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This paper presents a new microrobotic platform actuated by capillary effects, combining surface tension and pressure effects. The device has 6 degrees of freedom (dof) among which three are actuated: z axis translation having a stroke of a few hundreds of microns, and θ x and θ y tilt up to about 15 •. The platform is submerged in a liquid and placed on microbubbles whose shapes (e.g. height) are driven by fluidic parameters (pressure and volume). The modeling of this new type of compliant robot is described and compared to experimental measurements. This work paves the way for interesting actuation and robotic solution for submerged devices in the microscale.

The parallel mechanism has become an alternative solution when micro manipulators are demanded in the fields of micro manipulation and micro assembly. In this paper, a three-Degree-Of-Freedom (3-DOF) parallel micro manipulator is presented, which is directly driven by three micro gas bubbles. Since the micro gas bubbles are generated and maintained due to the surface tension between the gas and liquid media, the proposed novel system can be used in the liquid environment which allows for rotation about X and Y axis and translation in Z axis. In this paper, the conceptual design of micro gas bubble-based parallel manipulator is introduced and the input/output characteristic of the actuator is analyzed in detail. The kinematics model of the parallel micro manipulator is also established, based on which the workspace and the system motion resolution are analyzed as a criteria and reference for future prototype development.

The context of this paper is to study the use of capillary microgripper in submerged mediums which requires the use of microbubbles. This paper presents a model and experimentations of the generation of bubbles. In the microsystems which uses liquid, gas bubbles can generate forces due to the surface tension at their interface. To use these bubbles, it is necessary to generate them in a controlled way. In this paper, we propose to study the generation of a bubble having a defined volume, using a syringe pump based device. We first build a mathematical model to predict the growth of the bubble in the liquid. Indeed, the compressibility of the gas and the effect of surface tension are of major importance at microscale, and our model will demonstrate the existence of an instability during the bubble growth. We proceed with a dimensionless study that will allow to predict the existence of the instability on the basis of a dimensionless number. Finally, we present experimental results to validate the mathematical model.

Minimally invasive surgeries on the lungs have eliminated the ability for surgeons to place their hands on the patient's organ to feel for abnormalities. Therefore, in this paper, a force sensor for 2 degrees of freedom haptic applications is described. Its integration within a force feedback teleoperated device would allow the medical doctor to essentially feel the lung without making physical contact. Its design relies on a specific elastic frame. The latter is based on two flexible structures bending around the same axis, in order to reduce cross-sensitivity. The manufacturing by wire electrical discharge machining allowed to obtain a monolithic, compact and highly precise structure.The force sensor has been sized on the basis of the study of the flexible parts it is made of. Next, it has been characterized and implemented on an haptic interface reproducing the contact with a human lung. The results show that the developed sensor is adequate to the study of lung palpation.