What are ESCs used for in ROVs?


#1

Can someone explain to me the role of ESCs in the ROV’s electronics?

Right now I just have all my bilge pump motors hooked up to PWM pins on an Arduino Mega on bottomside, interfaced through a TLC5940NT chip, but I’m looking at other people’s ROV documentation and it seems that using ESCs is very popular.


#2

@allai,

For hobby purposes there are basically two types of motors: brushed and brushless.

Your bilge pump motors are brushed motors and their direction can be reversed by reversing the polarity of the battery supplying the motor by using your TLC5940NT chip or an Electronic Speed Control (ESC) designed for brushed motors. However if you decide to buy ESCs for your bilge pump motors make sure that you get ESCs that provide both forward and reverse. There are many brushed ESC designed for RC model planes that do not provide reverse.

The motors in the OROV ROV are brushless motors and require an ESC designed for brushless motors.
The OROV ESCs provide both forward and reverse and not just forward only.

Regards,
TCIII AVD


#3

What is the ESC Open ROV pairs with their motors?

I’m not seeing any available to buy in their store.


#4

@jwlj,
According to the OROV 2.8 Controller Board BOM, the ESCs are either Afro 12 or 20 amp ESCs that must be reversible (have forward and reverse with neutral at 1500us).
I believe that OROV is presently using the Afro 12 amp ESCs that have been programmed for forward and reverse and not just forward only.
Regards,
TCIII AVD


#5

Thank you.

I’m surprised they don’t have these listed on their site for sale.

Appreciate the help! :slight_smile:


#6

@jwlj:

We sell a lot of Controller Boards, which come with the ESCs pre-installed and pre-programmed. In years past, most people who were scratch building ROVs were comfortable with the idea of buying ESCs and other parts from HobbyKing, and re-flashing them as necessary. But maybe that situation has changed, and perhaps we should look into selling ready-to-go ESCs. For instance, Blue Robotics sells re-flashed ESCs to mate with their thrusters.

If we were to sell re-flashed Afro ESCs for use with the DST-700 motors, they would have to be at a significant markup from HobbyKing prices, since we would have to unbag them, put them on a jig to reflash them, label them, and then re-bag them and stock them as a line item. Is there enough of a market to warrant doing this? I don’t know, but I’d like to hear the opinion of others in the community.

On a final note, the Controller Board is designed to handle motor loads of about 7-8 amps. Although the board will fit 20 amp ESCs, that is done for supply chain management only- if 12A ESCs are out of stock when we’re doing a production run of Controller Boards, we can use 20A ESCs in their place.

-W


#7

Thank you for the reply.

If it helps, I am considering the Blue robotics ESC’s only because they are pre-flashed.