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Design of the omnidirectional mobile robot control system based on dSPACE
Published in Jimmy C.M. Kao, Wen-Pei Sung, Civil, Architecture and Environmental Engineering, 2017
Huan-huan Liu, Chang-sheng Ai, Hong-hua Zhao, Xuan Sun
Four-wheel drive (Xin, 2015), also called all wheel drive, refers to the front wheel and the rear wheel have driving force, and the engine output torque is distributed in all the wheels according to the different road conditions. Its main function is to effectively control the vehicle’s lateral movement characteristics and improve the ability of the vehicle. Four-wheel drive relies on the four-wheel independent steering. All wheels can be turned around the same instantaneous center of rotation to achieve different steering radius and even zero turning radius so that it has a high degree of flexibility in the steering wheel. The narrow working space brings great challenge to the mobile robot. Therefore, the control system of the omnidirectional mobile robot adopted the four-wheel drive. The four-wheel drive system is mainly composed of a motor and its driver, driving power supply, and deceleration device. Among them, the servo motor is controlled by pulse and direction.
Four-wheel-drive systems
Published in M.J. Nunney, Light and Heavy Vehicle Technology, 2007
The optional engagement of four-wheel drive, together with a two-speed transfer gearbox, confers superior traction for climbing or descending steep slopes, negotiating really rough ground and travelling in mud or snow. Vehicles of this type are therefore admirably suited for general farming, construction site and light industrial duties.
A mobility model for a tethered skidder
Published in International Journal of Forest Engineering, 2022
Several performance models for untethered four-wheel drive rubber-tired skidders have been developed based upon predicting the traction performance of the individual tire (Wismer and Luth 1973; Ashmore et al. 1987; Brixius 1988) and then integrating that relationship into a vehicle operating model (Iff et al. 1984, Olsen and Gibbons 1983; Phillips 1983; Liljedahl et al. 1996; Duka et al. 2018). We use the individual tire performance model of Ashmore et al. (1987) that exclusively used skidder tires and the flexible stem model for log drag derived by Olsen and Gibbons (1983). Although the flexible stem model developed by Olsen and Gibbons was for delimbed tree stems, we assume the model will also provide reasonable results for full trees based on the work of Hassan and Gustafson (1983) who compared skidding forces of tree stems with whole trees. We extend the four-wheel drive model to a six-wheel drive forwarder with rear tandem axles. To the front of the skidder we attach a tether winch line (Figure 1). The tractive force of the log skidder plus the tension in the winch line are used to maintain static equilibrium. Force diagrams for a rubber-tired skidder skidding rigid logs can be found in Iff et al. (1984) and for skidding flexible tree-lengths in Olsen and Gibbons (1983).
A swarm intelligence-based predictive regenerative braking control strategy for hybrid electric vehicle
Published in Vehicle System Dynamics, 2022
Yuanbo Zhang, Weida Wang, Changle Xiang, Chao Yang, Haonan Peng, Chao Wei
Hierarchical regenerative braking control strategies are proposed for the hybrid braking system [18]. For four-wheel-drive electric vehicles, a feedback hierarchical control strategy is proposed to allocate torque to each wheel [19]. An upper-layer controller is proposed based on sliding mode control theory to calculate total braking torque, and the lower-layer controller is designed considering vehicle motor characteristics when allocating braking torque between wheels. A model predictive control method based regenerative braking control strategies has also been designed [20,21]. Considering the braking intention of the driver and the characteristics of the in-wheel motor, a braking control strategy is proposed [22]. Driver intention is classified under normal braking, and emergency braking, conditions. A model predictive-control-based braking control strategy is proposed to recover braking energy and obey driver intentions under normal braking condition, and a sliding mode control-based braking strategy is designed to guarantee braking safety in emergency braking conditions.
An integrated approach for automated physical architecture generation and multi-criteria evaluation for complex product design
Published in Journal of Engineering Design, 2019
Ruirui Chen, Yusheng Liu, Hongri Fan, Jianjun Zhao, Xiaoping Ye
In a specific product design, the layout category is limited. For example, the layout of an automobile can be roughly divided into three categories according to how power is distributed to the wheels: front-wheel drive, rear-wheel drive and four-wheel drive. Many product layouts are encountered in practice and the locations of components depend on the application of the product. Factors that influence the product layout include cost, complexity, reliability, and weight distribution, which are specified in product requirements. In essence, determining how to layout these components is another multi-criteria decision problem.