Would this setup work? (Self righting mechanism)

I'm looking to build the following as compact as possible.
It's a kind of self righting mechanism.

A BNO055 sensor, 2x servos (each capable of lifting 1.6kg), an Arduino nano, and a power supply.

I popped the components I think I need into Circuito and this is what it put together for me.

The idea is, any time it is powered on, the sensor is active, If the value of tilt goes too far in one direction and remains there for more than X amount of time, one of the servos will extend X degrees until the correct orientation is restored.

I'm very new to all this, I'm ok ish with the coding side but really struggle getting my head around component compatibility and how to power and wire things properly.

So my question is, could anyone recommend the best way to wire and power this?
I'm guessing the nano can't power 2 servos of that size directly so how do I go about powering and controlling them?

It all needs to be powered by a battery, the smaller and lighter the better, but equally, it'd be good for the battery to last quite a while (at least several hours). The circuit building site I used above suggested that a 9v would be enough power to run this, but would it run for very long? If we assume a servo is activated once moving 180 degrees over a 10 second period and back again every 4 hours, how long would a 9v battery power this setup?

If you need more info on this please just say and any help or advice you can offer, however big or small would be really appreciated.

Thanks everyone!

Your setup is promising, except that the 9V battery should be replaced by a much more powerful source.

Your real problems will be the configuration of the stabilizing algorithms - see PID regulator and inverse pendulum projects.

It should work for the time specified but the 7805 is very inefficient and will drain a 9V battery fairly quickly. You don’t even need it if you replace the 9V with four 1.5V AAA batteries in series. Alternatively, if you can find 3.3V servos and use a 3.3V Arduino then you can use a single 3.6V lithium cell instead.

The servos are correctly wired with their power coming directly from the voltage regulator so no problems there.

Thanks for the replies guys, really appreciate it.
Perhaps if I give a bit more context it may help.

Long story short, someones tortoise has a habit of turning himself upside down and getting stuck on his shell.
My plan is to build this into a strap fitted around his waist. Each servo would be fitted half way up either side of his shell with a curved arm fitted that wraps up over the top of the shell.
When he's been flipped, the arm on the relevant side would then extend until he's been righted, and would then return to it's waiting position.

You say the 7805 is very inefficient, I was thinking I could use tilt switches but wasn't sure if they'd work well enough as if he didn't flip fully or was at a strange angle it may not register.

Got any ideas?

Thanks again!

How would you know the correct side to flip on? What if he flipped next to something like a stair step and could only get upright one way?
Paul

Because of the shape of his shell, he's always going to be lying more on one side than the other so that would be the preference. He could get himself wedged in between objects but then there's not much a self righting mechanism is going to do for him anyway.

I could go as far as to fit proximity sensors etc to try and detect a blocked direction for flipping but I'm trying to keep this as compact and lightweight as possible.

I'd glue a rope on top of the shell and a motor winch on top of the terrarium. Add a tilt switch that activates the motor to wind the turtle up then back down on its feet.

Haha, well glueing stuff to the shell is never advised unless absolutely necessary, and he doesn't live in a terrarium.

DrDiettrich:
I'd glue a rope on top of the shell and a motor winch on top of the terrarium. Add a tilt switch that activates the motor to wind the turtle up then back down on its feet.

I can just see it dragging the poor thing along, bumping off furniture, around chair legs, pulling over lamp stands and through the bowl of dog food!
I reckon if you're going to go to the effort of building a crane you might as well add a tortoise detector on the floor and slewing so it can lift the thing in and out of it's terrarium automatically. A large magnet that drops down and sticks to one attached to it's shell should to the trick.

to give your turtle a break, using a small stretchy velco strap apply side bars
to prevent him from tipping over.

not as much fun as servos, batteries and circuits, but would give you both a break.

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