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Matt
02-14-2008, 03:11 PM
Hey all,

I wanted to post about the company Inspired Energy (http://www.inspiredenergy.com/) that makes advanced battery packs. I saw their stuff at a trade show awhile back and I loved it. You can actually communicate with the battery packs to pull information such as; power drain, power left, estimated time left from average current draw so far, estimated time until full charge is reached during charging. All of this stuff is really useful in robotics. If you read through this product spec sheet (http://www.inspiredenergy.com/Standard_Products/NC2560/NC2560A20%20rev1.0.pdf) you'll see what I mean. Look at page 13 for a listing of function calls.

I have long thought that this would be a great advancement for robotics if people were to build controllers that could interface these batteries to the systems that we use. Mini-computers / Bioloid / Serializer / Hitec / etc.

What do you think? Some of you in here are very advanced developers and I'm curious if you think you would experiment with these batteries? You could create a homebot that knows it's time to start looking for it's dock, or at least inform his owner "I'm tired! I need electrons!", or have a display that tells you how long you have to wait to finish recharging... One problem in robotics is that many systems don't have much knowledge about their own power supply. I see this as a nice solution.

PS: Dave from Inspired Energy wanted me to mention that they have recently come out with a new battery, the PG3665 (http://www.inspiredenergy.com/Standard_Products/PG3665/PG3665.htm) , that is designed for higher voltage & current draw users like us. (Here is their product listing page (http://www.inspiredenergy.com/Standard_Products/standard_products.htm))

JonHylands
02-14-2008, 03:27 PM
I would be a lot more interested if they included the prices on their website.

I added a really simple version of this to Seeker 2x - basically, I feed the raw Li-Poly battery voltage through a resistor divider and into one of the A/D ports of the ATmega128. This gives me a very good idea of the voltage remaining in the battery, which I can display on the 7-segment LED as a capacity value (0-9)...

- Jon

Matt
02-14-2008, 03:47 PM
If I recall I think that many of the batteries were between $79-$149 ish....

Not cheap, but not too bad for serious developers either.

DaveB
04-22-2008, 11:57 AM
Hi All,
Dave Baggaley from Inspired Energy here. (I'm new to the chat community so please be gentle with me.)

Many thanks for the lead-in Matt.

IE is a small company (55 people total) based in N. Florida & we design & build smart battery packs. All our stuff is desgined & built by us right here - soup to nuts - & our business model is ONshore INsourcing. We don't outsource our stuff offshore, so if you need to speak with the guy who wrote our firmware or designed the battery we'll put him right on the phone to answer your tech. queries. (We're certainly not the lowest cost batteries, but we have other advantages!)

We currently sell around 10% of our products into robotic applications & we have a number of reasons why we don't publish prices on our website....

... Although we do accept single-piece orders we're not really a consumer operation. Basically our business is to design & build smart batteries for OEMs to buy in volume.
... We also are not keen for our competitors to see all our pricing.
... But more than anything we like to establish a dialogue (yes I'm an Expat Brit & still spell things the old fashioned way) with our customers because we prefer to offer guidance & advice & we like to learn more about where our products are being deployed.

I too like to buy stuff by pointing & clicking outside business hours so I recognize the advantages offered by this method but for now its not where we want to take our company - hence the old-school approach.

Now to another topic that John mentioned - fuel gauging. Yes it can be done by monitoring the voltage & interpreting where you are on the discharge voltage curve.
This will yeild results much like cellphone fuel gauging which is ideal for many applications.
However as the battery ages, the overall discharge voltage drops & so a fuel gauge based on absolute voltage won't know if it is at 10% state of charge on a brand new battery, or 50% state of charge on an old one.
When you're fuel gauging to ensure that your robot maximises its work time, but still returns to the recharge station reliably without running out of battery power this is where the difference becomes key - especially as the battery ages.

