Stabilizing control of two-wheeled wheelchair with movable payload using optimized interval type-2 fuzzy logic

The control schemes of a wheelchair having two wheels with movable payload utilizing the concept of a double-link inverted pendulum have been investigated in this article. The proposed wheelchair has been simulated using SimWise 4D software considering the most efficient parameters. These parameters are extracted using the spiral dynamic algorithm while being controlled with interval type-2 fuzzy logic controller (IT2FLC). The robustness and stability of the implemented controller are assessed under different situations including standing upright, forward motion and application of varying directions and magnitudes of outer disturbances to movable (up and down) system payload. It is shown that the two-wheeled wheelchair adopted by the newly introduced controller has achieved a 94% drop in torque for both Link1 and Link2 and more than 98% fall in distance travelled in comparison with fuzzy logic control type-1 (FLCT1) controller employed in an earlier design. The present study has further considered the increased nonlinearity and complexity of the additional moving payload. From the outcome of this study, it is obvious that the proposed IT2FLC-spiral dynamic algorithm demonstrates better performance than FLCT1 to manage the uncertainties and nonlinearities in case of a movable payload two-wheel wheelchair system

Particle swarm optimization and spiral dynamic algorithm-based interval type-2 fuzzy logic control of triple-link inverted pendulum system: A comparative assessment

This paper presents investigations into the development of an interval type-2 fuzzy logic control (IT2FLC) mechanism integrated with particle swarm optimization and spiral dynamic algorithm. The particle swarm optimization and spiral dynamic algorithm are used for enhanced performance of the IT2FLC by finding optimised values for input and output controller gains and parameter values of IT2FLC membership function as comparison purpose in order to identify better solution for the system. A new model of triple-link inverted pendulum on two-wheels system, developed within SimWise 4D software environment and integrated with Matlab/Simulink for control purpose. Several tests comprising system stabilization, disturbance rejection and convergence accuracy of the algorithms are carried out to demonstrate the robustness of the control approach. It is shown that the particle swarm optimization-based control mechanism performs better than the spiral dynamic algorithm-based control in terms of system stability, disturbance rejection and reduce noise. Moreover, the particle swarm optimization-based IT2FLC shows better performance in comparison to previous research. It is envisaged that this system and control algorithm can be very useful for the development of a mobile robot with extended functionality

Abordagem modular aplicada a projeto de pêndulo invertido sobre duas rodas

Orientadores: Eric Fujiwara, Ely Carneiro de PaivaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia MecânicaResumo: Este trabalho propõe a exploração de uma abordagem modular para projeto de pêndulo invertido sobre rodas. Através da escolha apropriada de estruturas de controle, o método permite o desacoplamento de variáveis chave para simplificar o projeto e adicionar benefícios inerentes à modularização. Seguindo os procedimentos propostos, duas plantas virtuais foram simuladas em diferentes contextos e com múltiplos objetivos, como controles de velocidade linear, posição e rastreamento de um alvo. Os resultados demonstraram que o desacoplamento foi efetivo, obedecendo a proposta de baixos níveis de erro para os módulos mais internos com valores máximos menores que 5\% em transientes bruscos. Uma abordagem adaptativa foi proposta e implementada com o objetivo de permitir um desacoplamento mais apropriado entre as variáveis controladas, bem como entre os projetos dos controladores e da planta mecânica. Utilizando controles adaptativos via modelo de referência e via identificação de parâmetros, foi possível realizar o projeto independente de cada malha de controle, com o desempenho de cada componente verificado em simulaçõesAbstract: The following work proposes the evaluation of a modular approach for two-wheeled inverted pendulum design. By properly choosing control loop structures, the method allows for decoupling key variables in order to simplify the project and add inherent benefits from modular systems. By following the proposed approach, two virtual plants were simulated for different contexts with multiple objectives, such as linear velocity control, position control and target following. Results shown effective decoupling, obeying the proposed low error levels for inner modules, with peak values within 5\% for fast transients. An adaptive approach was proposed and implemented aiming to allow for a more appropriate decoupling between the decoupled variables, as well as between the control and the mechanical structure designs. By applying model reference and parameters identification control structures, the independent design of each control loop was made possible. The performance of each component was verified through simulationsMestradoMecatrônicaMestre em Engenharia Mecânica33003017CAPE

