Petrol Filling Robot
As we see nowadays there are so much fuel filling stations spread in all over the world. By using petrol filling robot in these stations we can minimize the time, effort, and cost. The methodology relies mainly to design robot which can take image of the car to track the fuel tank slot. Then robot will reach to the tank slot and enter its gun inside it in order to fill fuel in tank. The study recommended using VISA card automated with robot and a gripper for the robot, to enable opening the cover of the tank and closes it, so we can use that alone without any worker. The robot has three important chapters, which are constructed very will to illustrate the construction of the robot. The first chapter talk about Mechanical construction. The second chapter talk about electrical construction. The last chapter talk about control construction of the robot.v Mechanical In this chapter we shown the final form of the mechanical design of the robot and its main parts and we discussed the problems we faced during fixing them together in order to achieve the proper, desired and soft movement, which is the main wish for a mechanical design.In addition to that, we shown how the assembly ways for several parts were used (in details) and of course the selections for every component used.The resulted robot was a 3 degrees of freedom robot (serial robot) with prismatic joints since wheels and power screws where used in linear movement.Wheels were the first problem in mechanical design and the most dangerous since they waste a lot of time to recognize either them available or not in markets. Unfortunately we did not find wheels that have the desired design characteristics mentioned. So we decided to make wheels by our own hands and purchase a polyethylene rod with 3 cm diameter and prepare a cutting tool which has semicircular shape suitable for groove to be made and we made from the rod 16 wheel pieces using the Lathe machine.Four wheels were driving ones and the rest were driven by them and each couple of driving wheels were assembled by a rotating shaft (rod) that have a pulley at its center which attached to the stepper motor by a belt. See Figure 1.3 which shows the rotating shafts for the driving wheels, one for cartage 1 and another shaft for cartage 2.Cartage 1 and cartage2were formed in different measures and shapes, for each cartage, there were eight wheels; two wheels were driven by the motor mounted on the cartage and six wheels were driven by the driving wheels.Two power screws were essential for the vertical transformation for the horizontal plate which has 2 split nuts fixed between the horizontal plate and both power screws by hexagonal head screws.Bearings are considered as 1 degree of freedom (1DOF) joints to which the rotating of the shaft attached. And the rotational axis is vertical over its circular face and passes through its center. Bearings main function was to reduce mechanical friction in order to make the horizontal plate move fast and more efficiently.Belts were used to transmit rotational motion between stepper motors and their associated pulleys attached at the drive shafts in the cartages.v Motors Motors are essential parts in machines; they perform the mission of moving parts by convert the electrical power to mechanical power, this conversion of power occurs by electromagnetic phenomena, which states that the flowing current in the source circuit of the motor generates magnetic field in the motor coils causing the motor shaft to moving in the form of torque(rotating), which depends on the induced armature current, flux intensity, and other parameters related to motor structure (number of turns, poles, connection type, etc). Motors are classified in terms of various objects including source type (AC/DC).DC or AC motor types selection: In our project we need to use motors for driving the mechanisms to satisfy the desired position of the gun. It is better to use DC motors than AC motors, because the AC driving encoder for controlling the motor more expensive and less accurate than DC motors types.Our project includes three motors, one of them is a DC motor and the others are stepper motors. The DC motor found in Trucks windshield wipers is used with encoder circuit for controlling the level of the gun in vertical direction, due to the relatively large weight of robot components, and two stepper motors are chosen with theirs drive circuits for monitoring the motion in perpendicular and horizontal directions, due to relatively small torque needed to satisfy the motion.Thecontrol of speed and position of the motors was done with the appropriate circuits that are satisfy the mission, and the safety was the first concern of our project.Limit switches: In our filling robot there are six lever-operated limit switches to limit the movement in x, y, and z directions. They work as an interrupt for the microcontroller inputs. The analogue distance sensors are a common choice in most projects which requires accurate distance measurements. This sensor is more economical than others. And it provides much better performance compared with other alternatives.ADigital Camera is a device that records images which can be stored directly, transmitted to another location.v Control Image processing is a method to convert an image into digital form and perform some operations on it, in order to get an enhanced image or to extract some useful information from it. It is a type of signal dispensation in which input is image, and output may be image or characteristics associated with that image. Most image-processing techniques involve treating the image as a two-dimensional signal and applying standard signal-processing techniques to it.OpenCV is an open source computer vision library available .The library is written in C and C++ and runs under Linux, Windows and Mac OS X. There is active development on interfaces for Python, Ruby, Matlab, and other languages. OpenCV was designed for computational efficiency and with a strong focus on real-time applications. OpenCV is written in optimized C and C++. Arduino is an open-source electronics prototyping platform based on flexible, easy to use hardware and software, Arduino can sense the environment by receiving input from a variety of sensors and can affect it surroundings by controlling lights, motors and other actuators. Its microcontroller is programmed by Arduino program language. The applying code was writing to satisfy the required target of the robot, and the safety approach was the first concern. The working sequence of the robot was illustrated and described in details in the report.