Design, fabrication and mechanical optimization of multi-scale anisotropic feet for terrestrial locomotion

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 67-69).Multi-scale surface interaction methods have been studied to achieve optimal locomotion over surface features of differing length scales. It has been shown that anisotropy is a convenient way of transferring an undirected force to a preferred direction or movement. In this thesis, the fundamentals of friction were studied to achieve a better understanding of how to design multi-scaled robotic feet that use anisotropy for terrestrial locomotion. Static and kinetic friction coefficients were found for novel test geometries under varying load conditions. The test geometries were manufactured with materials of variable durometer and were tested using unconventional rheometry methodology. Test results were then compared to standard friction laws. As predicted, the effects of contact area were shown to have an effect on the friction forces experienced by the softer materials. The contact area effects were then modeled as Hertzian contacts for a given material. Verification of the area dependencies for the materials with adhesive effects was performed for the samples used in the friction tests. The samples were subjected to varying compressive force and images of the corresponding contact areas were obtained using an inverted microscope. The microscope images were then processed using MATLAB's image processing toolbox to find the actual contact area for the samples. The contact area results were shown to be in accordance with Herztian contact principles. The effects of varying surface roughness were also studied for a given anisotropic arrangement of bristles. The array of bristles was used to provide propulsion to a controllable robot called BristleBot. The untethered nature of the robot allowed for unhindered velocity and force measurements that were used to analyze the effects of surface roughness. The force input for the robot was provided by two vibration motors that created an excitation which was then translated to horizontal movement by the anisotropic formation of the bristles. It was found that the BristleBot was able to achieve optimal locomotion when roughness conditions were minimized. Results of the anisotropic friction and adhesion tests were used to improve footpad development for soft robotic platforms.by Jeffrey W. Morin.S.M

Designing to Support Workspace Awareness in Remote Collaboration using 2D Interactive Surfaces

Increasing distributions of the global workforce are leading to collaborative workamong remote coworkers. The emergence of such remote collaborations is essentiallysupported by technology advancements of screen-based devices ranging from tabletor laptop to large displays. However, these devices, especially personal and mobilecomputers, still suffer from certain limitations caused by their form factors, that hinder supporting workspace awareness through non-verbal communication suchas bodily gestures or gaze. This thesis thus aims to design novel interfaces andinteraction techniques to improve remote coworkers’ workspace awareness throughsuch non-verbal cues using 2D interactive surfaces.The thesis starts off by exploring how visual cues support workspace awareness infacilitated brainstorming of hybrid teams of co-located and remote coworkers. Basedon insights from this exploration, the thesis introduces three interfaces for mobiledevices that help users maintain and convey their workspace awareness with their coworkers. The first interface is a virtual environment that allows a remote person to effectively maintain his/her awareness of his/her co-located collaborators’ activities while interacting with the shared workspace. To help a person better express his/her hand gestures in remote collaboration using a mobile device, the second interfacepresents a lightweight add-on for capturing hand images on and above the device’sscreen; and overlaying them on collaborators’ device to improve their workspace awareness. The third interface strategically leverages the entire screen space of aconventional laptop to better convey a remote person’s gaze to his/her co-locatedcollaborators. Building on the top of these three interfaces, the thesis envisions an interface that supports a person using a mobile device to effectively collaborate with remote coworkers working with a large display.Together, these interfaces demonstrate the possibilities to innovate on commodity devices to offer richer non-verbal communication and better support workspace awareness in remote collaboration

Firefighting Remote Exploration Device II

The need for “smart” recovery for disasters is at the forefront. Firefighters operating in indoor firegrounds are put at risk by the constantly changing environment. The use of robotics in firefighting can assist firefighters by informing them about different aspects of the fireground, such as the structural layout and temperature distribution. Taking inspiration from a design devised by a previous WPI Major Qualifying Project, our team prototyped a heat, water, and impact-resistant robot capable of navigating around obstacles in the fireground and returning relevant real-time data

Interconnects and Packaging to Enable Autonomous Movable MEMS Microelectrodes to Record and Stimulate Neurons in Deep Brain Structures

