Operating Voltage (volts) Operating Amperage (milliamps) 5000mA 5000mA 80mA Operating Temperature (degree Celsius) -20 to 60 -20 to 60 -20 to 60 Consumption (mill watts) 105 64 180 Color Temperature (kelvin) 4000 to 4500 4000 to 4500 4000 to 4500 (Lumens) 360 360 360 Table 3.1.1a 4.1.2 Power Supply The power supply as a whole is what will run the Solar Powered Flower Sculpture. The group wants to power the system using photovoltaic cells, a rechargeable battery, and a microcontroller unit. By placing these in parallel, the photovoltaic cells will absorb the solar rays, which will then be converted into DC electric current. This current will then be split between the rechargeable battery and the microcontroller unit. So that the microcontroller unit does not receive excessive voltage, which would cause damage to the interior unit, a voltage divider network is added between the photovoltaic cells and the microcontroller unit. Also, so as to not completely destroy the photovoltaic cells, due to the reverse current sent out by the rechargeable battery, a diode will be placed right after the photovoltaic cells. The idea to set up the power system in this way was found from a do it yourself website called Simple Solar Circuits and the circuit looks as follows: Figure 14: Circuit Prototype
To begin, all of the components were arranged on the breadboard to match the hand drawn schematics. This implementation on the breadboard will allow further testing in a later section with the connection to the power supplies. The figures below show a side view and a top view of the Arduino Nano and TLC5940 circuit. Figure 46: Arduino Nano - Side View Figure 47: Arduino Nano and TLC5940 without LEDs Figure 48: Arduino Nano and TLC5940 with LED Wiring Combined System To breadboard test all of the individual component circuits in one combined circuit, the hand drawn schematics from earlier sections were taken into account. The combined circuit that will be implemented on the breadboard looks as follows: Figure 49: Combined System Circuit To begin, all of the components were arranged on the breadboard to match the hand drawn schematics. This implementation on the breadboard will allow further testing in a later section with the connection to the power supplies. The figures below show a side view and a top view of the combined system circuit. Figure 50: Combined System - Side View Figure 51: Combined System - Top View System with Photovoltaic Cells Figure 52: System with Photovoltaic Cells
and the simulation will be executed. The simulated display will be observed for the proper execution of the code. 6.6.2 Measuring Approach The software will be tested for proper execution of each function. The functions for the different and displays will be tested. For the testing to be considered successful the simulated display will have to match that of what the final display will look like. If an error occurs, we will try to determine if the error is with the software being developed. If a problem with the software is discovered it will be corrected and the test will be repeated. If the software is not the source of the error, it will have to be verified that the current simulator is capable of simulating the desired results from the software. If the current software is not capable of simulating the desired results than another simulator will have to be used or that particular test will have to wait for testing on the actual hardware. 6.7 Microcontroller and External Circuit PCB Interface The purpose of this testing is to accurately confirm all components of the created PCB are in working shape. Performance will be judged, and measurements will be made, which will then be analyzed by the group. These tests will be performed after the PCB design has already been implemented. 6.7.1 Testing Conditions are several factors at stake that add to our project team wanting to avoid having to radically redesign or replace components in our completed PCB. For starters, ordering new specific parts is an expensive ordeal, and shipping time is unpredictable. In addition, a lot of additional work would have to be taken after the circuit has already built, and due to the soldering process, it is likely that additional components would have to be replaced if one was found to be faulty or otherwise ineffective. Therefore, our group will take all precautions during earlier testing phases to ensure that the microcontroller and circuit interfaces meet all requirements specified, and that the parts being implemented are accurately working. Testing the completed PCB will hopefully serve to verify all needed conditions found, and reinstate the consistency of results. Still, in the event of inaccurate results found being linked to components of the PCB design, changes may need to be made in order to produce a working interface. Rebuilding the PCB is not the ideal course of action, and preparations made in earlier testing phases leading up to the creation of a working PCB serve to make such an incident unlikely, but are group is prepared to do so in order to produce a final PCB that works with precise accuracy.