Designing Omni-Directional Mobile Robot Platform for Research

Machines, as a key workforce in manufacturing, mining, construction, are essential for industry, and socially. However, existing mobile robots’ designs do not provide enough mobility and maneuverability. This is one of the major factors that requires an improved design of mobile robot platform. This thesis is focused on designing an improved Omni-directional robot platform that has good mobility and maneuverability. To realize these conditions, a lot of criteria and constraints need to be considered in the design process. The conceptual design flows of this mobile robot are to satisfy the need of a mobile robot platform, establish Omni-directional mobile robot specifications followed by concept generation and concept selection. A full decomposition of Omni-directional mobile robot was done. This was followed by building a morphology chart to gather several ideas for those sub-functions of mobile robot. Combination of different types of sub-functions will generate several new Omni-directional mobile robot concepts. The concepts were drafted by using Three-dimensional (3-D) Computer Aided Designing SOLIDWORKS software. After concept generation, the concepts were evaluated by using weighted decision matrix method. The best concept was generated from 3-D design to get 2-D technical drawing and kinematics analysis. These analysis and results of the robot performance are presented in this thesi

Control Passive Mobile Robots for Object Transportation - Braking Torque Analysis and Motion Control -

2007 IEEE International Conference on Robotics and Automation, Roma, Italy, 10-14 April 2007 / Proceedings of 2007 IEEE International Conference on Robotics and Automatio

Design and Control of Robotic Systems for Lower Limb Stroke Rehabilitation

Lower extremity stroke rehabilitation exhausts considerable health care resources, is labor intensive, and provides mostly qualitative metrics of patient recovery. To overcome these issues, robots can assist patients in physically manipulating their affected limb and measure the output motion. The robots that have been currently designed, however, provide assistance over a limited set of training motions, are not portable for in-home and in-clinic use, have high cost and may not provide sufficient safety or performance. This thesis proposes the idea of incorporating a mobile drive base into lower extremity rehabilitation robots to create a portable, inherently safe system that provides assistance over a wide range of training motions. A set of rehabilitative motion tasks were established and a six-degree-of-freedom (DOF) motion and force-sensing system was designed to meet high-power, large workspace, and affordability requirements. An admittance controller was implemented, and the feasibility of using this portable, low-cost system for movement assistance was shown through tests on a healthy individual. An improved version of the robot was then developed that added torque sensing and known joint elasticity for use in future clinical testing with a flexible-joint impedance controller

Designing Omni-Directional Mobile Robot Platform for Research

Machines, as a key workforce in manufacturing, mining, construction, are essential for industry, and socially. However, existing mobile robots’ designs do not provide enough mobility and maneuverability. This is one of the major factors that requires an improved design of mobile robot platform. This thesis is focused on designing an improved Omni-directional robot platform that has good mobility and maneuverability. To realize these conditions, a lot of criteria and constraints need to be considered in the design process. The conceptual design flows of this mobile robot are to satisfy the need of a mobile robot platform, establish Omni-directional mobile robot specifications followed by concept generation and concept selection. A full decomposition of Omni-directional mobile robot was done. This was followed by building a morphology chart to gather several ideas for those sub-functions of mobile robot. Combination of different types of sub-functions will generate several new Omni-directional mobile robot concepts. The concepts were drafted by using Three-dimensional (3-D) Computer Aided Designing SOLIDWORKS software. After concept generation, the concepts were evaluated by using weighted decision matrix method. The best concept was generated from 3-D design to get 2-D technical drawing and kinematics analysis. These analysis and results of the robot performance are presented in this thesi

Front and Back Movement Analysis of a Triangle-Structured Three-Wheeled Omnidirectional Mobile Robot by Varying the Angles between Two Selected Wheels

