Simulation and experimental evaluation of laser-structured actuators for a mobile microrobot

Abstract

This paper describes the simulation, fabrication and evaluation of a mobile platform's actuator, which is the foundation for microrobots. The working principle is based on the mobile platform RollBot. The new feature is the combination of three rolling steel spheres driven by three laser structured piezoactuators, each containing three ruby hemispheres. Because of the piezoactuator's special design, the hemisphere's stick-slip displacements decrease and enable a more precise control. The platform's properties concerning rigidity, resolution and maximum velocity improve. After an introduction of RollBot's and the new actuation principle, a short description of the laser structuring process is given. Several Finite-Element(FE)-simulations are presented to understand the expected performance of the mobile platform. Finally, measurements of step sizes and maximum velocities are shown. The application of the actuator in a mobile platform proves the derived properties.

Open Loop Force Control of Piezo-Actuated Stick-Slip Drives

“…Alternation of both phases is used to displace the runner with travels larger than the static displacement. For detailed descriptions of the principle the reader is referred to literature (Breguet, 1998;Edeler, 2008;Driesen, 2008).…”

“…cies should be as high as possible. This can only be reached by a stiff design (Breguet, 1998;Edeler, 2008). But even if this is done, the slip signal is almost a kind of unit step and therefore the whole frequency spectrum is theoretically excited (Edeler, 2010).…”

“…An almost all-embracing classification and description of mobile nanohandling robots can be found in Driesen (2008). Appreciable examples were published by the group of Fatikow (Edeler, 2008;Jasper & Edeler, 2008). The center of gravity is on the automation of the robots as part of nanohandling scenarios.…”

High-Speed Nanorobot Position Control Inside A Scanning Electron Microscope

“…1). The mobile nanohandling robots used in this paper have been extensively described in several publications [7], [11], [12]. Mobile robots have several advantages over Cartesian systems with multiple linear positioners.…”

“…Due to the fact that ruby hemispheres and hardened spheres from ball bearings are used, wear is negligible. This is the main motivation for the robot's design [11]. Notice that most of the mentioned effects are of nonlinear character.…”