An improved startup mode using clutch coupling for in-wheel electric vehicle drives

By introducing a new type of clutch into the driveline system of an in-wheel drive electric vehicle, a flexible connection has been developed to replace the rigid one between the hub and the motor. The driving motor can realize variable idling, unlike the internal combustion engine, which needs a minimum rotational speed. This paper proposes a new startup method that utilizes the initial kinetic energy of the motor to achieve a smooth and fast acceleration of the wheel speed from zero to the expected motor speed. First, the powertrain system, including the driving motor, the clutch and the vehicle resistance, is modelled. Second, factors influencing the starting current and the jerk level during the starting process are investigated. In consequence, the idle speed can be interpreted as a tunable variable that determines the tradeoff between the torque capacity and the jerk level. Finally, simulation and experiments on a laboratory test rig are performed. The results validate that the proposed variable-idle speed control strategy has a lower jerk level and lower starting current when compared with those using a direct start under the same load condition

Research on torque compensation with optimal pedal throttle for direct-drive electric vehicle start-up

Originalna kruta veza između motora i glavine zamijenjena je fleksibilnom uporabom spojke za povezivanje pogonskog i gonjenog vratila sustava prijenosa. U radu se zatim predstavlja odvojeni proces pokretanja i opterećenja motora na osnovu kojega se analizira shema reguliranja rada motora u praznom hodu. Fokusiranjem na probleme koordinacije povećanog kapaciteta zakretnog momenta i smanjenja trzaja automobila samo regulacijom rada motora u praznom hodu, predlaže se poboljšano rješenje kompenzacije zakretnog momenta podešavanjem napona rotora dok se spojka aktivira gonjenom stranom. Nadalje, ispituje se i optimizira metoda za označavanje napona zakretnog momenta s ciljem stvaranja balansa između traženog prijenosnog mehanizma zakretnog momenta i jačine trzaja tijekom pokretanja vozila. Konačno, eksperimentima je demonstriran učinkovito poboljšani učinak zakretnog momenta pogonskog motora kod pokretanja vozila u svrhu povećane udobnosti.The original rigid connection between the motor and the hub is replaced with a flexible one using the clutch to connect the driving and driven sides of the driveline system. Then the paper proposes a separable process of motor start-up and load operation, based on which the scheme of idle speed control is studied. Focusing on the contradiction between the extended torque capacity and the reduced vehicle jerk merely by tuning the idle speeds, an improved solution is proposed for toque compensation by throttle adjustment during the clutch engagement. Furthermore, the method for tracking the armature voltage of the driving motor is investigated and optimized, aiming at the balance between the demanded transmitted torque and the jerk level during the starting process. Finally, effectively enhanced torque capacity of the driving motor for the vehicle start-up on the premise of the improved comfort level has been demonstrated by experiments

Autonomous Tracked Robots. History, Modelling, Localization, and Motion Control

[ES] Uno de los campos de aplicación más significativos de la robótica móvil consiste en robots capaces de operar en condiciones exteriores sobre terrenos no preparados (robots planetarios, robots en agricultura, robot en operaciones de búsqueda y rescate, robots militares, etc.). Sin embargo, conseguir que los robots se muevan de forma eficiente y precisa en este tipo de entornos no es una tarea sencilla. Un primer aspecto crítico es el sistema de locomoción. En este caso, las orugas constituyen una alternativa sólida a otro tipo de sistemas y desde principios del siglo XX han demostrado sus bondades en vehículos tripulados. En este artículo se motiva y se demuestra mediante pruebas reales la idoneidad de este tipo de locomoción para robots móviles en terrenos no preparados. Es importante remarcar que este artículo pretende ser un resumen extendido del libro recientemente publicado por los autores “Autonomous Tracked Robots in Planar Off-Road Conditions” (González et al., 2014), y, por lo tanto, no pretende ser una contribución original. Inicialmente se presenta una perspectiva histórica de los vehículos y los robots con orugas. Posteriormente se discuten los aspectos de modelado con especial mención al fenomeno del deslizamiento. A continuación, se analizan varias estrategias de localización, en particular, la odometria visual. También se analiza el aspecto del control de navegación, para ello se analizan varias estrategias con compensación del deslizamiento. Finalmente se expresan las conclusiones del trabajo en base a la experiencia de los autores en este campo.[EN] One of the most significant research field in mobile robotics deals with robots operating in off-road conditions (planetary rovers, agriculture robots, search and rescue operations, military robots, etc.). However, obtaining a successful result is not an easy task. One primary point is the locomotion system. In this case, tracks constitute a well-known approach and since the beginning of the 20th century this locomotion system has demonstrated remarkable results in manned vehicles. This article motivates and shows through physical experiments the goodness of tracked mobile robots in off-road conditions. Firstly, a historical perspective of tracked vehicles and tracked robots is addressed. Then, the main modelling aspects are introduced, in particular, the slip phenomenon. After that, several localization techniques are discussed with especial mention to visual odometry. The motion control aspect is also of primal importance. In this regard, several slip-compensation control strategies are analysed. Finally, the authors background obtained in this field is expounded.Este trabajo ha sido realizado en el marco del proyecto Controlcrop PIO-TEP-6174, financiado por la Consejería de Economía, Innovación y Ciencia de la Junta de Andalucía (España).González, R.; Rodríguez, F.; Guzmán, JL. (2015). Robots Móviles con Orugas Historia, Modelado, Localización y Control. Revista Iberoamericana de Automática e Informática industrial. 12(1):3-12. https://doi.org/10.1016/j.riai.2014.11.001OJS312121Angelova, A., Matthies, L., Helmick, D., & Perona, P. (2007). Learning and prediction of slip from visual information. Journal of Field Robotics, 24(3), 205-231. doi:10.1002/rob.20179Benoit, O., Gotteland, P., & Quibel, A. (2003). Prediction of trafficability for tracked vehicle on broken soil: real size tests. 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