Problem with arduino uno moving giant servos

someone is unwilling or unable to make the fairly significant additional investment in a hobby quality battery

Non-rechargeable batteries are so ... 1952 AD, not 2012 AD.

Expensive RC store batteries might be better, but I've been using 2200-2500 mAh
NiMH AA cells bought from Walmart and Target for years on my small robots, with
up to 16 standard servos, and they work fine. I also use 6V SLA batteries on
my heavier robots.

Many people only use Lipo, but that's more preference than actual necessity.

So, you might point out what works good in practice, what sorts of energy levels
they each produce, and what is miserable [eg, Arduino 5V buss, PP9], rather than
trying to sell the case for only what is "best". Engineering is about making good
compromises.

2200-2500 mAh NiMH AA cells especially those that are rated or recommended for digital camera use are very good general purpose power source for arduino projects. Just series them up for desired output voltage and parallel them up for more duration if desired. They can provide very good peak current loads.

I will confess that I also still use some non-rechargeable AA alkaline batteries but do buy them in bulk quantities at my local Costco warehouse store, seems to work out to be about 24 cents per cell. Note that your average drugstore wants around $2.50 each for those small 9 volt batteries that 1.50 worth of AA cells would last probably 50 100 times longer, or whatever the math is and would have much larger normal and peak current capacity.

Once educated about it, one should laugh at anyone still using a 9vdc battery in anything other then a smoke alarm or garage door remote or other device that uses just microamps of current.

Lefty

Not sure why all the battery stress. At walmart they have four rechargable AA or AAA batterys with a plugin wall charger for ~$13. Get a holder for the four batterys at radio shack (or DIY one). That should be enough to start tinkering with servos.

Not sure why all the battery stress. At walmart they have four rechargable AA or AAA batterys with a plugin wall charger for ~$13.

The idea is that, if someone is going to write a page about good practices for
connecting servos to an Arduino, then talking about how to power them should
be a prime concern. Then, noobees won't be trying to power them off the
Arduino 5V buss [like on the Arduino tutorial page] or a PP9 battery, and coming
to the forum to ask why it doesn't work.

Also, be good to talk about different energy sources and their suitability for
powering multiple servos.

Also, buying NiMh AA cells at Walmart has already been suggested 2 or 3 times
on this thread.

These are all suggestions for someone writing a tutorial page on their own.

Also, buying NiMh AA cells at Walmart has already been suggested 2 or 3 times on this thread.

I only see walmart once previously mentioned, and without a current price point (but maybe it seems like more). Anyhow, a trip to walmart and RS is quick, practical, and easy to do for a quick start.

Zoomkat

zoomkat:

Also, buying NiMh AA cells at Walmart has already been suggested 2 or 3 times on this thread.

I only see walmart once previously mentioned, and without a current price point (but maybe it seems like more). Anyhow, a trip to walmart and RS is quick, practical, and easy to do for a quick start.

I guess this is true in your part of the world.
In my part there is no wallmart and RS is a "business only" company.

oric_dan(333):
So, you might point out what works good in practice, what sorts of energy levels
they each produce, and what is miserable [eg, Arduino 5V buss, PP9], rather than
trying to sell the case for only what is "best". Engineering is about making good
compromises.

I fully agree with "Engineering is about making good compromises".
I (and I feel many engineers with me) say that for newbees you have to let them focus on 1 problem at the time. Power (in this case batteries) is number 1 in side issue creation.
So I'm proposing to make the compromise of spending to much on the power to allow to focus on 1 problem at the time.
Once it works you can always replace your good power by a cheaper alternative and reuse the good power for your next project.
I'd say it is really worth the money.

Best regards
Jantje

Walmart and Target are primary supermarket chains in the US. They
must have supermarkts in Belguim that sell AA cells. No?

I guess this is true in your part of the world.
In my part there is no wallmart and RS is a "business only" company.

Yes, it is often difficult to get parts and equipent in developing nations. The point of the walmart suggestion is that now in many common stores in the US, in the camera section, there are blister packs of AA and AAA rechargable batterys with a small charger for a reasonable price.

I don't think Belgium can be classed as a 'developing nation'.

dxw00d:
I don't think Belgium can be classed as a 'developing nation'.

Does that mean they are as developed as they are ever going to be? :wink:

dxw00d:
I don't think Belgium can be classed as a 'developing nation'.

Well, if they don't have stores that sell the rechargable AA and AAA batterys used in digital cameras, then they still have some work to do. :wink:

As I understand it, Belgium no longer has a government in which case they could be the most developed of all nations.

Duane B

rcarduino.blogspot.com

I'm glad to have helped put Belgium on your maps. :smiley:

Greetings from Belgium
Jantje

A Belgian invented Bakelite. What more do you need?

And, of course, Hergé was Belgian too.

The number of people who don't know this and the number of people who don't know bakelite are countless.
I guess Jean-Claude van Damme is better known than the previous 2 "nice to knows"

Greetings from Belgium
Jantje

Everyone knows what Bakelite is, don't they? The early TV, Radio and Telephone industries were based on it.

I don't think so.
Anyone younger than 40 not holding a engineering degree is very unlikely to know this material.
Shall we organize a poll? 8)

You're probably right. I'm certainly not in the under 40 bracket.

Hi,
Going back to an earlier response RE Information Fatigue, I am certainly fatigued but have finally found the information and managed to get blink onto an optiboot ATMega8, solution here if your interested -

Duane B.

rcarduino.blogspot.com