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This paper presents a non-contact manipulation method using rotational flow generated by high speed motion of a glass needle. In order to generate an applicable motion that can precisely control the speed and position of a target object around an end effector, a manipulator actuated by three piezoelectric actuators is proposed. A compact parallel link produces precise three-dimensional motions. To reach the required end-effector frequency and amplitude, which is necessary for generating the rotational flow that can make rotational movement of microbeads having patterned data, the end effector motion is generated by controlling the three piezoelectric actuators at high speed. In this paper, we focus on rotational flow created by two-dimensional circular motion of the end effector mounted on the parallel link. By changing the amplitude and frequency of the circular motion, the generated swirl flow is analyzed in 3D space using 9.6-μm microbeads. We analyzed the velocity toward to the root of the end effector and angular velocity around the end effector by formulating models. From the analyzed data, we verified that the rotational flow has potential to manipulate micro-objects precisely in 3D space. [ABSTRACT FROM AUTHOR]

In this paper, we present a high-speed pick-and-place method for cell-assembly applications. In addition to the range of motion and accuracy, the agility of a manipulation system is an important parameter, but it has been so far underrated in the literature. To begin high-speed micromanipulation, obtaining 3-D positions of both the target microobject and the end effector rapidly is necessary. Controlling the residual vibration of the end effector, which is greater at high speed, is another arduous task. Successful releasing of objects in microscale is also demanding. We propose a new fast detection algorithm for both the target microobject and the end effector, which will enable us to achieve high-speed control of the system. Moreover, to realize stable grasping for very fast movements, the vibration of the system is compensated, and a controllable vibration is applied to the end effectors while performing the releasing task. High-speed control of the microhand system is demonstrated with extensive experiments consisting of pick-and-place actions of 40–60 \mu\m microspheres; we aimed at performing the task in 1 s. A comparison with similar studies shows the advantage of the proposed automated high-speed micromanipulation system. [ABSTRACT FROM PUBLISHER]

Abstract-The development of a chopstick-like two-fingered micromanipulator based on a hybrid mechanism is presented. The microhand consists of two 3-prismatic-revolute-spherical (PRS) parallel modules connected serially in a mirror image style. Each module has a long glass pipette as an end effector. The development process consists of three phases. In the first phase, analysis and mathematical modeling, a novel solution of the inverse kinematics problem (IKP) of a 3-revolute-prismatic-spherical (RPS) parallel module, is derived and applied with proper modification to the case of 3-PRS of the proposed mechanism. The solution is extended to the two-fingered hybrid mechanism of the microhand. In the optimization and design phase, the optimization of the chosen design parameters of a theoretical 3-PRS parallel module is carried out using two approaches: discretization method and genetic algorithms. Based on the optimal design parameters, a CAD model of the 3-PRS finger module is built, and a complementary optimization step using the ANSYS Workbench program is carried out to determine suitable characteristics of the pin fiexure hinge. Finally, the total CAD model of the two-fingered hand is built. In the realization and implementation phase, the description of the hardware system of the two-fingered microhand prototype is presented. The program description, calibration method, practical Jacobian matrices, practical workspace, and error analysis of the prototype are discussed. [ABSTRACT FROM AUTHOR]

To assemble microobjects including biological cells quickly and precisely, a fully automated pick-and-place operation is applied. In micromanipulation in liquid, the challenges include strong adhesion forces and high dynamic viscosity. To solve these problems, a reliable manipulation system and special releasing techniques are indispensable. A microhand having dexterous motion is utilized to grasp an object stably, and an automated stage transports the object quickly. To detach the object adhered to one of the end effectors, two releasing methods—local stream and a dynamic releasing—are utilized. A system using vision-based techniques for the recognition of two fingertips and an object, as well automated releasing methods, can increase the manipulation speed to faster than 800 ms/sphere with a 100% success rate (N = 100). To extend this manipulation technique, 2D and 3D assembly that manipulates several objects is attained by compensating the positional error. Finally, we succeed in assembling 80–120 µm of microbeads and spheroids integrated by NIH3T3 cells. [ABSTRACT FROM AUTHOR]