Mobius

[jokiin]

Purely out of interest, do any 1080p dashcams without active cooling work with temperatures around ~47°C?

Ambarella are good for up to 70°C operational temp

 

[niko]

Active cooling means some fan? I have many dashcams and in this summer I tested the Hyundai R700, the Itronics ITB-250HD and the Livue LB300 and I didn't have any problem during the whole summer and my car is running all day under direct sun all summer. Here is a video about the mount of these 3 dashcams.
The video was recorded by the ITB-250HD at 6000kbps and this is the only available bitrate for its 720p recording resolution. But this camera was more protected from direct sun. More than 100 summer days it was working perfect without any missed video. All cameras were in auto power on mode.


I am interested from about a year also about the Android TV sticks and I saw many of them have a lot of holes just for head dissipation and for example for the MK908 model was released the MK908II model which have more vent holes (not the holes was the reason of release, but an external antenna). Your idea about the heatsink outside dissipation is good, but couldn't some smart holes to help more?
Regarding the metallic case, I have also the 808 #26 which have a metallic case and it is very hot, sometimes I don't know if I can keep it in my hand, but at least I can keep it, but the Mobius heatsink is much cooler than the whole metallic case of #26. Comparing these 2 cameras temperatures I don't understand why people are worried about the Mobius heat. Of course I saw some youtube video with some melted Mobius and another strange thing is that I suppose that camera didn't came from a dashcam usage.

Another thing is that I would prefer the heatsinks to be black, not silver. But maybe adding some black paint will stop some heat dissipation?


I the past I was testing the velcro with a 808 camera, but I don't like it because:
- the camera was not perfectly fixed and is vibrating
- one part of velcro must be sticked to the camera. I want it "clean".
But your mount is the smallest possible and I like it for this. Also we can see that the actual USB solution is good for your setup.

I will open a thread about Mobius mounting solutions.

enjoy,
Mtz

Active cooling means some fan? I have many dashcams and in this summer I tested the Hyundai R700, the Itronics ITB-250HD and the Livue LB300 and I didn't have any problem during the whole summer and my car is running all day under direct sun all summer. Here is a video about the mount of these 3 dashcams.
The video was recorded by the ITB-250HD at 6000kbps and this is the only available bitrate for its 720p recording resolution. But this camera was more protected from direct sun. More than 100 summer days it was working perfect without any missed video. All cameras were in auto power on mode.


I am interested from about a year also about the Android TV sticks and I saw many of them have a lot of holes just for head dissipation and for example for the MK908 model was released the MK908II model which have more vent holes (not the holes was the reason of release, but an external antenna). Your idea about the heatsink outside dissipation is good, but couldn't some smart holes to help more?
Regarding the metallic case, I have also the 808 #26 which have a metallic case and it is very hot, sometimes I don't know if I can keep it in my hand, but at least I can keep it, but the Mobius heatsink is much cooler than the whole metallic case of #26. Comparing these 2 cameras temperatures I don't understand why people are worried about the Mobius heat. Of course I saw some youtube video with some melted Mobius and another strange thing is that I suppose that camera didn't came from a dashcam usage.

Another thing is that I would prefer the heatsinks to be black, not silver. But maybe adding some black paint will stop some heat dissipation?


I the past I was testing the velcro with a 808 camera, but I don't like it because:
- the camera was not perfectly fixed and is vibrating
- one part of velcro must be sticked to the camera. I want it "clean".
But your mount is the smallest possible and I like it for this. Also we can see that the actual USB solution is good for your setup.

I will open a thread about Mobius mounting solutions.

enjoy,
Mtz

There are different types of velcro.
Standard ones I agree with you, they dont have strong firm hold, but 3M double lock is very strong and steady, especially for such a small lightweight dash cam like mobius.

Other option is magnetic mount instead of velcro which I am working on at the moment.

About having heat sink in black colour I dont know. Usually black colour attracting a light, silver colour surfaces bouncing back light.

 

[Isoprop]

Ambarella are good for up to 70°C operational temp

The developer has set the max. environmental temperature at 47°C. This goes for all the components. Other than the DSP, the CMOS module also needs to be kept cool. Although completely different, the modules used in the #16, #18 and co. were also allergic to heat and blue ghosting under low light conditions was the result of excessive heat.
Die temperatures or component surface temperatures are always much higher than temperatures measured on the heatsink. You can't touch the DSP surface after the camera has been recording for a short while, but the heatsink is still quite cool.
The heatsink on the Mobius does not make perfect contact to the DSP because surrounding electrolytic capacitors are higher than the DSP itself. Quite a thick thermal pad is used between the DSP and the heatsink in order to prevent the heatsink shorting the surrounding components. Thermal pads are good at heat dissipation but not nearly as good as metal conductors.