Interval type-2 fuzzy logic control optimize by spiral dynamic algorithm for two-wheeled wheelchair

The reconfiguration of the two-wheeled wheelchair system with movable payload has been investigated within the current study towards permitting multi-task operations; through enhanced maneuverability on a flat surface under the circumstances of disturbance rejections during forward and backward motions, as well as motions on the inclined surface for uphill and downhill motions; while having height extensions of the wheelchair’s seat. The research study embarks on three objectives includes developing Interval Type-2 Fuzzy Logic Control (IT2FLC) as the control system, design a Spiral Dynamic Algorithm (SDA) for IT2FLC in stabilizing the designed double-link twowheeled wheelchair system, and optimize the input-output gains and control parameters. The two-wheeled system gives lots of benefits to the user such as less space needed to turn the wheelchair, able to move in the narrow spaces, having eye-to-eye contact with normal people, and can reach stuff on the higher shelve. However, the stability of the twowheeled system will produce high fluctuations due to the uncertainties while stabilizing the system in the upright position. Indirectly, it also caused the long travelled distance and high magnitude of tilt angle and torque. Thus, IT2FLC has been proposed as the compatible control strategy for disturbance rejections to overcome uncertainties for enhanced system stability in the upright position. Basically, IT2FLC uses a Type-2 Fuzzy Set (T2FS) and its membership function (MFs) composed of the lower MFs, upper MFs, and footprint of uncertainty (FOU). This is the reason that IT2FLC possessing the ability to handle cases of nonlinearities and uncertainties that occur in the system. Therefore, any disturbances that give at the back of the seat can be eliminated using the proposed controller, IT2FLC. Additionally, SDA implemented within the control strategy to acquire optimal values of the IT2FLC input-output control gains and parameters of its MFs further accommodated extensive fluctuations of the two-wheeled system; thus, ensuring a safe and comfortable experience among users via shorter traveled distance and lower magnitude of torques following disruptions. The two-wheeled wheelchair is designed using SimWise 4D software to subduing shortcomings of a linearized mathematical model where lengthy equation with various assumptions is required to represent the proposed system; without forgoing its nonlinearity and complexity. Moreover, a 70kg payload was also included to embody an average user, in simulating vertical extensions of the system from 0.11m to 0.25m. The completed model is then integrated with Matlab/Simulink for control design and performance evaluation through visualized simulations. The research has been compared to the previous controllers, Fuzzy Logic Control Type-1 (FLCT1), in gauging improvements and performance superiority. The significance of SDA-IT2FLC as the stability controller within the investigated system has been confirmed through current findings, which outperformed that of its predecessors (IT2FLC and FLCT1). Such results are supported through a significant reduction in traveled distance, tilt, and control torques, following a recorded 5.6% and 33.3% improvements on the stability of the system, to the performance of heuristically-tuned IT2FLC; as well as a 60% and 94% improvements in angular positions on the system, as compared to the FLCT1. Moreover, a 95.4% reduction in torques has been recorded for SDA-IT2FLC, as compared to that of FLCT1. Ultimately, SDAIT2FLC has demonstrated promising outcomes over its predecessors on maintaining the system’s stability in an upright position in terms of faster convergence and a significant reduction in traveled distance, tilt and control torques, proving itself as the robust controller for a double-link two-wheeled wheelchair with movable payload system

Control of a Two-wheeled Machine with Two-directions Handling Mechanism Using PID and PD-FLC Algorithms

This paper presents a novel five degrees of freedom (DOF) two-wheeled robotic machine (TWRM) that delivers solutions for both industrial and service robotic applications by enlarging the vehicle′s workspace and increasing its flexibility. Designing a two-wheeled robot with five degrees of freedom creates a high challenge for the control, therefore the modelling and design of such robot should be precise with a uniform distribution of mass over the robot and the actuators. By employing the Lagrangian modelling approach, the TWRM′s mathematical model is derived and simulated in Matlab/Simulink®. For stabilizing the system′s highly nonlinear model, two control approaches were developed and implemented: proportional-integral-derivative (PID) and fuzzy logic control (FLC) strategies. Considering multiple scenarios with different initial conditions, the proposed control strategies′ performance has been assessed

