Academic literature on the topic 'A-ARM'

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.<br>Includes bibliographical references (p. 61-62).<br>This thesis proposes and implements ANA, a new method for the simulation of ARM programs on the ARM platform. ANA is a lightweight ARM instruction interpreter that uses the hardware to do a lot of the work for the read-decode-execute piece of simulation. We compare this method to the two existing methods of full simulation and direct execution that have been traditionally used to achieve this. We demonstrate that despite some setbacks caused by the prefetching and caching behaviors of the ARM, ANA continues to be a very useful tool for prototyping and for increasing simulator performance. Finally, we identify the important role that ANA can play in our current efforts to virtualize the ARM.<br>by Calvin On.<br>M.Eng.

The purpose of this thesis was to find an optimal way to construct and control a product that could help those who suffer from muscle weakness or a muscle sickness. The device was made out of two major parts (upper arm and lower arm) which were connected through a motorized joint. The focus was on finding a satisfying construction that could handle the forces and with the help of sensors measure movement of the users arm relative to the construction and then control it using that information. The device needed to be fast and reliable and react to small movements to be as comfortable for the user as possible.  The result was a construction controlled by measuring the forces from the user’s movement with the use of force sensors placed at the wrist. The construction managed to follow the users’ arm, fast and in a satisfactory way.<br>Tanken med detta arbete var att hitta ett optimalt sätt att konstruera en produkt som skulle hjälpa de som lider av muskel -svaghet och -sjukdom. Produkten skulle bestå av två större delar (överarmen och underarmen) som var sammanlänkade med en motoriserad led. Fokusen låg på att hitta en tillfredställande konstruktion som kunde hantera krafterna och med hjälp av sensorer kunna mäta avståndet och rörelsen på användarens arm och förflytta konstruktionen utifrån det. Produkten behövde vara snabb, pålitlig och reagera på små rörelser för att vara så bekväm för användaren som möjligt. Resultatet blev en konstruktion som styrs genom att mäta tryckkraften, när användaren flyttar armen, med hjälp av trycksensorer som placeras vid handleden. Konstruktionen lyckades följa användarens arm, snabbt och på ett tillfredställande sätt.

This project focuses on balancing a drinking glass, to be able to transport it without the contents being spilled. It is designed with the aim of replacing a waiter in a restaurant or bar environment, but the technology itself could well be applied on mobile cup holders in cars or boats for instance. The core of the project is to study how and if it is possible to create a platform capable of balancing a drinking glass when exposed to different acceleration forces. This report describes one way of constructing this cup holder, with explanations of how the hardware has been designed and put together as well as how the software was written to make the components work together. The objective was to tilt the platform so that the acceleration resultant always was aligned with the z-axis of the sensor. The balancing part was divided in two separate systems, each controlling one rotation around two perpendicular axes. The rotation was controlled by two DCmotors, which counter forces that occur when the prototype is tilted and accelerated in different directions. To measure these movements, an IMU sensor containing both an accelerometer and a gyroscope was used. This sensor was placed in the center of rotation to increase sensor accuracy. To relate the input signal from the sensor to the output signal to the motors, a PIDcontroller was used. It was studied whether mathematical modelling or experimental testing provided the best method to determine the parameter values for this PID-controller. To test the performance, data about acceleration and relative angle to the acceleration resultant was gathered. This showed how high accelerations the system could handle, to evaluate if the system could be used in a restaurant or a bar environment. It also showed how much the platform was tilting in relation to the acceleration resultant, which determines if the liquid would stay in the glass. Additionally, a survey was created to gather opinions regarding robots in a restaurant or bar environment. The implementation is deemed possible and the survey showed that there is a great interest for this product. A clear majority answered that they would be attracted to a restaurant or a bar with robotic waiters. The study of three different ways to apply the derivative part of the PIDcontroller concludes that the use of the gyroscope was the best for this application, despite its inability to react on acceleration from linear motion. Experimental testing proved most time efficient to determine the parameter values for the PID-controller, but the non-linearized mathematical model of the system that is presented could well serve as a foundation to further improve this controller.<br>Detta projekt fokuserar på balanseringen av ett dryckesglas, för att kunna transportera detta utan att innehållet spills ut. Designen är främst tänkt för att ersätta en servitör i restaurangverksamhet, men teknologin kan väl appliceras till mobila dryckeshållare i exempelvis bilar och båtar. Kärnan i projektet är att studera hur och om det är möjligt att skapa en plattform som klarar av att balansera ett dryckesglas när den utsätts för olika accelerationskrafter. Denna rapport beskriver ett sätt att gå tillväga för att konstruera denna dryckeshållare, med förklaringar om hur hårdvaran har designats och satts ihop samt hur mjukvaran fått komponenterna att fungera tillsammans. Målet var att vrida plattformen så att accelerationsresultanten alltid var riktad längs sensorns z-axel. Balanseringen delades upp i två separata system som reglerar varsin rotation kring två vinkelräta axlar. Rotationen drivs av två DC-motorer, som motverkar de krafter som uppstår när testplattformen vinklas och accelererar i olika riktningar. För att mäta dessa röresler användes en IMU-sensor som innehöll både accelerometer och gyroskop. Sensorn var placerad i rotationscentrum för att öka precisionen i mätningarna. För att relatera insignalen från sensorn till utsignalen till motorerna användes en PID-kontroller. Det undersöktes om matematisk modellering eller experimentell testning gav den bästa metoden att bestämma parametrarvärdena till denna PID-kontroller. För att testa prestationsförmågan samlades accelerationsdata samt data om den relativa vinkeln till accelerationsresultanten. Detta visade hur höga accelerationer som systemet klarade att hantera, för att utvärdera om systemet kunde användas i en restaruang- eller barmiljö. Det visade även hur mycket plattformen lutade relativt accelerationsresultanten, vilket avgör om vätskan stannar i glaset. Till detta gjordes också en undersökning för att samla in åsikter om robotar i restaurang- eller barmiljö. Implementationen av denna robot bedöms möjlig och det finns ett intresse för en sådan produkt. En klar majoritet av de tillfrågade svarade att de skulle vara lockade till en restaurang eller bar med robotservitörer. Vid undersökningen av tre olika sätt att applicera den deriverande delen i PID-kontrollern drogs slutsatsen att användadet av gyroskopet var det som fungerade bäst i tillämpningen, trots att den inte kan ta hänsyn till acceleration från rätlinjig rörelse. Experimentell testning visade sig vara mest tidseffektivt för ta fram parametervärdena till PID-kontrollern, men den presenterade icke-lineariserade matematiska modellen av systemet kan väl utgöra en grund för att förbättra denna kontroller.