 

[jokiin]

Yeah understand why but ultimately 47 is a bit on the low side for automotive use, particularly in hotter climates

 

[Isoprop]

Active cooling means some fan? I have many dashcams and in this summer I tested the Hyundai R700, the Itronics ITB-250HD and the Livue LB300 and I didn't have any problem during the whole summer and my car is running all day under direct sun all summer. Here is a video about the mount of these 3 dashcams.
The video was recorded by the ITB-250HD at 6000kbps and this is the only available bitrate for its 720p recording resolution. But this camera was more protected from direct sun. More than 100 summer days it was working perfect without any missed video. All cameras were in auto power on mode.

I am interested from about a year also about the Android TV sticks and I saw many of them have a lot of holes just for head dissipation and for example for the MK908 model was released the MK908II model which have more vent holes (not the holes was the reason of release, but an external antenna). Your idea about the heatsink outside dissipation is good, but couldn't some smart holes to help more?
Regarding the metallic case, I have also the 808 #26 which have a metallic case and it is very hot, sometimes I don't know if I can keep it in my hand, but at least I can keep it, but the Mobius heatsink is much cooler than the whole metallic case of #26. Comparing these 2 cameras temperatures I don't understand why people are worried about the Mobius heat. Of course I saw some youtube video with some melted Mobius and another strange thing is that I suppose that camera didn't came from a dashcam usage.

.....

• Yes, active cooling means some type of mechanical cooling. The most common is a fan.
• Drilling holes in the case will certainly help to dissipate the heat a bit, especially if there is airflow (e.g. AC).
• There is absolutely no problem using the Mobius under normal (30°C to 40°C) summer temperatures, but did you use your dashcams when the surrounding temperatures exceeded ~47°C in a closed car without AC? That's when there are problems with the Mobius.
• The #26 uses a Sunplus DSP which is completely different than the DSP used in the Mobius. It is an older design and produces a LOT more heat. That is most probably the reason the #26 uses an all-metal case.

I agree with you that I don't see any heat problems with the Mobius if it is used with common sense. However, it can't be expected to work properly if the temperatures are extremely high. As a rule-of-thumb I would think if a human being can withstand the temperature then so can the Mobius.

 

[DashCamMan]

A lot of cameras work fine in a closed car without AC during parking mode where the car gets very hot, particularly the Korean models from manufacturers like Itronics, FineVu and Lukas. Vicovation also has models that work well in that environment. BlackVue had a number of heat related problems with their older models but there most recent DR500GW-HD appears to work fine. They made the camera bigger, added cooling holes and initially had a low bitrate.

Some of these cameras like the BlackVue and FineVu use batteries not capacitors. So it can be done but the main difference is the size...these are all bigger cameras. They also run lower bit rates and perhaps the TI solution runs cooler than the Novatek solution.

 

[Necromancer]

What do you consider 'extreme heat'?
Temperatures here hit 45C in the summer and a parked car can easily exceed 75C.
However its parked, so the Mobius isn't working. Can it withstand these temperatures when its not operating?
When i get in i vent it and turn the A/C cooling on and the temperature in the car while im driving is below 30C (or else im sweating my ass off).
so i don't see why would it fail (based on developer specs). except the battery would probably die an early death this way, but if replaced with a capacitor we're all good no?

 

[Isoprop]

What do you consider 'extreme heat'?
Temperatures here hit 45C in the summer and a parked car can easily exceed 75C.
However its parked, so the Mobius isn't working. Can it withstand these temperatures when its not operating?
When i get in i vent it and turn the A/C cooling on and the temperature in the car while im driving is below 30C (or else im sweating my ass off).
so i don't see why would it fail (based on developer specs). except the battery would probably die an early death this way, but if replaced with a capacitor we're all good no?

I see no problem there. The 47°C max. temperature is for the surrounding temperature while the Mobius is running. As you say, such temperatures aren't good for the battery, so don't expect it to last that long. On the other hand, the battery is barely under load so that makes things better.

