Mechanical

The design has to incorporate a new attachment that the laptop needs to interface with and obtain power from a solar panel. Some characteristics features required from the mechanical side of this project are weight, compact, and a manageable setup for the user. Define components are solar module component, switch/sensor circuitry, and the other is the battery charger circuitry.

Solar Module

In designing our solar module layout, we would either construct the module in parallel or series to meet our power input to the laptop. The requirements ask Team Solar Flares to provide an apparatus that is small in size, volume, mass, and weight.

The specifications for the solar module component anticipated are:

   Dimensions of Solar Module – 10" X 24" module
   Volume of Solar Module – volume needs to implicate, flexibility so it can be
   either fold or roll up. (Volume is about the same as the laptop screen)
   Mass of Solar Module – between 1 lb and 3 lbs.

Battey Charger

The design of the circuitry will be in a compact and isolated environment. To keep the design with simplicity, the user will not have to mechanically interface with the charger. If the case is that the equipment does not function properly then the user will just need to replace the whole analog circuitry with a new one.

Switch/Sensor

The switch/sensor circuitry will implement a sensor that controls the power input to the laptop. It will be combine with the battery charger circuitry on the same circuit board for this reason is to save space and cost.

Dimensions of switch/sensor circuitry – implementing within the same circuit as 
the battery charger 4"x 4"

Electrical

The need for the electrical aspect of this project is to obtain a specific input voltage to charge the battery for most major brands of laptop computers ranging from 6 VDC to 24 VDC. The design will imply simplicity, low-cost, and trustworthy for the user to handle.

Solar Module

Design a module that would collect sunlight  to provide the power input to the battery charger.

Solar Module Electrical Specfications

Minimum output voltage:  7 Volts D.C.
Maximum output voltage:  24 Volts D.C.
Maximum Current:  less than 1 Amp
Minimum Current:  more than 100 mAmp

Battery Charger

It must be able to regulate the voltage and current from the solar module. Replacing the full capacity charge to the internal battery of the laptop. In result, all three subsystems have to interface through wiring that will not dissipate power.

Battery Charger Electrical Specfications

                    Minimum output voltage: 6 Volts dc
                    Maximum output voltage: 24 Volts dc
                    Maximum output current: 3 Amp
                    Minimum output current: 1 Amp

                   Switch/Sensing Circuit

This electrical device will sense and regulate the power from entering the laptop. The type of circuit that will be implemented into the design is by trickle charge. The trickle charge helps regulate the battery from overcharging the battery, which may lead to damage of internal components of the laptop.

Switch/Sensing Electrical Specifications

                    Minimum output voltage: 7 Volts dc
                    Maximum output voltage: 24 Volts dc
                    Maximum output current: Less than 1 Amp
                    Minimum output current: More than 100 milliamp

Environment

          Safety issues are important for the user to work under perfect conditions.  The usage of
          the apparatus will direct safety precautionary standards to prevent from harmful accidents.            
          Operating temperatures involve the overall project, which need to be enforced strictly because
          malfunction may cause short circuits within the overall project destroying the entire charging
          device.             

                     Overall Temperature Specifications
                   
                    Operating temperature specifications will determine the project from a high-quality condition                       
                     working piece versus a damaging shape component.  Here are some specifications to consider:                       
                     Storage Temperature:  -40° to 110° Fahrenheit (-47° to 47° Celsius)
                     Operating Temperature:  50° to 90° Fahrenheit (10° to 35° Celsius)
                     Relative humidity:  20% to 80% non-condensing

                      Solar Module/Battery Charger

                      All components need to be efficient in public areas with a fair amount of light. Obviously, the                        
                      user will use common sense to determine if the equipment or the apparatus is operable            
                      outdoors depending on weather conditions. Under extreme weather conditions, the recharging
                      module should be used indoors.  A proper plastic shielding will be implemented to all parts of
                      the project to prevent any electrical shock to the user.  In addition, all of the interfacing wiring
                      will be shielded or insulated with protective-coated material.    

          Solar Module Temperature Specification

         Operating Temperature Indoors:  Room temperature (73^o F)
         Operating Temperature Outdoors: above 60 ^o Fahrenheit
         Relative humidity:  maximum of 40%

         Analog Circuitry

         A circuitry that stays at constant temperature to prevent from any failure.   Since the circuitry
         will be under a plastic box, the temperature and the setting will be under room temperature or
         no higher than room temperature.  Analog components do not reach disastrous temperatures,
         which lead to burning of parts, but no such situation will occur due to the proper design
         techniques and having knowledge on topic.     

         Battery Charger Temperature Specifications

         Operating Temperature Indoors:  Room temperature (73^o F)
         Operating Temperature Outdoors: above 60 ^o Fahrenheit
         Relative humidity:  maximum of 40%

        Documentations

         The user will be provided details of documentations like a operating manual, and maintenance
         manual. 

        Operating Manual

        The manual will inform the user how to setup and manage the apparatus
         around the working area. Also, each individual subsystem will have a  
         instructive details of how to setup the solar module, battery
         charger, and overall informing the user about the interfacing wiring that will
         tell the correct connection layout to all parts of the project.   

         Maintance Manual

         A descriptive set of instructions that allow a user to maintain and protect individual parts to a
         mint condition.   

Testing

         Electrical – Using a multi-meter, a measurement is going to be obtained from the respective
                          component.
        Solar module – voltage, current, and resistance at the output.
        Battery Charger - voltage, current, and resistance inputs/outputs

        Certain types of batteries are being considered that will be tested and they are:
        Nickel Metal Hydride, and Nickel Cadmium.  To characterize the general battery pack for
        most laptops the number of cells determine the battery.  For example, a Dell
        notebook computer is an eight-cell battery source.

General

                    Reliability – functional for all types of usage
                    Low maintenance – use simple parts, easy to replace
                    Vendor Preferences – dependable and compact for travelers to use
                    Client Preferences – low-cost constraint, lightweight, and easy set-up

Home            Project

Contact us at solar@cet.nau.edu