Name: MANUEL RICARDO ALFONSO SANCHEZ
Publication date: 11/05/2020
Advisor:
Name |
Role |
|---|---|
| ANSELMO FRIZERA NETO | Advisor * |
| MARCELO EDUARDO VIEIRA SEGATTO | Co-advisor * |
Examining board:
| Name |
Role |
|---|---|
| ANSELMO FRIZERA NETO | Advisor * |
| CARLOS EDUARDO SCHMIDT CASTELLANI | Internal Examiner * |
| MARCELO EDUARDO VIEIRA SEGATTO | Co advisor * |
| MARIA JOSE PONTES | Internal Examiner * |
Summary: Conventional technologies to monitor kinetic and comfort variables in robotic exoskeletons and in human-robot interfaces are in general: bulky, sensitive to misalignments and do not allow for multiplexed operation. Optical sensors based on fiber Bragg gratings are a robust sensing approach that are desirable for multi-parametric and multiplexing monitoring, suitable for applications as in the rehabilitation monitoring and assistive technologies, with different type and brand of sensors adapted to people with physical disabilities or in robotic devices susceptible to forces, temperature variations, vibrations, and electromagnetic interference. Aiming to simplify the conventional instrumentation systems and to overcome some of its disadvantages, this work proposes new sensing solutions bringing two approaches for torque, angle and microclimate monitoring. A measurement platform developed in this work allows the acquisition of torque and angle of deformation in a torsion spring installed as an elastic element of a serial elastic actuator, used in the joints of the robotic exoskeleton developed in the TAO project, a partnership between UFES, USP-São Carlos, UnB and UFRN. The experimental configuration with the spring and a matrix of two FBGs is submitted to repeated torques and angles to validate its behavior. A platform for comfort measurement at the human-robot interface has also been proposed based on the use of a coating with hygroscopic properties that allows the quantification of relative humidity with Bragg gratings, intrinsically insensitive to this parameter. The proposed sensors have intrinsic sensitivity to temperature and strain variations. The compensation technique for unwanted effects uses an FBG in the vicinity of the measurement site, dedicated exclusively to temperature measurement. From the development of parts manufactured by 3D printing, it was possible to capture the relative humidity and temperature near the skin of two voluntary users. The developed sensors showed high linearity and low error for the measurements of force, angle, torque, and relative humidity.