Development of a Locomotion and Balancing Strategy for Humanoid Robots

The locomotion ability and high mobility are the most distinguished features of humanoid robots. Due to the non-linear dynamics of walking, developing and controlling the locomotion of humanoid robots is a challenging task. In this thesis, we study and develop a walking engine for the humanoid robot, NAO, which is the official robotic platform used in the RoboCup Spl. Aldebaran Robotics, the manufacturing company of NAO provides a walking module that has disadvantages, such as being a black box that does not provide control of the gait as well as the robot walk with a bent knee. The latter disadvantage, makes the gait unnatural, energy inefficient and exert large amounts of torque to the knee joint. Thus creating a walking engine that produces a quality and natural gait is essential for humanoid robots in general and is a factor for succeeding in RoboCup competition. Humanoids robots are required to walk fast to be practical for various life tasks. However, its complex structure makes it prone to falling during fast locomotion. On the same hand, the robots are expected to work in constantly changing environments alongside humans and robots, which increase the chance of collisions. Several human-inspired recovery strategies have been studied and adopted to humanoid robots in order to face unexpected and avoidable perturbations. These strategies include hip, ankle, and stepping, however, the use of the arms as a recovery strategy did not enjoy as much attention. The arms can be employed in different motions for fall prevention. The arm rotation strategy can be employed to control the angular momentum of the body and help to regain balance. In this master\u27s thesis, I developed a detailed study of different ways in which the arms can be used to enhance the balance recovery of the NAO humanoid robot while stationary and during locomotion. I model the robot as a linear inverted pendulum plus a flywheel to account for the angular momentum change at the CoM. I considered the role of the arms in changing the body\u27s moment of inertia which help to prevent the robot from falling or to decrease the falling impact. I propose a control algorithm that integrates the arm rotation strategy with the on-board sensors of the NAO. Additionally, I present a simple method to control the amount of recovery from rotating the arms. I also discuss the limitation of the strategy and how it can have a negative impact if it was misused. I present simulations to evaluate the approach in keeping the robot stable against various disturbance sources. The results show the success of the approach in keeping the NAO stable against various perturbations. Finally,I adopt the arm rotation to stabilize the ball kick, which is a common reason for falling in the soccer humanoid RoboCup competitions

A novel configuration of two-wheeled self-balancing robot

U ovom se istraživanju predstavlja novi projekt samobalansirajućeg robota na dva kotača - two wheeled self-balancing robot (TWSR). Robot je nazvan two-wheeled self-balancing vehicle-pendulum system (TWSVPS). U usporedbi s TWSR, TWSVPS ima jedno klatno (single pendulum (SP)) koje je pasivno spojeno s tijelom robota preko O1 osovine. Teškoća i složenost upravljanja te modeliranje povećani su zbog dodatnog stupnja slobode - degree of freedom (DOF) s klatnom koje rotira oko osovine O1. Zbog jednostavnije analize, TWSVPS se može smatrati vozilom s pokretnim dvostruko obrnutim klatnom. Zbog svoje relativne jednostavnosti, za izvođenje dinamike sustava primijenjena je Lagrangeova dinamička formulacija. Paralelni dvostruki fuzzy upravljač zasnovan na informacijskoj tehnologiji fuzije projektiran je i simuliran u MATLAB-u. Rezultati pokazuju da je metoda izvediva i TWSVPS je izvanredno stabilan u kretanju. Novo razvijena konfiguracija je od velike važnosti u raznim primjenama uključujući samo-balansirajuće robote, kolica za bolesnike na dva kotača, analizu stabilnosti višezglobnih sustava itd.A novel design of the two-wheeled self-balancing robot (TWSR) was presented in this research. The robot was called two-wheeled self-balancing vehicle-pendulum system (TWSVPS). Compared with TWSR, the TWSVPS has a single pendulum (SP), which was passively jointed to the robot body through the O1 axis. The difficulty and complexity of control and modelling were increased due to the additional degree of freedom (DOF) which was offered by the SP rotated around the O1 axis. To simplify the analysis, the TWSVPS can be considered to be the mobile double inverted pendulum. Lagrangian dynamic formulation is used to derive the system dynamics due to its relative simplicity. The parallel double fuzzy controller based on information fusion technology was designed and simulated in MATLAB. The results show that the method is feasible and TWSVPS has excellent moving stability. The new developed configuration is of great importance in various applications including self-balance robots, wheelchairs on two wheels, stability analysis of multi links system etc