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Moorebot Scout – The heat problem is bad

Moorebot Scout – The heat problem is bad

The Moorebot people said they do not implement SLAM and they let the Scout only run on two of the four cores of the ARM7 CPU because they fear heat problems.

I said they should just release two firmwares, one for people that want to use Scout as a toy, and one for developers.

But the heat problem is far worse than I thought:

Yesterday I took the scout off his charger for the first time in days to do some experimenting. Let me clarify this: He sat on his charger for many days doing nothing at all. I immediately noticed that the robot was warm, very warm. That really should not happen if Scout is completely inactive, only running his OS without actually doing anything.

So it looks like because of a design flaw regarding cooling/heat management and/or because of highly unoptimized code, the Scout has a heat problem, even if he does nothing. I can understand that this will become an even bigger problem if the CPU actually has to DO something, like SLAM. In addition to that heat  in battery-run devices always indicates wasted energy and wasted energy means shorter running times. And simply using the robot should not generate that much heat and certainly not just standing around idling. Edit: And my room temperature yesterday was around 18 to 19 degrees Celsius, I cannot imagine what will happen with a heat wave in the summer, when the room temp rises above 30 degrees Celsius.

This is bad.

I immediately removed Scout from his charger and let the battery run out.

When I find the time I will most probably dismantle Scout to have a look into it’s innards and see if something can be done. I’ve modded Vectors with a heatsink on the CPU board in the robot’s head and was able to lower the temperature significantly, maybe something similar is possible with Scout. But that – of course – is not something every user will be able to do.

Update: The CPU already has a heat sink as Colin Campbell discovered after dismantling his Scout:

Scout CPU board

 

4 Comments

  1. Rob Aaldijk

    So got mine yesterday – it worked instantly and I ran its first firmware update, but at the end of my test session when it did find the charging unit on its own, it failed to recognize it was connected… Finally, it went into a loud complaining mode making sad alarm noises :-). Could NOT get it out of that mode even with power button, had to reset it in the end…

    Was not able to test yet if this was because:

    – It was already fully charged. Should never be a problem of course

    – More likely: charger not powered for some reason. Had to connect my own loader (a Samsung telephone loader) which has the correct voltage etc. but as there is no LED on the loader no sign of if it is actually working – point for improvement!

    – Or perhaps the contacts are not 100% aligned – will have to test bit more

  2. S

    Swap the aluminum for copper, and maybe run the scout with the expansion port exposed for better ventilation. Theoretically we should be able to use the UART to power a fan or something but perhaps optimizing code is the best way to address the heat issue.

    Speaking of the UART, any tips on how to connect 6 pins to a 4-pin UART device (like USB)?

  3. Jerry Normandin

    I was testing my Scout for.two days running a 10 minute patrol once every 30 minutes. I shut the bot down Sunday night because as you stated I noticed the Scout was very warm.
    This morning I booted up the bot but there always no video feed to the Android app. I shutdown the bot and placed it on the dock again.. bot booted up, again no video. I reset the bot with the reset switch… Bot made the reset tone… I reconfigure wifi… No video.
    I placed the bot on the dock to charge for a couple of hours. Powered.up, no video. I hit the reset pin again, this time no tones, no flashing lights while charging. Either the onboard flash is corrupt or the Rockchip SOC is fried from the heat. Hopefully Moorebot will send me a new one had anyone created a recovery image ? My bot is on the dock now charging. I will give it one more try in 3 hours.

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