Is any power being supplied via the tether


#1

Hi,

My group is working with the OpenROV 2.8 and we’re trying to add additional camera(s) to the system as payloads. We intend on running those cameras with a beaglebone black and have to figure out how to power the microcontroller. Our approach to this problem is to use the tenda powerline adapter to power the beaglebone and supply it with Ethernet. I know that the topside tenda adapter provides Ethernet to the beaglebone on the ROV, I was wondering if it also supplies power. My search through the forum provided a vague conclusion, that no power is being supplied. However, I wanted to confirm this.

Thanks,
Shruti


#2

Hello shruti,

welcome to the forum!

The tether does not supply any power. The electric components of the OpenROV solely rely on the two redundant battery tubes. The tether establishes a DLAN ethernet connection between the top box and the ROV. Supplying power over the tether has been discussed in a variety of threads here on the forum and comes with a variety of advantages and drawbacks (example). As far as I know some hackers have successfully used the tether as a power supply.


#3

This is not entirely correct. There is a 5V signal that is sent down the tether when you plug the USB into the topside box in order to signal the ROV to turn on. This 5V signal remains on the tether to keep the ROV on.


#4

Thanks @Brian_Grau for the correction. I was talking about power in the sense of suppling electric energy to components that consumes electric energy, which I guess was a bit misleading :slight_smile:


#5

Hi Brian

What is the source of these 5 volts and is it possible to draw more that 5V? if yes,can it be the only source to power the whole ROV ?
What do you mean by keeping the ROV on ?


#6

I supposed that the 5 V comes from the laptop and act as a switch signal to switch the rov on ,once you get rid off the signal then the rov will go off. I don’t know whether it is correct.


#7

Ok but i didn’t really get the point of the switch signal. from where this signal comes and how can i turn the ROV on or off. is that done by the software?


#8

Correct. The 5V signal comes from the USB that is plugged into the topside box.

The switch to turn on the ROV is an electrical signal that travels down the tether and turns on a mosfet on the controller board which then allows current to flow from the batteries into the rest of the system. It is all done in the electronics, not the software.


#9

I got it. Thanks a lot