Difference between revisions of "Power"

Latest revision as of 12:50, 2 May 2020

1 DC Supply

The AXIOM Beta developer kits ship with 5V DC power supply.

AXIOM Beta takes two 5V inputs (1x Microzed, 1x rest of electronics) and together draws 4A max, power consumption depends on operation and is in the 10-20 W range typically.

2 DC/DC Converter

Two 5V 2.5A output converters should be suitable.

For batteries both isolated as well as non-isolated DC converters are suitable.

https://octopart.com/search?q=171050601 would be an option.

3 Active Battery Mount

Battery mount for NP-F970/F750/F550 batteries to power the AXIOM Beta. Includes power usage and capacity monitoring to estimate remaining charge and time remaining.

InfoLithium Protocol

Proprietary protocol from Sony that exchanges metadata between batteries and devices. Expected data inside the protocol includes: charge cycles, battery ID, remaining total capacity, remaining current capacity, etc. Only official Sony batteries incorporate this protocol, cheap replacement parts don't and some Pro Sony cameras refuse operation with batteries without InfoLithium communication.

Decrypting this protocol could give us more insight into the battery but is not essential as we can measure the discharge curve and estimate remaining capacity rather accurately that way.

Hacking References

4 Batteries

With batteries the conveniences are being able to:

measure power consumption (AXIOM Beta does that already)
estimate time left for operation (AXIOM Beta measures voltages - it still requires an algorithmn that turns the discharge curve into a time estimate)
set low voltage warning level

An external battery needs to provide two clean and accurate 5V supplies rated at 2 Amps or more. We have witnessed a battery that could not provide the required peak currents and resulted in visible horizontal "wave" noise artifacts being visible in the image of the Beta.

For connecting the Beta to dual USB power supplies a custom-built cable is required:

Components List:

 1x  Molex   87439-0500              Pico Spox 5pin Housing
 4x  Molex   87421-0000              Pico Spox Crimp Terminal AWG24
 4x  19x36AWG - 45x40AWG             24AWG Flexible Cable
 2x  CNC Tech 1002-024-01300         CONN USB A TYPE SOLDER ASSY
 2x  CNC-Tech 1001-027-BL-01000      CONN HOOD USB A MALE BLACK
     CNC-Tech 1001-026-BE-01000      CONN HOOD USB A MALE BEIGE

We have successfully tested the following USB battery packs with the AXIOM Beta so far:

https://www.amazon.de/Anker-PowerCore-20100mAh-Externer-Akku/dp/B00VJT3IUA/

When evaluating a new battery/power supply we recommend using two USB power meters between camera and battery: https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Delectronics&field-keywords=usb+current+meter

4.1 Sony NP-F*00

Dimensions: 70 x 38.5 x Depth mm (depth varies with capacity).
Voltage: 7.2 - 7.4V
Capacity: 2600mAh (~20Wh) - 6600mAh (~48Wh)

