Semester projects proposal – Spring 2019

Integrated actuators – Prof. Y. Perriard

Note: Projects are intended for Microengineering, Electrical Engineering, Computer Science and Mechanical Engineering sections.

For information and registrations:

  • Prof. Y. Perriard, LAI, Rue de la Maladière 71B, CP 526, CH-2002 Neuchâtel 2, Office MC A4 298, phone number: 021.695.43.10, e-mail : yves.perriard@epfl.ch
  • P. Germano, LAI, Rue de la Maladière 71B, CP 526, CH-2002 Neuchâtel 2, Office MC A4 208, phone number: 021.695.42.33, e-mail : paolo.germano@epfl.ch

A fixed rate of CHF 600.- for transportation and meal expenses will be granted to each student doing its semester project at LAI on Microcity site in Neuchâtel.

1. Smart Gripper: Design and fabrication of a Miniaturised Shape Memory Alloy gripper prototype / S. Thomas

Assigned project

Grippers, currently used in Industry, are not suited for clean room application. Thus, a novel type of smart gripper is being designed using Shape Memory Alloys (SMA). In the development of this Smart Gripper, the modelling of the material is quite critical. The aim of this project would be to design a working test bench so as to characterize the material based on its transition temperatures and stress-strain behaviours.

The student must find an appropriate test bench solution that would be adapted to model the SMA sheet. The test bench must be able to heat the SMA as well as measure the resulting displacement and force.

This project will allow the student to learn the intricacies and the basics of prototyping as well as test their creativity and design acumen while building a test bench and proof of concept prototypes.

Keywords: Shape Memory Alloy, Design, Fabrication, Gripper

2. Improvements of a self-sensing piezoelectric actuator test bench / L. Masson

A test bench has been designed to experiment with self-sensing piezoelectric actuators. These transducers are capable of providing nm-µm scale displacements and that can manipulate objects at this scale, while simultaneously providing a feedback on position or force without the need for external sensors.

Improvements must be made on the test bench, and one of the most challenging aspects until now has been the charge measurement using a Keithley 6517A electrometer, due to the presence of leakage currents, bias currents and EM interference. In this project, the student will need to:

– Learn how to use this electrometer to measure charges in the range of pC to nC

– Design, assemble and test a PCB for the measurement connections with proper shielding

– Integrate his design into the complete test bench and demonstrate accurate charge measurement.

3. Magnetic Levitation Demonstrator / P. Peralta

At LAI, a micro motor with (a two degrees of freedom) magnetic bearing is being developed in collaboration with a Swiss company.

The first approach towards the control of a magnetic bearing is the successful levitation of an object in a single axis. The construction of a single axis magnetic levitation demonstrator is thus proposed.

The work will demand the optimization of a determined levitator geometry. A demonstrator with stiff levitation, long airgaps and low power consumption is to be optimized with the help of computational simulations.

4. High Stiffness Magnetic Bearing / P. Peralta

Assigned project

At LAI, a micro bearingless motor system is being developed, in collaboration with a Swiss company. The developed motor must support vibrations, axial and tilting loads.

Given the millimetric scale of the motor, a proper bearing design is of paramount importance for reliable operation. This work will thus focus towards the optimization of a determined motor topology, striving for bearing performance.

 5. Magnetic Bearings with Simplified Power Electronics / P. Peralta

At LAI, a bearingless motor is being developed with the support of a Swiss company. The integration  of a magnetic bearing will however increase control complexity and the power electronics of the system.

In this work, two topologies which enable simple control schemes will be presented. These will then be analyzed through computational simulations. Ultimately, their performances will be compared to individuate the best variant.

6. Development of a CNC Surface vibration scanning system / P. Germano, C. Hernandez

Assigned project

The EPFL – LAI Is investigating novel haptic technologies for rendering rich vibrotactile feedback in digital musical interfaces. The main objective is to develop an interactive surface that is able to render a multi-touch vibrotactile stimulus using piezoelectric actuators and wave focusing strategies. Scanning the surface to obtain the peaks and displacement is key during the development and characterization of the whole system.

Seeing that, the goal of this project is to develop a system that can measure the small vibrations (in the order of 2 – 20 um) that are produced in the different points of a surface, when different waveforms are transmitted to the surface using piezoelectric transducers.

This project will allow you to get hands-on experience with the software and hardware integration of a 3 axis CNC table, a waveform generator, a laser Doppler vibrometer, and an oscilloscope.