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O principal propósito deste trabalho é desenvolver e caracterizar o veículo robótico ℏelvis III, para ser usado no desenvolvimento de pesquisas na área de controle e navegação de robôs móveis. O sistema de propulsão foi caracterizado para determinar a velocidade real do veículo em quatro tipos diferentes de terrenos (Asfalto, grama, grama-terra e terra). Também foi caracterizado o sistema de esterçamento mediante o modelo cinemático da bicicleta, onde se obteve a relação entre a posição do servo motor encarregado do esterçamento do veículo e o valor do ângulo de esterçamento de uma bicicleta. Foram determinados os valores dos erros CEP (Circular Error Probability) e SEP (Spherical Error Probability) do GPS (Global Positioning System) embarcado no veículo mediante dois testes: um em São Carlos – SP (Brasil) e outro em Villavicencio – Meta (Colômbia). Nesses testes foi caracterizada a IMU (Inertial Measurement Unit) embarcada no veículo, além de verificado o efeito da luz solar no funcionamento do sensor tipo LIDAR (Laser Imaging Detection and Ranging) embarcado no helvis III. Por último, pode-se definir a dinâmica do veículo à frente, com a determinação seu centro de massa, e é apresentado o comportamento das forças sob as rodas quando o veículo fica parado ou em movimento sobre terrenos que geram uma inclinação em algum dos eixos cartesianos. / The main objective of this work is the development and characterization of a robotic vehicle ℏelvis III in order to use it in the development of researches focused on the fields of mobile robotics control and navigation. Initially the propulsion system was characterized in order to determine the real velocity of vehicle in real conditions (four different kinds of grounds were used). In addition to this, the steering system was also characterized by applying the well-known bicycle kinematic model. During these experimental tests we could find the relation between the position of the servo-motor and the value of steering angle of the bicycle model. The real values of CEP (Circular Error Probability) and SEP (Spherical Error Probability) errors of the vehicle embedded GPS (Global Positioning System) were determined based on two experiments: the first one was carried out in São Carlos – SP (Brazil) and the second one in Villavicencio – Meta (Colombia). During the GPS experiments we could also characterize the vehicle embedded IMU (Inertial Measurement Unit). Then we could observe and measure the effect of solar light on the LIDAR sensor (Laser Imaging Detection and Ranging) performance. Finally, the forward vehicle dynamics is described, with the determination of the center of mass of the vehicle and the observation of the normal forces behavior in the vehicle wheels when it is stopped or moved on an inclined floor.

O principal propósito deste trabalho é desenvolver e caracterizar o veículo robótico ℏelvis III, para ser usado no desenvolvimento de pesquisas na área de controle e navegação de robôs móveis. O sistema de propulsão foi caracterizado para determinar a velocidade real do veículo em quatro tipos diferentes de terrenos (Asfalto, grama, grama-terra e terra). Também foi caracterizado o sistema de esterçamento mediante o modelo cinemático da bicicleta, onde se obteve a relação entre a posição do servo motor encarregado do esterçamento do veículo e o valor do ângulo de esterçamento de uma bicicleta. Foram determinados os valores dos erros CEP (Circular Error Probability) e SEP (Spherical Error Probability) do GPS (Global Positioning System) embarcado no veículo mediante dois testes: um em São Carlos – SP (Brasil) e outro em Villavicencio – Meta (Colômbia). Nesses testes foi caracterizada a IMU (Inertial Measurement Unit) embarcada no veículo, além de verificado o efeito da luz solar no funcionamento do sensor tipo LIDAR (Laser Imaging Detection and Ranging) embarcado no helvis III. Por último, pode-se definir a dinâmica do veículo à frente, com a determinação seu centro de massa, e é apresentado o comportamento das forças sob as rodas quando o veículo fica parado ou em movimento sobre terrenos que geram uma inclinação em algum dos eixos cartesianos. / The main objective of this work is the development and characterization of a robotic vehicle ℏelvis III in order to use it in the development of researches focused on the fields of mobile robotics control and navigation. Initially the propulsion system was characterized in order to determine the real velocity of vehicle in real conditions (four different kinds of grounds were used). In addition to this, the steering system was also characterized by applying the well-known bicycle kinematic model. During these experimental tests we could find the relation between the position of the servo-motor and the value of steering angle of the bicycle model. The real values of CEP (Circular Error Probability) and SEP (Spherical Error Probability) errors of the vehicle embedded GPS (Global Positioning System) were determined based on two experiments: the first one was carried out in São Carlos – SP (Brazil) and the second one in Villavicencio – Meta (Colombia). During the GPS experiments we could also characterize the vehicle embedded IMU (Inertial Measurement Unit). Then we could observe and measure the effect of solar light on the LIDAR sensor (Laser Imaging Detection and Ranging) performance. Finally, the forward vehicle dynamics is described, with the determination of the center of mass of the vehicle and the observation of the normal forces behavior in the vehicle wheels when it is stopped or moved on an inclined floor.

The suspension of the motor vehicle is one of the most important elements of the flexible mounted and inflexible mounted masses of the vehicle bodywork, and most attention is paid to its exploration and improvement. Analysis of models of equivalent oscillation systems of motor vehicles testifies that the evaluation of motor vehicle oscillations and modelling of its motion modes is still very topical and requires further research. Suspension models of motor vehicles offered in publications regard only the influence of road irregularities, and the modernisation of these models is directed towards the improvement of passengers’ comfort. However not much research has been done on the influence of oscillations of flexible mounted and inflexible mounted masses of the bodyworks of vehicles in the process of braking; also there is not much investigation of the post-accident identification of the vehicle’s movement mode corresponding to the deformations of the suspension and the longitudinal pitch of the bodywork. Research of oscillations in the conditions of emergency braking is primarily important for the work in two practical directions: 1) improvement of calculation methods of motor vehicle’s response to external impact in the conditions of real operation; 2) further improvement of research methods on the road, and analysis of fait accompli road accidents related to oscillations in the emergency braking. Methodology defining the oscillations occurring in the braking may be applied... [to full text]

The suspension of the motor vehicle is one of the most important elements of the flexible mounted and inflexible mounted masses of the vehicle bodywork, and most attention is paid to its exploration and improvement. Analysis of models of equivalent oscillation systems of motor vehicles testifies that the evaluation of motor vehicle oscillations and modelling of its motion modes is still very topical and requires further research. Suspension models of motor vehicles offered in publications regard only the influence of road irregularities, and the modernisation of these models is directed towards the improvement of passengers’ comfort. However not much research has been done on the influence of oscillations of flexible mounted and inflexible mounted masses of the bodyworks of vehicles in the process of braking; also there is not much investigation of the post-accident identification of the vehicle’s movement mode corresponding to the deformations of the suspension and the longitudinal pitch of the bodywork. Research of oscillations in the conditions of emergency braking is primarily important for the work in two practical directions: 1) improvement of calculation methods of motor vehicle’s response to external impact in the conditions of real operation; 2) further improvement of research methods on the road, and analysis of fait accompli road accidents related to oscillations in the emergency braking. Methodology defining the oscillations occurring in the braking may be applied... [to full text]