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This letter presents a novel planning and control approach for autonomous excavation that is independent of the soil composition and goes beyond a single dig. In contrast to the existing work, which is mostly based on position trajectories for the bucket motion, we define a single dig cycle directly by an end-effector force–torque trajectory. This trajectory applied to different types of soil, resulting...
The train brake system is a complex pneumatic device whose performance and reliability are relatively important. When the train is beging braked, the coupler force caused by the inherent delays in pneumatic airbrakes, commonly used in freight trains, becomes relatively large. The problem is even severe for long freight trains where the delayed response involves heavy longitudinal forces between vehicles...
This paper presents a ironless actuator with two degrees of freedom (2-DoF), which generates a magnetic levitation and propulsion force. It is characterized by a very simple compact construction with a freely accessible mover from above. As a result, it provides a cost-effective solution for vacuum compatible high precision magnetically levitated planar systems. Two possible topology based on this...
Modeling helps explain the fundamental physics hidden behind experimental data. In the case of material modeling, running one simulation rarely results in output that reproduces the experimental data. Often one or more of the force field parameters are not precisely known and must be optimized for the output to match that of the experiment. Since the simulations require high performance computing...
This paper combines coverage control, random-walk and artificial potential method to deploy multi-copter type Unmanned Aerial Vehicles (UAVs). With the coverage control, it is able to deploy agents in the coverage area with arbitrary distribution based on the purpose of control. However, when initial position of agents concentrates on one location, it could be fallen into the local optimal solution...
Surface registration is an inevitable step for solving the correspondence problem in statistical shape modeling and useful for automatic 3D segmentation of objects of a certain shape. Common techniques for a pairwise surface registration rely either on a point-based or a mesh-based representation of the source (moving) and the target (fixed) surface. Iterative closest point (ICP) algorithms operate...
This paper describes the optimization and the performance evaluation of a Permanent Magnet spring. A dedicated semi-analytical model of the device is developed allowing for fast and accurate evaluation of the force vs. displacement characteristic of an arbitrary arrangement of coaxial ring-shaped PMs. This model is used to define the cost function to find the optimal PMs configuration which realizes...
This paper presents the comparative study and optimal design of a transverse flux linear machine with different PM configurations, viz. surface-mounted and consequent-pole, in which the consequent-pole version is firstly proposed. Firstly, the effect of variation of the main design parameters on both topologies are studied. Then, the multi-objective optimization method based on genetic algorithm combined...
As a kind of green energy, the wave energy exhibits high energy density, abundant global reserves, extensive application and high predictability. To this application, the direct driven linear motors already become strong candidates in recent year due to the motion feature of waves, therefore a kind PM-assisted reluctance synchronous linear generator (PMRSLG) is proposed in this paper. Based on FEA,...
Parameter optimization of active suspension in in-wheel motor driven electric vehicle using genetic algorithm (GA) is presented. In such vehicles, placing the motors in the wheel results in an increase in the unsprung mass, which greatly deteriorates the suspension ride comfort performance and road holding ability. Structures with suspended shaftless direct-drive motors have the potential to improve...
In this paper, a new modular linear flux-switching permanent magnet machine is presented. The operation principle is illustrated in detail. The electromagnetic performance analysis of the machine is carried out by the finite-element method. To investigate the influence of the mover pole pitch to stator pole pitch ratio on the new modular machine, the proposed machines with three different ratios are...
This paper introduces an inductor magnetic lead screw (IMLS) for simplify the structure of magnetic lead screw (MLS). The IMLS is formed on the basis of reluctance MLS with toroidal windings on both sides of the screw. The windings are assigned by dc current of reserved direction to produce magnetic flux through the air gap. The degree of freedom of the nut and screw is limited to avoid the brush...
A novel parametric model of the stiifened shell is developed by Python language with Abaqus in this paper. As an effective analysis method in the optimal design, explicit finite element method (FEM) is used to design and optimize the skin thickness and stiffener size of Stiffened Shells. The optimization objectives and constraints are mainly the minimum mass subject to the structural performance and...
In this study, rivet optimization is analyzed for a channel section of a fuselage frame. Rivets are captured by using beam elements in ANSYS Workbench. In order to optimize locations of rivets, basic rivet group on frame is analyzed by using given output loads (forces and moment). Based on this analysis, hand calculation was conducted then Workbench optimization option in ANSYS is used to find out...
In this paper, we discuss rolling regulations of hot strip mills and use mechanism models to build operation optimization problem (OOP). However, the OOP takes on the character of highly nonlinearity and coupling. It is difficult to solve the global optimal solution of OOP. To overcome this difficulty, we present the method based on GP Modeling. Because (GP) problem can be transformed into a convex...
The four-wheel-independent-drive electric vehicle has potential superiority in improving operational efficiency and enhancing vehicle motion control performance by allocating different torques to four wheels. To achieve the energy optimization and to ensure the driving stability, a multi-objective optimal control allocation law is proposed, which composed of two steps of optimization. A pre-allocation...
The dual-drive H gantry is widely used in many industrial processes that require high precision Cartesian motion. The conventional rigid-link version suffers breaking down of joints if any de-synchronization between the two carriages occurs. To prevent above potential risk, a novel biaxial gantry with flexure-links is designed to allow a small rotation angle of the cross-arm. Nevertheless, the chattering...
Cooperative usage of multiple UAVs as a swarm can deliver high-quality surveillance performance. However, the communication capabilities within the UAV swarm must be maintained for local data propagation to swarm members in favor of achieving an efficient global behavior. In this paper, we address the problem of optimizing two adversary criteria for such a UAV swarm: (a) maximizing the area coverage,...
We investigate the problem of distributed source seeking with velocity actuated and force actuated vehicles by developing distributed Kiefer-Wolfowitz algorithm. First, based on stochastic approximation algorithm with expanding truncations, we present the distributed Kiefer-Wolfowitz algorithm, in which two noisy observations of each agent's objective function is used to estimate its gradient and...
I Ching (Chinese characters: $$$) philosophy, stemming from ancient Chinese culture, is Chinese view of empiricism, world outlook and dialectics. Over thousands of years of evolving and interpretation, its cosmological wisdom has broad and profound influences not only on Chinese prevailing philosophy, but also on westerns. I Ching concentrates on the virtue of being moderate and appropriate, representing...
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