abstract: Long-term monitoring of deep brain structures using microelectrode implants is critical for the success of emerging clinical applications including cortical neural prostheses, deep brain stimulation and other neurobiology studies such as progression of disease states, learning and memory, brain mapping etc. However, current microelectrode technologies are not capable enough of reaching those clinical milestones given their inconsistency in performance and reliability in long-term studies. In all the aforementioned applications, it is important to understand the limitations & demands posed by technology as well as biological processes. Recent advances in implantable Micro Electro Mechanical Systems (MEMS) technology have tremendous potential and opens a plethora of opportunities for long term studies which were not possible before. The overall goal of the project is to develop large scale autonomous, movable, micro-scale interfaces which can seek and monitor/stimulate large ensembles of precisely targeted neurons and neuronal networks that can be applied for brain mapping in behaving animals. However, there are serious technical (fabrication) challenges related to packaging and interconnects, examples of which include: lack of current industry standards in chip-scale packaging techniques for silicon chips with movable microstructures, incompatible micro-bonding techniques to elongate current micro-electrode length to reach deep brain structures, inability to achieve hermetic isolation of implantable devices from biological tissue and fluids (i.e. cerebrospinal fluid (CSF), blood, etc.). The specific aims are to: 1) optimize & automate chip scale packaging of MEMS devices with unique requirements not amenable to conventional industry standards with respect to bonding, process temperature and pressure in order to achieve scalability 2) develop a novel micro-bonding technique to extend the length of current polysilicon micro-electrodes to reach and monitor deep brain structures 3) design & develop high throughput packaging mechanism for constructing a dense array of movable microelectrodes. Using a combination of unique micro-bonding technique which involves conductive thermosetting epoxy’s with hermetically sealed support structures and a highly optimized, semi-automated, 90-minute flip-chip packaging process, I have now extended the repertoire of previously reported movable microelectrode arrays to bond conventional stainless steel and Pt/Ir microelectrode arrays of desired lengths to steerable polysilicon shafts. I tested scalable prototypes in rigorous bench top tests including Impedance measurements, accelerated aging and non-destructive testing to assess electrical and mechanical stability of micro-bonds under long-term implantation. I propose a 3D printed packaging method allows a wide variety of electrode configurations to be realized such as a rectangular or circular array configuration or other arbitrary geometries optimal for specific regions of the brain with inter-electrode distance as low as 25 um with an unprecedented capability of seeking and recording/stimulating targeted single neurons in deep brain structures up to 10 mm deep (with 6 μm displacement resolution). The advantage of this computer controlled moveable deep brain electrodes facilitates potential capabilities of moving past glial sheath surrounding microelectrodes to restore neural connection, counter the variabilities in signal amplitudes, and enable simultaneous recording/stimulation at precisely targeted layers of brain.Dissertation/ThesisMasters Thesis Bioengineering 201

Haptic Interactions with Virtual Reality

Many possible systems exist that could benefit from Haptic Interactions, the communication of forces between a user and a system. Robotic assisted rehabilitation, interactive Virtual Reality media, and Telerobotics are some examples. However, due to simplified interactions methods, high costs, and lack of application development tools, Haptic Interaction with Virtual Reality has not reached its full potential. As a solution towards these problems, the team created a development platform Haptic Interaction System, capable of supplying Haptic Interactions between a user and hosted simulated environment and objects, along with the tools to enhance the system and develop applications based on Haptic Interactions

Building E-education platform for design-oriented learning

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.Includes bibliographical references (p. 149-155).Design-oriented learning requires tools that support creative processes and student-to-student and student-to-faculty interactions. While most present E-Education systems perform as the asynchronous distribution channel for teaching material, they usually offer little support for project based design processes. This research maps out the key learning events in design classes at MIT's Department of Mechanical Engineering, and proposes guidelines for building E-Education systems to support the unique characteristics of design-oriented learning. Two creative learning processes are identified and two independent, yet tightly related, software systems are implemented and evaluated. The first application, the Peer Review and Engineering Process (PREP), is a web system that helps instructors and students conduct and manage peer review evaluation of design concepts. The second is a real time application called InkBoard that leverages the Tablet PC and Ink medium to provide real-time collaborative sketching over TCP/IP networks. A new streaming network protocol for transferring Ink objects is proposed and implemented. A comparative study against other ink-enabled protocols is also presented.by Hai Ning.Ph.D

Marine Robot Sample Retrieving System

The exploration of our underwater ecosystems is critical. The aquatic ecosystem has a significant effect on human life, yet our understanding of the oceanic environment is severely lacking. Santa Clara University’s Robotic Systems Lab contributes to subsea exploration through its investment in remotely operated vehicle (ROV) technology. This project was done with the guidance of not only professors in the Robotics Systems Lab, but also stakeholders from the US Geological Survey scientists and researchers from the Monterey Bay Aquarium Research Institute (MBARI). Our team goal was to further advance SCU’s efforts by creating a sediment sample collection system consisting of a manipulator arm and sample storage container compatible with an existing SCU ROV. Our project has the potential to give researchers better access to submerged ecosystems and assists their efforts to understand and protect subsea environments in the future. We designed, built, and tested a prototype of a multiple degree-offreedom arm and storage system for the existing Nautilus ROV, for safely manipulating and storing submerged sedimentary artifacts at 300 feet deep with a maximum dive time of 45 minutes. At the end of this project, we were able to see robust three degree of freedom movement of the arm within its anticipated workspace. We achieved a basic level of motion control of the arm which was successfully tested and evaluated within a testing tank. However, there is still need for additional testing and increased functionality of the mechanical and controls systems. The storage system for samples design needs a thrust bearing to better rotate and there is still much work to make the controls of the arm user friendly such as end effector control for depositing a sample into the storage system instead of doing all the movements manually