0

CONTEXT : I'm working on a project consisting of making an underwater robot "fish" for an aquarium . and it is mandatory to get at least 8 hours of autonomy. I'm responsible of the electrical part of the project and during all of my bachelor degree i've never got any lecture on batteries and i have no idea on how to get what is required. But i managed to do some research and try to figure it out :

1- First , I took the power consumption of all the potential componants necessary for the project (motors & pumps, Usound captors, ucontroller and a set of RF reciever and transmitters) from the specs and datasheets available.

2- I Got a battery of a 1200 mAh capacity. The battery is originally used for quadrocopters, i figured it would be good for the project since it's relatively the same thing (a software and motors). 3- Thanks to some references (Battery university, Eletropaedia), I estimated the battery autonomy. I used an ideal estimation [=Battery Capacity/sum of power consumptions] and i supposed all the components worked 100% of the time. The results i got is far bellow needed :(

Observations :

It seems that the pump is the only component to have an excessive consumption

Difficulties :

  1. Since, like i said, i have no experience in the field. I don't know if the battery i'm using is good.
  2. The pump seems to be necessary and irreplaceable. I talked to the mechanical team and replacing the pump with something else will make the project unrealistic.
  3. The 8 hours autonomy is a necessity to the project's success.
  4. The underwater environment.
  5. Dimensions (less than 8 inches long)

QUESTIONS : First, is the 8 hours autonomy doable ? what should i do to get that ? Change battery ? Change pump ? Use a totally different approach ?

LINKS : PUMP BATTERY

Thank you for your time

Ben Derrahim
  • 1
  • 1
  • This is far too broad to fit in a stack exchange question. You should probably start by seeking out and reading project reports from underwater vehicle competition teams and academic thesis. You may also need to just build a learning model and make projections based on that. On the one hand, underwater vehicles generally need a lot of weight for neutral buoyancy anyway; on the other your proposed vehicle is really quite small in volume/displacement such that you may find things a lot simpler to go a few times larger for reasons such as squeezing in mechanism and not just power endurance. – Chris Stratton Dec 31 '20 at 04:22
  • There must be a spec for energy consumption, size, weight or density and efficiency for Wh or Ah*V – Tony Stewart EE75 Dec 31 '20 at 04:22
  • The battery is 3.7V, but the pump is rated for 12V. Does it still run on 3.7V, and if so how much current does it draw when pumping water? What is the pump used for? What size is the waterproof compartment? – Bruce Abbott Dec 31 '20 at 07:31
  • The mechanical team decided to use the pump on a 6V voltage and we're using 2 batteries on serial. The size of the compartment is not decided yet. Right now im trying to anticipate the consumption to calculate a battery life for the project and see how we can reach tge 8 hour autonomy – Ben Derrahim Dec 31 '20 at 16:56

1 Answers1

0

Thank you for your answers and comments. We finally decided to change the pump with a less energy consuming system. We're testing the prototype in the next to weeks we hope we get the estimated autonpmy

Ben Derrahim
  • 1
  • 1