3D Model: OnShape

On Labs: Battery System

@@ Line 1: / Line 1: @@
-Estimating power consumption, time left for shooting on portable power
-if we use some "gauge" system we can do a pretty good estimate. There is no open standard for this of course,
+===DC Supply===
-but to explain in simple words how it works :
+The AXIOM Beta developer kits ship with 5V DC power supply.
-> Each battery pack would have a chip that counts power getting in when charged, and power out when getting discharged (think like putting fuel in a car).
+AXIOM Beta takes two 5V inputs (1x Microzed, 1x rest of electronics) and together draws 4A max, power consumption depends on operation and is in the 10-20 W range typically.
-Too complicated for most cases, typical batteries have a very well known curve they follow when discharging, which can be used to calculate the remaining capacity from the voltage.
-> This information can be made available trough i2c. The chip managing this must known which kind of chemistry is the battery pack. And also adjust to the efficiency of the battery over time (a battery becomes less and less efficient over time, and 100% in doesn't mean 100%).
-IIC interface for voltage levels at the battery and storing
+===DC/DC Converter===
-simple information about the battery pack in an eeprom are
-a good idea for custom battery packages.
-> There are specific chips for this task available. They are
+Two 5V 2.5A output converters should be suitable.
-> cheap (like 0.5$).
-> So, if the camera has a somewhat constant power need,
+For batteries both isolated as well as non-isolated DC converters are suitable.
-Which it doesn't :)
+https://octopart.com/search?q=171050601 would be an option.
-We will make sure to power down everything not required
-during pauses where no recording or viewing happens.
-> we could estimate the time left using so called intelligent
-> battery pack.
-> The pack must have the chip for this to work, it's the memory
-> of past operations ofr this particular pack (averaged discharge
-> rate, power left, etc...)
-Yes, eeprom.
+===Active Battery Mount===
-> But do we want to make custom battery packs, I'm sure we don't
+[[File:Axiom-beta-concept-enlosure-02 - above.png| 400px]]
-> at this stage.
-Correct, but we can keep this in mind for later.
+Battery mount for NP-F970/F750/F550 batteries to power the AXIOM Beta. Includes power usage and capacity monitoring to estimate remaining charge and time remaining.
-> This, or provide 2 threshold levels for voltage (warning
-> and shutdown), li-po for example cannot go bellow a defined
-> voltage, else they are destroyed, or heavily impacted on
-> performance.
-> Having some discharge curves preloaded in camera can help as
+'''InfoLithium Protocol'''
-> well (at least for lipo and to a lesser extend nimh).
-> Or of course reverse engineer existing battery packs, who -I
+Proprietary protocol from Sony that exchanges metadata between batteries and devices. Expected data inside the protocol includes: charge cycles, battery ID, remaining total capacity, remaining current capacity, etc. Only official Sony batteries incorporate this protocol, cheap replacement parts don't and some Pro Sony cameras refuse operation with batteries without InfoLithium communication.
-> bet- work exactly the same, with the exactly same chips inside.
+Decrypting this protocol could give us more insight into the battery but is not essential as we can measure the discharge curve and estimate remaining capacity rather accurately that way.
-Here a chip that does exactly that, for 2-4 cells batteries which are in our intended ballpark : http://www.ti.com/product/bq34z100
+'''Hacking References'''
->>> Being able to set a warning voltage is a plus.
+* http://randybuildsthings.wordpress.com/2013/02/25/sony-infolithium-m-teardown/
+* http://www.dpreview.com/forums/post/4296759
->> Or several (which is kind of what a battery display on
->> a smartphone or consumer camera does).
+===Batteries===
+With batteries the conveniences are being able to:
+*measure power consumption (AXIOM Beta does that already)
+*estimate time left for operation (AXIOM Beta measures voltages - it still requires an algorithmn that turns the discharge curve into a time estimate)
+*set low voltage warning level
+An external battery needs to provide two clean and accurate 5V supplies rated at 2 Amps or more. We have witnessed a battery that could not provide the required peak currents and resulted in visible horizontal "wave" noise artifacts being visible in the image of the Beta.
+For connecting the Beta to dual USB power supplies a custom-built cable is required:
+[[File:Dual-USB-Power-cable-01.jpg| 1150px]]
+'''Components List:'''
+ <pre style="white-space: pre-wrap">
+x  Molex   87439-0500              Pico Spox 5pin Housing
+x  Molex   87421-0000              Pico Spox Crimp Terminal AWG24
+x  19x36AWG - 45x40AWG             24AWG Flexible Cable
+x  CNC Tech 1002-024-01300         CONN USB A TYPE SOLDER ASSY
+x  CNC-Tech 1001-027-BL-01000      CONN HOOD USB A MALE BLACK
+     CNC-Tech 1001-026-BE-01000      CONN HOOD USB A MALE BEIGE
+</pre>
+We have successfully tested the following USB battery packs with the [[AXIOM Beta]] so far:
+https://www.amazon.de/Anker-PowerCore-20100mAh-Externer-Akku/dp/B00VJT3IUA/
+When evaluating a new battery/power supply we recommend using two USB power meters between camera and battery: https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Delectronics&field-keywords=usb+current+meter
+====Sony NP-F*00====
+[[File:Sony_NPF970_1308575013000_352125.jpg | 200px| thumb | 200px]]
+* Dimensions: 70 x 38.5 x Depth mm (depth varies with capacity).
+* Voltage: 7.2 - 7.4V
+* Capacity: 2600mAh (~20Wh) - 6600mAh (~48Wh)
+D Model: [https://cad.onshape.com/documents/378fdc7cb1bbff982219eee3/w/09323a194f01c81168e0369a/e/45714b1530f14e92fe5f37b5 OnShape]
+On Labs: [https://lab.apertus.org/T736 Battery System]
+----
+[[Category:AXIOM Beta]]
+[[category: Power]]
+[[category: Batteries]]
+[[Category:Hardware]]
+[[category: Research Pending]]