I just got my UDOO and since I'm using this in a robot I wanted to do some battery life tests. The first one took longer than expected (good thing though!) so I only got one test complete. The battery I used is a 6v 1600 mah battery pack from Lynxmotion. Tests: Idle no Wifi: 2 hours and 26 minutes. Idle with Wifi: N/A
Check out my thread here to give you the exacts. You should be able to use this to do all your battery need calculations viewtopic.php?f=2&t=104&p=1082 reply in that thread if there are any specific tests you want me to run
Nice! I would like to see more tests about battery usage. Fell free to share your results here since the Topic's title is more helpful for others who will be looking for this kind on info. Thanks!
@ DracoLlasa - Your thread is one of the reasons I wanted to give the battery test a go. I was curious how well this would work on a 6 volt pack since that level is closer to the brown out threshold of the board. Btw for anyone who wants to know the final voltage reading from the battery was about 4.8 volts before the system browned out.
if you notice the watts are pretty much consistent at every level, this means you can calculate the estimated amps based on any voltage Watts = Amps x Volts so changing the voltage to 4, 6, 7.5, 9, or 12 should be easily predicted. using a calulator like this http://goo.gl/v8wUl Use the watts from my table (they are consistent within a tenth of a watt), and change the voltage to what you want to use. This will allow you to calculate the amps drawn, and then from that will figure out how many amp hours you need a 2600 mAh battery will deliver 2600 mA when discharged over a 20 hour period, at least that is how mAh capacity is generally estimated in the industry. In think in this case a 20 hour discharge would be at about 130mA if i did the numbers right you can break it down more to figure out some rough estimates though. a 2600 mAh battery should last about 4 hours at discharge rate of 650mA. (this makes assumptions from my table.. 9 volts 100% load @ 5.5w) Actual would be a bit over 4 hours as my test showed 610mA draw at 100%, not 650mA a 2600 mAh battery should last about 8 hours at discharge rate of 325mA. (this makes assumptions from my table.. 9 volts IDLE load @ 3.3w) Actual would be a bit under 8 hours as my test showed 360mA draw at idle, not 325 if you pop open an excel sheet with some formulas you can predict most of your needs now that we have a usage baseline. As you noted already though adding USB /anything/ will cause an increase in current, including the use of the wifi adapter being on or not. The one thing i have yet to factor in is the current/Amp draw when the Arduino DUE chip (SAM) is being used. Those numbers are only based on the ARM chip (i.MX6) usage.
Draco, indeed. @Jaeg - 6V * 1600mAH = 9.6W. If your test lasts 2hrs 26 mins (2.43 hrs in decimal) then your average draw was 9.6/2.43 = 3.9W/hr. That is in the ballpark of what Draco's spreadsheet leads you to expect of course. Having said that we don't know the exact characteristics of the battery pack in question. The C/20 (the capacity of the battery if discharged over 20 hours) will be different to the C/1 rate (1 hour... you can't pro-rata and won't yield 9.6W which common sense might lead you to believe). NiMh is great as a technology but you risk causing irreversible damage by completely discharging a NiMh pack... don't do it! Also they self-discharge (5-20% on the first day, 0.5-4.0% per day thereafter according to Wiki). I note you had a 4.8v at the end of your test. Don't go below 5.0 - 5.5v (best if you measure it and stop at those values), starting voltage may be between 7.25v (directly after charging) or nearer the nominal 6.0v (a while after). Of course this battery consists of 5 x 1.2v inside the wrapper.
@jaeg - out of curiousity, are you using Linero to program the ATMEL for your bot? And are you planning on communicating real time back to the iMX6?
Yes. The idea is to have the robot be completely independent from another computer. The Linux side will also be responsible for high level operations such as vision, speech synthesis, and voice command while the Due is responsible for handling the motors, servos, low level sensors, and other various data collection tasks.
How does one do that exactly? I've not had enough time to look at it unfortunately and somehow get to the eureka moment. At this point I can see the IDE IO writing files to the ATMEL and executing what I sent it (and I've done this quite successfully), but that's not interactive with the iMX6 as the ATMEL is essentially operating in isolation with a given set of instructions. Are you then querying the ports from the iMX6 directly (which would be limiting as I believe the iMX6 can only "see" a certain number of them) or somehow getting the ATMEL to push certain data back to the iMX6 real time? Then what on the iMX6 would listen and accept this data and tell the ATMEL to do something different? Perhaps over the onboard OTG/serial? Being very new to this kind of setup myself I humbly apologize if that comes across as a very basic question. Since I'm not getting it .. but knowing this kind of active comm between the iMX6 and ATMEL is how I want to leverage the UDOO myself .. any details you can provide would be helpful.
I can use a RC battery 7.4V 10000mAh 35c? Sorry, offtopic, a cant see New treath, i cant create new thread, only post on existing post. Thank you.
1. Yah that'll be fine. 2. You have to comment in the "introduce yourself" thread first before you can create a new thread.
I think its more that you have to post in an existing thread... its a method (a frustrating one im sure) of controlling forum spam bots and such.. but either way you should be able to start a new thread.. and this is still pretty op topic so your ok... But yes assuming the connector is correct that battery should run the UDOO just fine for white a while.
Yes, you can. UDOO can accept 6-15V, needs at least 1A of current (we're still measuring exactly how much), and consumes 3.5-5W of power. You have a 10A (1000ma = 1A) battery @ 7.4V = 74W/hr. In theory your battery could last over 15 hours (74Wh / 5W), depending on what you have it doing. Be careful, looks like you have a LiPo battery. You need the right charger and you need to observe the instructions carefully. In practice a LiPo is good for 80% of it's rating (which is pretty damn good). Don't go further than that otherwise you'll potentially harm the batteries. So in the above example you'd get 12hrs rather than 15hrs.
and be carefull to not drain it lower than 3.1 volts per cell.. any lower than that, and you risk damaging the cell. also most are chargeable at the 1c rate.. (1 x capacity) that would take roughly a hour.. but yes get a specialized lipo charger. and NEVER short a lipo
The batery is custom LiPo and made by me for work on robotics project,i have a dedicated charger and the battery is 35C. What connector type I need? I could buy the connector before receiving the board and save time. Regards.
The DC jack connector size is 2,1x5.5mm (that is 5.5mm outside diameter, 2.1mm inside). Variations of this exist but this variation might be the most useful to you because of the screw terminals. Packs of these are dirt cheap off e-bay.
