform is compared with a skilled laboratory worker performing the same experiment. In the second experiment, a strand of human hair and an individual paper fibre bond are mounted on a specimen holder for nanotomography studies. In the third experiment, individual paper fibre bonds with controlled crossing and vertical angles are made using the microrobotic platform. If an industrial application requires less flexibility but a higher speed when handling one type of sample to a specific holder, then the platform can be automated in the future.

Vision based event classification in robotic micromanipulation

“…Fig. 2 illustrates the two example events (labels in the feature matrix) which were selected for evaluating the different classification methods: (1) an event where the chip is being grasped (grasped-event) and (2) an event where a chip is adhered to a gripper tip (adhered-event) during its release.…”

“…These methods have been applied in handling of single fibers [2]- [4], construction of complex micromechanical structures [5], automatic inspection of microelectronic components [6], manipulation of single microscopic biological organisms [7], etc. In the micromanipulation environment, the objects are often fragile and can be deformed easily.…”

Numerical evaluation of interfibre joint strength measurements in terms of three-dimensional resultant forces and moments

“…Recently, a novel method for making and manipulating fibre-fibre crosses using a micro robotic grip system was presented by Saketi et al [11]. Their method allows preparing fibre-fibre crosses in a controlled manner, in terms of the crossing angle and shape factor, but, unfortunately, no measure of the force during testing was reported.…”

Automated Assembly of Vascular-Like Microtube With Repetitive Single-Step Contact Manipulation

“…Flexible, high-precision microrobotic assembly can be realized by contact micromanipulation techniques, because mechanical contact with the microstructure is established without electrical or optical interference by the ambient environment [15]- [17]. Kimura et al [18] developed one of the earliest contact micromanipulation systems for cell injection, and Dario et al [19] proposed a prototype of microassembly system for medical microdevices.…”