Omnidirectional robots can move in all directions without steering their wheels and it can rotate clockwise and counterclockwise with reference to their axis. In this paper, we focused only on front and back movement, to analyse the square- and triangle-structured omnidirectional robot movements. An omnidirectional mobile robot shows different performances with the different number of wheels and the omnidirectional mobile robot’s chassis design. Research is going on in this field to improve the accurate movement capability of omnidirectional mobile robots. This paper presents a design of a unique device of Angle Variable Chassis (AVC) for linear movement analysis of a three-wheeled omnidirectional mobile robot (TWOMR), at various angles (θ) between the wheels. Basic mobility algorithm is developed by varying the angles between the two selected omnidirectional wheels in TWOMR. The experiment is carried out by varying the angles (θ = 30°, 45°, 60°, 90°, and 120°) between the two selected omniwheels and analysing the movement of TWOMR in forward direction and reverse direction on a smooth cement surface. Respectively, it is compared to itself for various angles (θ), to get its advantages and weaknesses. The conclusion of the paper provides effective movement of TWOMR at a particular angle (θ) and also the application of TWOMR in different situations

DESIGN AND DEVELOPMENT OF AN OMNIDIRECTIONAL MOBILE BASE FOR A SOCIAL ROBOT

Master'sMASTER OF ENGINEERIN

Haptic-Enabled Handheld Mobile Robots: Design and Analysis

The Cellulo robots are small tangible robots that are designed to represent virtual interactive point-like objects that reside on a plane within carefully designed learning activities. In the context of these activities, our robots not only display autonomous motion and act as tangible interfaces, but are also usable as haptic devices in order to exploit, for instance, kinesthetic learning. In this article, we present the design and analysis of the haptic interaction module of the Cellulo robots. We first detail our hardware and controller design that is low-cost and versatile. Then, we describe the task-based experimental procedure to evaluate the robot's haptic abilities. We show that our robot is usable in most of the tested tasks and extract perceptive and manipulative guidelines for the design of haptic elements to be integrated in future learning activities. We conclude with limitations of the system and future work

직진 주행 성능 향상을 위한 다중 이동 로봇의 새로운 바퀴 배치

학위논문 (석사)-- 서울대학교 대학원 : 기계항공공학부, 2013. 2. 주종남.다중 이동 로봇은 2차원 구동 평면에서 3자유도를 가지며 어느 방향으로나 회전 및 이동이 자유로운 로봇이다. 본 논문에서는 다중 이동 로봇의 직진 주행 성능을 향상시키기 위해 새로운 바퀴 배치를 가지는 다중 이동 로봇을 제안한다. 새롭게 제안된 다중 이동 로봇은 바퀴의 회전방향이 로봇의 질량중심에서 원주방향을 향하는 바퀴 배치를 가지는 기존의 다중 이동 로봇과 달리 바퀴의 회전방향이 로봇의 질량중심을 향하는 바퀴 배치를 가지고 있다. 새롭게 제안된 다중 이동 로봇은 이러한 바퀴 배치로 인하여 직진 주행 시에 로봇의 회전 모멘트가 생성되지 않아 제어가 간단하다. 또한, 3개의 바퀴를 모두 구동시킬 수 있는 장점으로 인해 직진 주행 성능이 뛰어날 뿐만 아니라 기존의 다중 이동 로봇과는 달리 부가적으로 생성되는 저항이 없어 추가적으로 장착해야 할 부품 수도 줄일 수 있다. 제안된 다중 이동 로봇과 기존의 다중 이동 로봇의 직진 주행 성능을 비교하기 위해서 마찰실험을 통하여 다중 이동 로봇이 주행 시에 필연적으로 발생하는 마찰과 미끄러짐을 고려한 동적 모델링을 이끌어 내었다. 이끌어낸 로봇의 동적 모델링을 이용해 두 다중 이동 로봇의 직진 주행을 시뮬레이션을 하였으며 그 결과 새롭게 제안된 다중 이동 로봇의 직진 주행 성능이 1.5배 상향된 것을 확인할 수 있었다. 또한 이를 검증하기 위해 실제 제작된 다중 이동 로봇과 초고속 카메라를 이용해 실제 다중 이동 로봇의 주행과 시뮬레이션 결과를 비교하였다. 그 결과, 마찰실험을 이용하여 이끌어낸 로봇의 동적 모델링이 실제의 다중 이동 로봇의 주행과 일치하는 것을 확인할 수 있었으며 새롭게 제안된 다중 이동 로봇이 기존의 다중 이동 로봇보다 직진 주행 성능이 우수하다는 것을 확인할 수 있었다.국문 초록 ⅰ 목차 ⅲ 그림 목차 ⅴ 표 목차 ⅶ 제 1 장 서론 1 1.1 연구 배경 1 1.2 로봇의 구동력과 미끄러짐 3 1.3 연구 목적 5 제 2 장 바퀴의 동적 모델링 10 2.1 바퀴의 구동력과 미끄러짐 10 2.2 바퀴의 구동방정식 11 2.3 마찰실험 장치 구성 13 2.4 마찰실험 결과 16 제 3 장 로봇의 동적 모델링 17 3.1 기존의 다중 이동 로봇의 동적 모델링 17 3.2 새로운 다중 이동 로봇의 동적 모델링 19 3.3 로봇의 동적 모델링의 시뮬레이션 및 결과 20 제 4 장 검증 24 4.1 검증을 위한 실험 장치 구성 24 4.2 검증 실험 결과 25 제 5 장 결론 29 참고 문헌 31 Abstract 34Maste

