Practical Model
figure above shows the practical model
The figure above show the practical model for the project design, the control devices discussed earlier are soon with arrowheads, the figure is not clear due to image compression, the read is advised to zoom at the figure.
The microcontroller circuit on the figure above; shows how it is able to relay the given commands by the Rpi3; this can be seen at the top right corner of this figure. This is achieved using a serial communication between the major devices, their baud rate (the speed of serial communication measured in bits per second (bps)) is much high; at 9600 bps rate and a greater baud rate can be used. As this design is dependent on the serial communication to relay the control behaviour, this hugely benefit the design, due to GPIO pin limitations of the Rpi3, the design implemented the physical security elements on the µC side; the Rpi handles the access control to the security elements.
The implementation of the Practical model was design on bread boards, so to easily implement the design functionality, the major control devices as seen on the figure above
Both figures show the desired design outcome of the schematic and the user interface that will be used to trigger the control behaviour events
Firstly the screen display “Keyless parcel counter kiosk”, which is the identifier of this system. Also the interface displays options: Home, Store a Parcel, Retrieve A Parcel, Help, About Us, this are the options that the user will choose from when using system interface. And the software part which is discussed earlier will handle the behaviour of each and every option that the user selects. The events on the screen are operating on the raspberry pi that is connected using HDMI to the laptop screen.
The connection of keypad, Microcontroller, relay, ADC, buttons and Dalen Pair Interface are all mounted on the breadboards. The magnetic lock is placed is a sense that we can observe it mechanism when the microcontroller triggers it. We placed and removed a certain weight on top on top of the weight sensor to observe the reading on LCD, and is sending connect values to the raspberry pi.
The power supply was placed to supply the voltage of 11.55V (12V) to the locks and the raspberry pi supplied the microcontroller with 5V. Also a raspberry pi is powered using a phone charger so it won't cause any damages. Finally if the user selects Store a Parcel, password is generated and the magnet lock is trigger to open a storage if empty. And if Retrieve a Parcel is selected and the entered password is correct using keypad, then the lock unlocks.