This paper looks at all aspects of developing a robotic arm and hand that consists of five fingers which is able to imitate human movements. The imitation ability, accuracy and factors affecting both points are studied. A project like this requires the interplay of various electrical components to achieve the desired results.The prototype constructed measured the controller’s movements of the fingers with the help of flex sensors. The movements in the elbow and wrist however were measured with the help of potentiometers. The flex sensors and potentiometers were connected to an Arduino Mega which then sent the values with the help of a transmitter. The robotic arm consists of an Arduino Uno, seven servomotors and a receiver that reads the messages sent from the transmitter. All values were converted into degrees that rotated the motor axles accordingly. The prototype produced positive results, showing that it was able to copy all movements done by the controller. Tests were conducted to study the accuracy and imitationability. The conclusion was that the factors affecting imitation and accuracy were mostly connected to the weight of the robot and the design of the hand.<br>Denna uppsats behandlar olika aspekter i utvecklingen av en robotarm vars gripdon är en hand med fem fingrar, med syfte att kunna imitera mänskliga rörelser. Imitationsförmågan, noggrannheten samt vilka faktorer som påverkar dessa studeras. För att uppnå ett önskvärt resultat har det krävts styrning och samverkan mellan olika elektroniska komponenter. I prototypen som presenteras mättes fingrarnas rörelsemed hjälp av flexsensorer samt rörelsen i armbåge och handleden med hjälp av vridpotentiometrar. Flexsensorerna och potentiometrarna var anslutna till en Arduino Mega vars värden skickades med hjälp av en sändare. Elektronikkomponenterna som användes i robotarmen var en ArduinoUno, sju servomotorer och en mottagare, vars funktion var att läsa av meddelanden som skickades från sändaren. Alla värden omvandlades till grader och motoraxlarna roterade i enlighet med dessa. Prototypen uppnådde ett önskvärt betteende då roboten hade förmågan att imitera alla rörelser som utfördes av styrenheten. Noggrannheten och imitationsförmågan undersöktes med olika tester. De mest betydelsefulla faktorer som påverkade imitationen och noggrannheten av prototypen var kopplade till vikten av roboten och designen av handen, enligt slutsatserna som har dragits.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.<br>Includes bibliographical references (leaf 24).<br>Studying biological systems has given robotics researchers valuable insight into designing complex systems. This thesis explores one such application of a biomimetic robotic system designed around a human arm. The design of an anthropomorphic arm, an arm that is similar to that of a human's, requires deep insight into the kinematics and physiology of the biological system. Investigated here is the design and completion of an arm with 7 degrees of freedom and human-like range of motion in each joint. The comparison of actuation schemes and the determination of proper kinematics enable the arm to be built at a low cost while maintaining high performance and similarity to the biological analog. Complex parts are built by dividing structures into interlocking 2d shapes that can easily be cut out using a waterjet and then welded together with high reliability. The resulting arm will become part of a bionic system when combined with an existing bionic hand platform that is being developed in the Intelligent Machines Laboratory at MIT. With a well thought out modular design, the system will be used as a test bed for future research involving data simplification and neurological control. The completion of the anthropomorphic arm reveals that is indeed feasible to use simple DC motors and quick fabrication techniques. The final result is a reliable, modularized, and anthropomorphic arm.<br>by Adam Paul Leeb.<br>S.B.

In this thesis a working control system for a 7 degrees of freedom hand prosthesis model controlled by electromyographic and accelerometer signals has been developed.The complete system consists of a wireless EMG and accelerometer measurement system, two National Instruments data acquisition modules, a desktop computer, a Lego Mindstorms NXT brick and a hand model with 7 motorized degrees of freedom.The controller is based on pattern recognition and signal classification.Several different EMG features for this purpose are presented and implemented.Two different linear classifiers were used and their performance studied.The LabVIEW software platform was used for both the computer and the NXT.The developed software has a modular design, facilitating future development and extension.Its design and implementation are presented and discussed.

Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>23<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 69-71).<br>Traditionally, robot grasping has been approached in two separate phases: first, finding contact positions that yield optimal grasps and, then, moving the robot hand to these positions. This approach works well when the object's location is known exactly and the robot's control is perfect. However, in the presence of uncertainty, this approach often leads to failure, usually because the robot's gripper contacts the object and causes the object to move away from the grasp. To obtain reliable grasping in the presence of uncertainty, the robot needs to anticipate the possible motions of the object during grasping. Our approach is to compute a policy that specifies the robot's motions over a range of joint states of the object and gripper, taking into account the expected motion of the object when pushed by the gripper. We use methods from continuous-state reinforcement-learning to solve for these policies. We test our approach on the problem of whole-arm grasping for a PR2, where one or both arms, as well as the torso can all serve to create contacts.<br>by Ariel Anders.<br>S.M.