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9

This would be better answered on Stack Exchange Electrical Engineering. Also see this question and answers. This is not quite the same and the answers there are OK but less than complete or correct, but it adds to the resource available. You need a battery charging controller, a PV (solar) panel capable of producing somewhat more than maximum battery ...


7

First of all you want to buy some solar panels or cells. Although they can be found on eBay for very cheap, but they not be as efficient as they say. I would say try to buy from a reputable dealer to see reviews on the product or trust that they work efficiently. Sparkfun datasheets are generally accurate and can be trusted. Most optimal configuration: Do ...


6

can I charge the battery while the arduino is still on, but on power savig mode? You can draw power from a Li-Ion battery whilst charging it, but it isn't recommended. This is because the load on the battery affects the ability to detect the different phases of charging, and determine the end-of-charge condition. Instead you should provide a bypass ...


4

You're overthinking it. Use one or more solar panels, a harvesting IC with sufficient storage, and the bare MCU and peripherals. Use enough panels and storage to run the MCU and peripherals 24/7, and to also charge the storage during the day.


4

I would actually suggest LiFePo4 for anything DIY. Not only is it safer so one false move won't cause an inferno, but it will last two to four times as long at the CONST of a little extra size and weight. Since you are just running an arduino, I would use only 1 single cell, and avoid cell balance woes. I would use a boost regulator to step up the voltage ...


3

You have selected a number of things that don't go well together. It is possible to use relays or mosfets to switch between batteries, and the Arduino could be used to measure a voltage. Or you can make a circuit with a few electronic components (e.g. a comparator). However, no one does it like that. It would be unreliable. Every solar power charging module ...


3

Look at Battery University for many good ideas. Both NimH and LiIon are viable for your application. LiIon are easier to manage well if managed well. ie do it right and they are easy to manage, but cut corners and they are easier to destroy. NimH can be abused more with a slow degradation in capacity - although complete destruction is possible. As a ...


3

I ported the BigNumber library to the Arduino in 2012. The BigNumber library is based almost entirely on the GNU "bc" library. What it does is store numbers with arbitrary precision (ie. as large as you like, and with as many decimal places as you like). For example, on the Uno you can calculate 3160 like this: 3^160 = ...


2

There's not really any difference in numerical precision. What you do get with 32-bit though is faster operations on larger data types. For instance, to add two 32-bit numbers together (uint32_t) would take many operations on an 8-bit CPY, whereas on a 32-bit CPU it would just take a couple (only one to do the actual addition - a couple to load/save the ...


2

I won't be able to tell you which solar panel or battery to use, but I can tell you how to figure that out. Battery For the battery there are a few different ways to figure this out: The most common way to do this at the professional level is to build the device and run it attached to an energy meter and measure it for an hour or two performing its usage, ...


2

Answering my own question, I think I found some way to get the solar panel face the sun. As said before, the inclinometer reads the position and makes some calculations using lookposition() function, then this happens: void lookforsun() { while ((targetElevation + 3) < realElevation | (targetElevation - 3) > realElevation) { Serial.println("...


2

Personally I wouldn't use an Arduino as a wireless sensor controller, I would use an ESP8226, which comes with WIFI interface built in. You can program this through the Arduino IDE in the same language, and its compatible with most Arduino sensors. The ESP8266 also has the advantage that it can create a WIFI network of its own, because it can act as a WIFI ...


2

There's as many ways of solving your problem as there are of skinning a cat (those poor poor cats - always getting skinned... ;) ) As you have already noted there are two basic solutions: wired or wireless. Wired does have one major advantage that you haven't really touched on (only mentioned in passing) and that is power. With a wired solution you can ...


2

As far as I understood this energyShiled accepts any input between 5-24V and output 5 - 3.3V. This specs are compatible with arduino Due. And with the solar panel. You can always power servos from seperate source or from the same battery but with seperate direct line.


2

If you have a small solar panel, you probably don't have to worry about limiting the charge current (as the battery will be able to handle more that the solar panel can supply). So the only thing left to do is prevent over-charge (i.e. disconnect the solar panel if the voltage on the battery goes above 4.2V). Protected cell can do this for you. I'm not ...


