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Dynamics Modelling and Adaptive Identification: Towards Improved Human-Robot Interaction in Collaborative Systems
Full text linkThis article presents a novel approach to enhancing human-robot collaboration and safety through advanced dynamic modelling and adaptive identification techniques. We introduce a comprehensive methodology that integrates motion trajectory design with real-time torque detection, addressing the critical limitations of conventional systems that rely on costly joint torque sensors. By simultaneously identifying friction forces in an integrated joint and a simplified two-bar mechanism, our approach leverages existing kinematic and dynamic models to achieve precise dynamic parameter identification. The proposed method significantly advances the fields of drag-teaching and collision detection by eliminating the need for force sensors, thus making it more feasible for mass-produced robotic systems. Our findings demonstrate that accurate dynamic modelling is essential for effective zero-force control, particularly in high-speed drag-teaching scenarios, where inertia and friction present substantial challenges. Experimental validation confirms the efficacy of our dynamic feed-forward controller design and the adaptability of drag-teaching parameters, leading to improved operational flexibility and safety in collaborative environments. This research contributes a critical framework for future developments in intelligent robotic systems, providing a robust basis for integrating advanced human-robot interactions in industrial applications
Multi-Growth Period Tomato Fruit Detection Using Improved Yolov5
Full text linkAbstract: In agricultural mechanized production, in order to ensure the efficiency of hand-eye cooperative operation of tomato picking robot, the recognition accuracy and speed of multi-growth period tomato fruit is an important basis. Therefore, in order to improve the recognition speed of multi-growth period tomato fruit while ensuring or improving the accuracy, this paper improves the Yolov5s model by adding the architecture of the lightweight mobilenetv3 model. Firstly, the deep separable convolution is replaced in the backbone network of Yolov5s, which reduces the amount of convolution operation. Secondly, the linear bottleneck inverse residual structure is fused to obtain more features in high-dimensional space and perform convolution operation in low-dimensional space. Third, the attention mechanism is inserted into the last layer of the network to highlight features and improve accuracy. The research results show that the recognition accuracy of the improved Yolov5 model remains above 98%, the CPU recognition speed is 0.88f·s-1 faster than Yolov5s, and the GPU recognition speed is 90 frames per second faster than Yolov5s. Finally, a set of the recognition software system of multi-growth period tomato fruit is designed and developed by using RealSense D435i depth camera and PYQT. The software system further verifies the feasibility of the improved Yolov5 model, and lays a foundation for the visual software design of agricultural picking robot picking recognition
Comprehensive Economic Benefits Evaluation Model of Greenhouse Photovoltaic
Full text linkAbstract: Photovoltaic integrated greenhouse has become an important form of deep coupling between new energy power generation and facility agriculture. Greenhouse photovoltaic power generation will affect the light environment, thermal environment, and water environment of facility agriculture. The precise coupling modeling method of greenhouse photovoltaics and loads is to carry out the basis for the calculation of comprehensive economic benefits of greenhouse photovoltaics. This paper studies the deep coupling modeling method of greenhouse photovoltaic and greenhouse load, and accurately calculates the changes in the light environment, thermal environment, and water environment regulation load of facility agriculture caused by the laying of greenhouse photovoltaics. Firstly, the greenhouse photovoltaic power generation model and the environmental regulation load model of facility agriculture are established; secondly, the coupling relationship between greenhouse photovoltaic power generation and facility agricultural load is described, and on this basis, the comprehensive economic benefits evaluation model of photovoltaic power generation is proposed. The 10kV medium-voltage distribution network and facility agricultural greenhouse that exist in the northern region are used as the research objects. It verifies the validity of the photovoltaic comprehensive economic benefits evaluation model proposed in this paper
Surface Coating of Cyclotetramethylenetetranitramine (HMX) Particles and Its Property Investigation
Full text linkTo improve the safety of cyclotetramethylenetetranitramine (HMX) particles, the polymer thermoplastic polyurethane elastomer (TPU) and nitrocellulose (NC) were introduced to coat HMX powder by water-solution suspension method and internal solution method, respectively. Scanning electron microscope (SEM) and X-ray photo-electron spectrometry (XPS) were employed to characterize the HMX samples and the role of NC and TPU in the coating processes were discussed. The impact sensitivity, friction sensitivity, and the thermal decomposition of coated HMX particles were investigated, and compared to the unprocessed ones. The results indicate that both TPU and NC can improve the wetting ability of the coating materials on HMX surface and reinforce the connection between HMX and the coating materials. The impact sensitivity and friction sensitivity of HMX samples decrease obviously after they have been surface coated; the drop height (H50) is increased from 35.24 cm to 50.08 cm, and the friction probability is reduced from 93.2 % to 58.3%. The activation energy (Ea) and the self-ignition temperature increase by 10.46 KJ·mol-1 and 1.8, respectively
Development of a Low Cost Eco-Friendly Minimum Quantity Lubrication System for Machining Processes