Motion Control of Holonomic Wheeled Mobile Robot with Modular Actuation

This thesis proposes a control scheme for a new holonomic wheeled mobile robot. The platform, which is called C3P (Caster 3 wheels Platform), is designed and built by the Automation Lab., University of Heidelberg. The platform has three driven caster wheels, which are used because of their simple construction and easy maintenance. The C3P has modular actuators and sensors configurations. The robot’s actuation scheme produces singularity difficulties for some wheel steering configuration, described as the following: When all wheels yield the same steering angle value, the C3P cannot be actuated in the direction perpendicular to the wheel velocity vector. The C3P has a modular sensing scheme defined by sensing the steering angle and the wheel angular velocity of each caster wheel. This work has four main contributions 1- developing a controller based on an inverse kinematics solution to handle motion commands in the singular configurations; 2- modeling the C3P’s forward dynamics of the C3P for the simulation purpose; 3- developing a motion controller based on an inverse dynamics solution; and 4- comparing the C3P with other standard holonomic WMRs. In order to escape singularity condition, the actuated inverse kinematics solution is developed based on the idea of coupling any two wheel velocities to virtually actuate the steering angular velocity of the third wheel. The solution is termed as the Wheel Coupling Equation (WCE). The C3P velocity controller consists of two parts: a) the WCE regulator to avoid singularities and adjust the steering angles to the desired value, and b) the regular PID controller to maintain the reference robot velocities with respect to the floor frame of coordinates. The solution reaches acceptable performance in the simulation examples and in the practical experiments. However, it generates relatively large displacement errors only during the steering angles adjustment period. The Euler-Lagrangian method is used for obtaining the forward dynamic and the inverse dynamic models. The forward dynamic model consists of two equations of motion: the WTD (Wheel Torque Dynamics) to calculate the wheel angular velocities with respect to the actuated wheels’ torques, and the DSE (Dynamic Steering Estimator) for calculating the steering angles and steering angular velocities corresponding to the angular wheels’ velocities and accelerations. The inverse dynamics solution defines the forces and torques acting on each actuator and joint. The solution is used in the development of the C3P velocity and position controllers. In comparison to the proposed inverse kinematics solution, the inverse dynamics solution yields less displacement errors. Lyapunov stability analysis is carried out to investigate the system stability for different steering angles’ combinations. The steering angles’ values are considered as the disturbances affecting the platform. Finally, a comparison is made between the C3P and three other holonomic wheeled mobile robots configurations. The comparison is based on the simulation results in relation to the following aspects: a) mobility, b) total energy consumed by each robot in a finite interval of time and c) hardware complexity. The C3P platform shows its advantage in the aspects “b” and “c”