Hope this helps - if you have any questions please don't hesitate to get in touch.
"Old-school" phone is 352 472 4855 x12 or email me at [email protected]

Cheers,
Dave B

Matt
04-22-2008, 12:06 PM
Hey Dave,

Thanks for stopping in. I've been shilling for you guys ever since I saw the display at Robonexus :) I really think that smart batteries will be a great addition to robotics systems. Integration is just a matter of time IMHO.

Adrenalynn
04-22-2008, 01:27 PM
Dave,

Welcome aboard, and well-writ! I like your philosophy, and will definitely have a look at your offerings in the immediate future.

archcvd
04-22-2008, 02:44 PM
Hi Dave!

I am thoroughly impressed with your company's core philosophy and the products it offers. I was wondering if someone out there was working on something like this!

My own power implementation is rather crude and I think smart batteries like these would have helped simplify the design greatly. I would love to play around with batteries like these, especially with the intelligent firmware. I'm definitely keeping an eye on this... :)

LinuxGuy
04-22-2008, 03:03 PM
What do you think? Some of you in here are very advanced developers and I'm curious if you think you would experiment with these batteries? You could create a homebot that knows it's time to start looking for it's dock, or at least inform his owner "I'm tired! I need electrons!", or have a display that tells you how long you have to wait to finish recharging...
Oh, I would love to experiment with these batteries. W.A.L.T.E.R. is currently setup for all 7.2V operation and it looks like standard NiMH batteries might not be enough to power him. I have two 7.2V @ 2800 mAH battery packs powering him right now - one for electronics only, and one for motors and servos. I'd like to add a third battery just for servos.


One problem in robotics is that many systems don't have much knowledge about their own power supply. I see this as a nice solution.
So true!

8-Dale

Wingzero01w
04-22-2008, 03:46 PM
I support the batteries i think there pretty cool from what ive seen... id love to use them in one of my bots as well.

Droid Works
04-22-2008, 05:28 PM
3.1.1. Nominal Voltage The battery nominal operating voltage is 10.8V. I like the sound of that being a 1HV owner.

4mem8
04-23-2008, 02:15 AM
These batteries sound great Dave, Just going to have another look at your site, I love the idea of monitoring what the battery does. Great potential. Thanks for sharing with us your product.

DaveB
04-24-2008, 10:32 AM
One of the cool things that may be of assistance to autonomous robot designers is that you can ask the battery questions, & these include more than just "how many minutes of runtime do you have left? (which is based on the previous 60sec average current).....

Lets say you know the current requirements of your robot during its normal activity & the battery is sitting on the home/recharging station - but hasn't been sitting there for long enough to reach full charge. (ie you have an unscheduled need for the robot to go & do something)

You can use the "ATRate" feature in the battery data to ask "If I were to discharge you at X amps, how long would you run for?" Then poll the "AtRateTimeToEmpty" field & you'll get your answer. You can then compare this result with your known time to complete the job & see if your battery is sufficiently charged to do the task or if you need to continue charging a little longer.

(If you have a wireless link to your robot, you could also feasibly ask it this same question while it is already out & about doing its work)

Another thing you can do with the data is create a "trip-computer"....
You know the operational speed of your robot, the battery knows how much runtime (reported in minutes) it has remaining so you can calculate how much "distance" remains in your "fuel tank". - handy for "Can I get home?" questions & even "Can I go & do something else & still get home?"
(Also if you find you can't get home, it may be possible to shut down some onboard systems, reduce the current drain & hence extend your remaining "distance")

Of course all this is easy for me to say - you guys have the tricky job of building the robots to do all this stuff & now I'm advocating that you implement the SMBus as well - just so that you can talk to my battery!
If you have any questions on SMBus implementation - just give us a call & we'll put you in touch with our tech guys - they love this stuff!.

Hope this helps.

Over & Out
DaveB

Wingzero01w
04-24-2008, 12:37 PM
Yeah but how are we going to get ahold of these magnificent batteries?

Matt
04-24-2008, 03:55 PM
These are some great suggestions Dave. You are hitting on the exact points I was trying to get at about how smart batteries can be so helpful in a robot.

