Comparison of Two Prominent Approaches in Tactile Whisker Sensor Systems for Texture Perception and Force Directional Sensing

Author: Abdul Salam Manakkadavath

Manakkadavath, Abdul Salam, 2024 Comparison of Two Prominent Approaches in Tactile Whisker Sensor Systems for Texture Perception and Force Directional Sensing, Flinders University, College of Science and Engineering

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Abstract

This study investigates the design and performance of tactile whisker sensor systems for texture detection and directional force sensing in mobile robotics. The primary objective is to compare two prominent sensing methods: stress measurement at the base and strain measurement along the side of the whisker. The project aims to implement a design as a supplementary or alternative solution to conventional sensors such as LIDAR, ToF cameras, and SONAR. The requirements are to measure surface texture features with a whisker shaft length of at least 200 mm, resolve surface features of a texture with an average gap size and amplitude of 60 µm, and achieve a force direction sensing capability with an average error margin of less than 0.3 degrees. The hypothesis is that setting up the sensing element at the side will resolve the gap size of the texture features more accurately, while setting up the sensing element at the base will resolve the amplitude more accurately. Dynamic simulations were conducted using Ansys workbench motion tool to analyse texture detection, while static analysis was performed in the Ansys workbench static structural to analyse the whisker design's force-directional sensing capability. In both cases, Stress was probed from the whisker's base and strain from the sides. The results indicated that Stress sensing at the base resolved the texture amplitude more accurately than the strain probed at the sides, and strain sensing at the sides resolved gap sizes better than measuring stress at the base of the whisker. Regarding directional force sensing, stress measurements at the base achieved a 0.1-degree resolution but were limited by the sensors' limitations and the whisker length. Strain probing at the side, although limited by sensor noise for the sensor considered, demonstrated potential for higher force detection, thus requiring further exploration by using different sensors. The results showed that the whisker design considered resolved texture features with a 60 µm amplitude and 50 µm gap size for the strain probed from the side, while the texture surface with a 40 µm amplitude and 90 µm gap size was resolved by probing the Stress from the base of the whisker. These results agree with the hypothesis made. Future work includes extending dynamic simulations to varying whisker dimensions and experimental validation using physical prototypes.

Keywords: Ansys, Dynamic analysis, LIDAR, Mobile robotics, motion tool, SONAR, Static analysis, Tactile whisker, Tactile sensors, Texture detection, ToF cameras, workbench, Whisker.

Subject: Engineering thesis

Thesis type: Masters
Completed: 2024
School: College of Science and Engineering
Supervisor: Russell Brinkworth