 

[Necromancer]

So when did you say we'll have that capacitor ready!?

 

[Isoprop]

So when did you say we'll have that capacitor ready!?

I didn't
But it won't hurt to ask one of the suppliers in China .....
Remember you'll need the upcoming firmware version in order to use it properly.

 

[russ331]

So going by the temp range it looks like I can use my second Mobius until the summer hits again in the UK and if im careful with airflow
as temps in a locked car are below that now, but I must admit that the sun rays were quite hot today, so Im still not leaving it in the car.

My first Mobius overheated and completely died...

I suggest that you transfer the battery from your second Mobius to the first. It may be restored to health, in which case you need another battery which, as you're in the UK, you can get from JooVuu...

http://joovuu.com/index.php?id_product=62&controller=product

 

[russ331]

Can you adjust the vertical tilt of your Mobius? If not, the cam may be pointing too high up at the sky which can affect the the brightness of

Link to 3 minute clip...

https://mega.co.nz/#!oEcSTbKJ!bX2UEDdd8xAXmttTOKn5H1S_cL01E7tiLw7zRSjkOIY

Uncompressed file. Standard Data Rate setting. Used an unbranded, 3 year old, 8Gb Class 4 Card... haven't got a better card at the moment.

The headlining is not perfectly horizontal, so the horizon isn't level. Too much sky, which is affecting the exposure... the day was brighter than indicated by the video. I think the USB cable managed to sneak into the upper left hand corner of the frame.

I'll have to rethink the fixing, but I won't attach the Mobius to the windscreen. It must be near invisible from outside, so I can leave the car parked without worrying about opportunist thieves.

I prefer videos I've seen taken using the standard lens, however, I chose the wide angle 'B' lens as it's better suited to dashcam use.

I may get an OTG cable to connect the Mobius to my Android 'phone. Quite a few cables on UK Amazon... not sure which one to choose. Will any work with a Motorola Defy Mini?

 

[Mtz]

The smartphone must to have USB OTG support to use it with Mobius. I think you can find a cable in many stores.

enjoy,
Mtz

 

[Gurkha9]

Most (but not all) Android phones support USB OTG.

 

[BobDiaz]

They can make the Mobius a little thicker, i don't think anyone will mind if its to fit the capacitor in.
while they are at it, they can also put a heatsink that works a little better, and call it Mobius: DashCam Edition.
As long as the mounting line of the case is at the same height (from the bottom), i don't see why it wouldn't work.
...

I keep hoping for that. Because the circuit board would be exactly the same, the only change would be the case and maybe they would only have to change the bottom part of the case to fit the larger super capacitors in. Depending on the size of the super capacitors they chose, the increase would only make the Mobius maybe 10mm (0.4 inches) thicker or less.

It could be marketed as the Mobius DC Edition....
DC = Dash Cam

 

[russ331]

Further to post #314 above, the video clip has been uploaded to YouTube...

 

[sludgeguts]

About having heat sink in black colour I dont know. Usually black colour attracting a light, silver colour surfaces bouncing back light.

Whilst that is true, waaaaay back when I did physics, we were also taught that black was a better colour to wear in the summer since - your body temp will be higher than that of the air. Slightly looser clothing will absorb this excess heat & 'lose' it to your surroundings as the clothing is blown around. As white reflects, not only does it reflect much of the heat from outside away from your body, but everything your body is trying to lose is also being reflected back at your body!

We even performed experiments with different coloured cloth on a light bulb to test this theory

 

[Mtz]

You are right, but as a dashcam, the sun never go directly on the heatsinks.

enjoy,
Mtz

 

[Necromancer]

To make it black you need to change the metal the heatsink is made of, make a composite of two (or more) metals or apply paint over it.
Either way changes the heatsink heat conduct ability and not necesserely makes it better. Not to mention additional cost.

 

[BobDiaz]

Link to 3 minute clip...

https://mega.co.nz/#!oEcSTbKJ!bX2UEDdd8xAXmttTOKn5H1S_cL01E7tiLw7zRSjkOIY

Uncompressed file. Standard Data Rate setting. Used an unbranded, 3 year old, 8Gb Class 4 Card... haven't got a better card at the moment.
...

In studying your clip it's clear that compression noise is really not an issue at the 15 Mbps rate. If possible, could you please shoot a clip at the lowest bit rate and post the raw footage?


Thanks,

Bob Diaz