2

If you are going to design your own battery management system here are a few issues you will need to deal with: You need to understand the methods to determine the End Of Charge (EOC). This could be monitoring cell temperature, measuring cell voltage or current for patterns, or integrating current over time (coulomb counter). Different battery chemistries ...


1

You have a LiPo charger module. It's meant to charge single LiPo cells. It is therefore, the intended safe use that you can connect any single LiPo cell to it. All single cell LiPo batteries are nominally 3.7V. The only real question might be -- does the charging circuit try to charge too fast? A 2000mAh pouch LiPo can safely be charged at 1X the capacity. ...


1

You are basically describing (if you add an inductor and a diode into the mix) a simple switching regulator. That is, at its simplist, a PWM signal, some smoothing (inductor, diode, capacitor), and feedback. Use the Arduino's PWM to switch a P-channel MOSFET in the voltage supply. That switched supply is then fed through an inductor, and then smoothed with ...


1

It's not a simple matter of "calculating the power". Instead you need to: Calculate (or obtain) the current consumption of each individual sub-module or component Calculate (or obtain) the current consumption of the main MCU for each power state it operates in Calculate the current consumption of static items such as voltage dividers and power LED Then: ...


1

1)Will adding voltage divider help? You will need n voltage dividers, one for each solar panel. 2) What is the limit of Arduino of Voltage Divider? There is a limit on the equivalent Thévenin resistance of the voltage source connected to the Arduino analog inputs. It should be no larger that 10 kΩ, otherwise you risk cross-talk between the channels....


1

If you need to charge it and rum at the same time, I would recommend getting a Poweboost module from Adafruit. They can handle both, and they also have a low battery indicator.


1

I am not sure if an Allegro ACS712 30Amp chip could handle the voltage/current of my system which is usually over 60v dc and 4-5 amps. Easily. It's designed for mains voltages up to 30A. You're using a fraction of that. You could even use the 20A version to get more accuracy and resolution. The confusing part here for me is that the solar panel is ...


1

Firstly, solar panels inside a car is pretty pointless. Solar panels need to be in direct sunlight to be effective. Having them inside a car means they're not going to be in direct sunlight, so they're not going to be able to generate anywhere near enough power - unless they are massive, in which case where is the child going to sit? Yes, you could put them ...


1

First, panels that you can use... There are a few at Adafruit (here, here or here) You just want to check that the barrel jack and plug are the same size. I couldn't find dimensions in the documentation for the energy shield so you may need to dig a little deeper or just swap it for one that you know will work. Also, the question about how long it will ...


1

There are lots of circuits for charging a SLA battery from a solar cell. You need 14.4V input, so you need to ensure that the output of you solar cells is going to be at least 14.4 for enough hours to charge your battery. This means you will need to know the output current of your charging circuit and do a fair bit of maths. Charging a lipo battery will ...


1

The pot is actually part of the feedback mechanism, so you can just feed it a fixed voltage (based on PWM duty cycle). See the second diagram on page 9 of the datasheet You could however replace it with a digital pot (not necessarily 10k).


1

No. The switching frequency of the LM2596 is 150kHz, but the sampling frequency of the Arduino is only 10kHz (on a good day). You won't be able to adjust the PWM quickly enough to fine-tune the LM2596 output voltage. The LM2596 uses the 1.23V feedback voltage to change what it's doing. But the feedback voltage will only change as fast as the Arduino can ...


1

If it runs on electricity it definitely consumes power, its only how much the real question is. Since you are working with electronics I am going to assume that you have a multimeter, if you dont have one. Its about time you did, doesnt cost much and will save you a ton of time debugging. Nearly every multimeter has an onboard ammeter (the accuracy will ...


1

This is a classic system where PID will really pay off. Basically this will allow you to tune your system so that if you are off by 5 degree it will open the relays for 3 seconds. But if you are off by 1 degree it will open them for half a second. (Or whatever works for you). It might be tricky for you to get right but it will give you the smooth response ...


1

Rough block diagrams below show two ways this can be achieved - "Easiest" costs least but is inefficient. "Better" uses PV panel output more efficiently. Details of either can be discussed if of interest. 'Schottky diodes' should be used to minimise losses. (1) "Easiest" Connect PV panel to battery with diode. Panel is clamped to battery voltage (+ ...


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