You made me curious about this part:
>>>>"how many minutes of runtime do you have left? (which is based on the previous 60sec average current)

Previous 60 seconds in robotics might give a really skewed answer. (He could have been chilling or racing after cats) Is there a way to get a longer history out of the battery to maybe calculate an average amp draw to use with the "ATRate" function?

Alex
04-24-2008, 07:44 PM
Yeah but how are we going to get ahold of these magnificent batteries?First post (http://forums.trossenrobotics.com/showpost.php?p=6328&postcount=1) in this thread, their website (http://www.inspiredenergy.com/):D

Wingzero01w
04-24-2008, 11:00 PM
First post (http://forums.trossenrobotics.com/showpost.php?p=6328&postcount=1) in this thread, their website (http://www.inspiredenergy.com/):D

They said on the site its volume pricing, which means i would have to buy many... which i really cant do/afford... it one battery too hard to ask for :( jk.. but it would be nice to have one.

Adrenalynn
04-24-2008, 11:24 PM
Read the gentleman's post, Wingz'

DaveB
04-25-2008, 07:37 AM
Hi Guys,

My apologies about the note on the website about volume pricing. This really gets back to us not really being a consumer operation. Our revenue comes from volume sales, but we recognize that before volume sales come samples & tests & enthusiasts like you guys kicking the tyres on the technology. So we will be happy to build & ship you a single battery of any of our standard products. It is not a problem. We take Visa & MasterCard for onesie-twosie sales. (We may be old school, but we're not antediluvian :happy: )

All you have to do is call 1-888-5-INSPIRE, or send me a message (like the nice Bhuddist lady who sent me a "welcome to the robotics community" message yesterday :confused: ) or drop us an email (its on our contact page) & we'll give you the pricing for single pieces all the way up to 10,000.

We also have the mating connectors, connector boards, battery mounting guides, cables, chargers (desktop & embeddable) beltpacks & all the gubbins that you need to get the battery up & running.

- Check out the Accessories page on our website (link is on the left hand side / scroll down of all the product pages) & the mating connectors page (link in in the middle of the specification summary on the individual products pages).

To answer Matts Q about the 60sec current possibly not being truly representative...
In our standard products we can't alter the average current because the 60 sec was written into the industry standard Smart Battery Data Specification back in 1995 when we wrote it (along with Intel, Duracell, Nat Semi, Varta, TI et al).

However you can still use the AtRate to query your "worst case" runtime & compare this to your average time to empty to give you estimates of remaining runtime based on current conditions & if you were to chase a cat all the way home.

Alternatively we could create a custom version - but that would need production volume, which brings us back to Wingz concern about volume pricing !

Cheers,
DaveB

Adrenalynn
04-25-2008, 09:55 AM
Hi Dave,

Thanks for taking the time to clarify your position on selling to the enthusiast market [again]. My recommendation to Wingzero to "read your post" was made because I felt you had made that pretty clear in your first contribution here.

Just let me say again that I know I certainly appreciate your willingness to accept the additional overhead that direct-sales creates vs volume OEM sales.

I know I'll certainly be talking with you folks about a couple NH2057's when this project I'm working on gets a little more mature.

Matt
04-25-2008, 10:19 AM
To answer Matts Q about the 60sec current possibly not being truly representative...
In our standard products we can't alter the average current because the 60 sec was written into the industry standard Smart Battery Data Specification back in 1995 when we wrote it (along with Intel, Duracell, Nat Semi, Varta, TI et al).

Also, it's fairly easy for the robotics system itself to keep a log on it's own by just querying the battery every 60s and storing that for calculations.

Adrenalynn
04-25-2008, 10:23 AM
And make smart decisions about its history.

Fuzzy-logic power utilization/safe/reserve time-to-run calculations based on "virtual experience", anyone?

archcvd
06-06-2008, 09:03 AM
Oh.. Yay!

Spam :P

Alex
06-06-2008, 11:19 AM
what spam? I don't see any spam :D

archcvd
06-06-2008, 11:28 AM
what spam? I don't see any spam :D

You have great power, admin. *bows*