omid ghahraei

Among the agricultural products, mushroom is one of the best candidates for robotic harvesting methods. One of the main problems of mushroom growers is a critical need for labor within the specified time for harvesting mushrooms, so mushroom growing is labor intensive. In this research, we attempted to develop and apply a harvesting robot for this crop to reduce the problems that growers face in terms of harvesting labor. For ease of end-effector movement between shelves, the robot was developed by Cartesian Mechanism. This robot used image processing and a computer expert system to detect the position of mushrooms on the substrate on the shelf. The end-effector acts by using a suction cup and a non-shear mechanism to harvest mushrooms from the substrate. By testing this robot on the substrate, we could harvest perfect whole mushrooms on average of 81.5% of mushrooms on the prepared substrates. Harvesting time per mushroom was obtained 12.45s, which is the amount of respective time of 8.45s more than harvesting time by labor hands, but in robotic harvesting, robots unlike humans can work 24 hours a day, continuously during growing time. An expert system also could be a valuable asset to change the grower’s strategy in terms of harvested mushrooms size and quality based on customer needs in the market.

In this paper, the effects of various parameters on the process of T-shaped copper tube bulge forming have been investigated. This evaluation is based on the properties of the copper tubes, properties of polyurethane rod and practical conditions of a bulge forming process such as the friction coefficient between die and tube, between tube and rod, boundary conditions and their constraints. The effect of each condition on a T-shaped copper tube has been explicitly simulated using the Abaqus software. The experimental results have been validated by conducting a series of experiments. After simulating the process, the effect of other parameters such as die corner radius, friction coefficient, thickness of the tube and counterpoise can be evaluated and used in practical experiments. Then, the simulation results have been compared with the obtained results from the experiments. Once the accuracy of the simulation results has been endorsed, the optimal values of different parameters have been determined using simulations. The optimal values for die corner radius, friction coefficient and counterpoise are 5 mm, 0.05 and 200 N, respectively. The findings shows the positive effect of utilization of optimal value for die corner radius, optimal value for counterpoise and lubricate on optimize forming process properties.

A ubiquitous device-widely used in many industrial applications is Computer Numerical Control (CNC) machinery. CNC controller constitutes the main part of a CNC machine, which performs the task of controlling and navigating the tool and implementation of industrial processes. Although there have been many controllers, designed and used, in CNC applications in recent years, most of them experience some limitations and disadvantages towing to the design techniques. This project aims to design and fabricate an innovative Multi Axis Automatic Controller (MAAC) to be used in CNC machinery, which has much superiority over the existing controllers and provides an ideal performance. The MAAC has a closed-loop control system, which can control and drive stepper motors, servo motors, DC motors, and hydraulic and pneumatic movement systems. An Improved accuracy and repeatability within rapid implementation of industrial process could be achieved by using of the MAAC in different CNC applications.

Hydraulic actuators are prevalence to their admirable mechanical characteristics such as ability to impose large forces quickly and there for are dramatically required at industrial applications. At the 20th century, the servo hydraulic valves were invented in order to supply more sophisticated motions but still more precise and less powered electrical actuators are preferred at more accurate manipulations because of the hydraulic systems which are not enough punctual. The main reason for this is the lack of required control performance at usual traditional analogue proportional integral derivative (PID) control strategies implemented at hydraulic actuators. In this study, a new discrete domain pole placement strategy is suggested to cover more elaborated applications.

One of the devices that are widely used in industries in recent years is computer numerical control (CNC) machinery. Many CNC controllers has been designed and employed in CNC machinery during recent years but all of them has some limitations and disadvantages due to their design and used methods. The purpose of this research is designing and modifying a novel multi axis automatic controller (MAAC) for using in CNC machinery which has more advantages compared with used controllers and has an optimized performance. By using MAAC in CNC machinery we can achieve more machining speed and repeatability in a shorter time in implementation of industrial process.