Full text linkRecently all environmental worries are calling for reducing the usage of fluids in machining operations. One of the promising solutions that appeared lately is minimum quantity lubrication (MQL). This research aimed to develop an eco-friendly cooling system for a lathe machine and assess its performance. After considering the customer needs, the needs were translated into engineering specifications in the conceptual design phase, and then the quality function deployment was developed. Three concepts were generated and evaluated considering the selection criteria, and a final concept was selected using the decision matrix method. Following this, a detailed design and fabrication of the sub-systems such as the oil tank and a structure accommodate all the components. The developed system was tested on six different workpiece samples to compare the MQL system with the conventional one. In general, the MQL system resulted in lower surface roughness values as well as lower tool wear
Coordinated Movement of Multiple Robots in Outdoor Environment with Obstacles Pages
Full text linkThis article mainly focuses on the proposal of the program that coordinates the movement of multiple robots in outdoor environment. The emphasis of the proposed algorithm is on collision free movement. Simulation with four robots that are controlled in an environment with obstacles is the result of these experiments. The formation of robots consists of a leader and three following robots, which are trying to copy leader¢‚¬„¢s movement. Robots use GPS, laser rangefinder, as well as bumpers sensors for the environment scanning. GPS is used as positioning sensor and other sensors are used for reactive navigation. Besides that, simulation uses virtual reality from Microsoft Robotics Studio 4 (MRS). In addition, programming language used for this simulation is called Visual Programming Language. Advantage of MRS usage is that the final code can be simply transferred into real robots
An Evolutionary Approach to Tuning a Multi-Agent System for Autonomous Adaptive Control of a Flapping-Wing Micro Air Vehicle
Full text linkBiomimetic flapping wing vehicles have attracted recent interest because of their numerous potential military and civilian applications. In this paper, we describe an evolutionary approach to tuning a Multi-Agent System for autonomous adaptive control of a Flapping-Wing Micro Air Vehicle. The wings of the vehicle are controlled by a split cycle oscillator, which combined with non-linearities and differences between each vehicle, brings significant challenge for selecting the proper parameters for the control system. Adopting a Neo-Darwinistic evolutionary approach, where solutions are evolved in a similar manner as in nature, allows us to precisely learn control parameters for each vehicle. After describing the evolution algorithm and evolving the control parameters, we utilize these values for autonomous waypoint following by the micro air vehicle
Performance Characterization of Dual-Metal Triple- Gate-Dielectric (DM_TGD) Tunnel Field Effect Transistor (TFET)
Full text linkAbstract: Since, Dual Metal Gate (DMG) technology alone is not enough to rectify the problem of low ON current and large ambipolar current in the TFET, therefore, a novel TFET structure, known as dual metal triple-gate-dielectric (DM_TGD) TFET, has been proposed. We have combined the dielectric and gate material work function engineering to enhance the performance of the conventional FET. In the proposed structure, the gate region is divided into three dielectric materials: TiO2/Al2O3/SiO2. This approach is chosen because high dielectric material alone near the source cannot improve the performance due to increase in fringing fields. This paper presents the detail processing of the proposed structure. We have evaluated and optimized the dc performance of the proposed N-DM_TGD TFET with the help of 2-D ATLAS simulator. The results were compared with those exhibited by dual metal hetero-gate-dielectric TFET, single metal hetero- gate-dielectric TFET and single metal triple-gate-dielectric TFET of identical dimensions. It has been observed that the DM_TGD device offers better transconductance (gm), lower subthreshold slope, lower ambipolar current and larger ON current
Application of Wave Technologies for the Preparation of Fuels Containing Organic Waste Pyrolysis Products
Full text linkProducts of fast pyrolysis of organic materials (bio-oil) have such advantages as ease of storage and transportation, production from renewable raw materials, but have not yet found wide application as motor and boiler fuels. The article describes the results of research aimed at obtaining such fuel containing petroleum fuel oil and bio-oil as the main components. Direct mixing of these components is a difficult task due to their chemical incompatibility. Its solution required the development of technology and devices, which was the purpose of the presented research results. The research methodology was based on mathematical modeling of the processes of mixing fuel components, analysis of its results, their transfer to natural samples and their experimental study. As a result, a technology and design of mixers were developed that made it possible to obtain a stable mixed fuel containing fuel oil and bio-oil in the following proportions of the mass ratio up to 50:50. The obtained results confirmed the correctness of the chosen approach, which made it possible to develop new technology and equipment to achieve the stated research goal
A Modified Perturb and Observe Algorithm in Photovoltaic Maximum Power Point Tracking System
Full text linkAbstract: The power output of the photovoltaic (PV) array is nonlinear, and maximum power point tracking (MPPT) is required to boost the efficiency of solar energy generation. The traditional perturb and observe algorithm is frequently used, but it is difficult to comprehensively consider the tracking accuracy and response speed at the same time. Misjudgment occurs when the solar insolation changes drastically. In view of these shortcomings, this paper presents a variable step size threshold search algorithm. The modified algorithm can quickly track the maximum power point and restrain fluctuations near the maximum power point. Matlab is utilized to simulate and prove the effectiveness of this modified algorithm