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Battery voltage

Hitec robotics including ROBONOVA humanoid, HSR-8498HB servos, MR C-3024 Controllers and RoboBasic
5 postsPage 1 of 1
5 postsPage 1 of 1

Battery voltage

Post by roboTT » Tue Nov 11, 2008 12:18 pm

Post by roboTT
Tue Nov 11, 2008 12:18 pm

Robofreaks!

How can i check the voltage on battery without installing addtional 'hardware' and forging anything?

I'm not a kind of electrician, just a programmer :)

Please tell me it's possible to check the voltage of battery without playing with the hardware too much...

Just wanted to prevent my RN1 from doing actions when battery goes to 'low level'..
Robofreaks!

How can i check the voltage on battery without installing addtional 'hardware' and forging anything?

I'm not a kind of electrician, just a programmer :)

Please tell me it's possible to check the voltage of battery without playing with the hardware too much...

Just wanted to prevent my RN1 from doing actions when battery goes to 'low level'..
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Post by robots42 » Thu Nov 13, 2008 11:42 pm

Post by robots42
Thu Nov 13, 2008 11:42 pm

Hi
I think the resistors are missing from the PCB because you can't reliably measure the battery voltage as it is going flat, see
http://davidbuckley.net/RS/RoboNova/RoboNovaLV.htm
and
http://www.davidbuckley.net/DB/RoboNova ... ircuit.htm
Also I don't see why you need to shut down RN. If the battery is flat RN just stops moving. You don't have to worry about deep discharging the battery, it is not Lithium Polymer so it doesn't matter. You can see RN isn't working and switch it off.
The way the US navy stores NiCad batteries is dead flat with copper shorting bars across them. Running NiCads right down is good for them.
David
Hi
I think the resistors are missing from the PCB because you can't reliably measure the battery voltage as it is going flat, see
http://davidbuckley.net/RS/RoboNova/RoboNovaLV.htm
and
http://www.davidbuckley.net/DB/RoboNova ... ircuit.htm
Also I don't see why you need to shut down RN. If the battery is flat RN just stops moving. You don't have to worry about deep discharging the battery, it is not Lithium Polymer so it doesn't matter. You can see RN isn't working and switch it off.
The way the US navy stores NiCad batteries is dead flat with copper shorting bars across them. Running NiCads right down is good for them.
David
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Post by roboTT » Sun Nov 16, 2008 5:40 pm

Post by roboTT
Sun Nov 16, 2008 5:40 pm

It is crucial for me to check the MRC voltage as the MOBO drives my UAV.

Will look around to find a solution, thanks !
It is crucial for me to check the MRC voltage as the MOBO drives my UAV.

Will look around to find a solution, thanks !
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Post by robots42 » Mon Nov 17, 2008 3:27 am

Post by robots42
Mon Nov 17, 2008 3:27 am

Well your are going to need hardware and if I was you I would start to consider if you were going about the problem of the driving UAV in the right way. Nicads do not have a gradual voltage reduction as they discharge and by the time you get to the discharge knee the processor board is on the verge of stopping working because it isn't getting enough voltage. You at least need to replace the on board voltage regulator with a very low drop-out one or run the processor from a separate supply.
David
Well your are going to need hardware and if I was you I would start to consider if you were going about the problem of the driving UAV in the right way. Nicads do not have a gradual voltage reduction as they discharge and by the time you get to the discharge knee the processor board is on the verge of stopping working because it isn't getting enough voltage. You at least need to replace the on board voltage regulator with a very low drop-out one or run the processor from a separate supply.
David
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Post by Humanoido » Mon Nov 24, 2008 4:35 pm

Post by Humanoido
Mon Nov 24, 2008 4:35 pm

The battery monitor was solved recently for nearly all robots. If you want to know how, and see the circuit, there's a generic article that you can find in Penguin Tech Magazine issue #3. This method is amazingly accurate and can be calibrated up to the full voltage of the battery, down to a low voltage just before circuits and servos begin to fail. Software is free at the download sites, and can be modified for Robonova.

http://forums.parallax.com/forums/defau ... 0&m=303010
http://www.robotinfo.net/penguin/

humanoido
The battery monitor was solved recently for nearly all robots. If you want to know how, and see the circuit, there's a generic article that you can find in Penguin Tech Magazine issue #3. This method is amazingly accurate and can be calibrated up to the full voltage of the battery, down to a low voltage just before circuits and servos begin to fail. Software is free at the download sites, and can be modified for Robonova.

http://forums.parallax.com/forums/defau ... 0&m=303010
http://www.robotinfo.net/penguin/

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