1792 réponses à ce sujet

[wowhik1]

I didn't intend to XD

[Mike118]

current design I am working on
 Minus_body.zip   6,07 Mo   0 téléchargement(s)

[Mike118]

Some m2 holes are missing in the export but they are in the final design

[Mike118]

[firened]

@Mike118 here is a simpler circuit that would enable:
- safe software shutdown.
- hw switch works normally, but will hard shutdown the load.
- hw switch works even without raspberry or if the raspberry isn't configured.

[Mike118]

Right now the correct methode for safe shutdown is : send a shutdown command on the pi and then manually switch off the robot.

The current manual switch off allow the robot to be charged.

Trying to complexify the wake up and shutdown feature can lead to weak points in the system. The first red ups we used had this flawn and we removed the added electronics to remove the problem...

In this design the on off switch is a push button or a dual position switch ?

If this is an and gate you need both the switch and the gpio set to high to drive the mosfet.

How do you switch back on the device when the raspberry is off ?

[OdorousWo1f]

does the vigibot software ever write to the pi's sd card? could just set it up as read only and then unsafe shutdowns aren't a problem. correct me if i'm wrong on that last bit

[Mike118]

Yes you can set it as read only. It is recommended if you don't need to make modifications.

[firened]

- It's a DPST switch, dual position.

- yeah the switch switches both AND Gate inputs either through the resistor when the raspberry isn't in use, or through the capacitor to start it up. I see a mistake, the switch must be a DPST with the second pole connected to GND.

- switch has to be turned off then on again to make it boot up again.

[firened]

@blacksmith

Run in CLI for help page:
`dtoverlay -h gpio-shutdown`

`dtoverlay -h gpio-poweroff`

What is the optimal behavior you would see a robot doing regarding turning it on and off?

[firened]

.
An Option:
What if we limit ourselves to a physical switch, but one that can shut down the raspberry savely?
how about the physical switch connected to a simple 15 second turn off delay IC.
a sense line to dtoverlay=gpio-shutdown for save shutdown, but after 15s it turns off no matter what.

[Mike118]

Anyone can add this kind of feature on any gpio.

[blacksmith_ch]

Am I right: GPIO3 is made to shut down and wake up the System?

[Mike118]

Gpio 3 is the i2c clock pin.

[firened]

Shutdown any button can do.

Wake up I'm not sure, perhaps GPIO3 only

[firened]

@Mike118 would you like me to set up a draft circuit for this? Probably using a monostable multivibrator like the 74HC123 or 555 timer IC.

[Mike118]

You can do it if you want yes, but I don't know if this should be integrated by default in the UPS I am working on.
Right now the ups I sent you provide all the pins to set the feature without modifying the board because each interesting point is on headers in order to let people add the features they want...

The UPS switch is in pink on your picture, and I noted the name of the pins to connect your circuit design ... For example we can design a custom right side pcb with your design on it .

[Mike118]

@fire_ned

[firened]

ok.
I don't know how important it is to have a safe shutdown. So far it was OK without.

So the new board will also not do soft shutdowns.

[firened]

1) reversing direction when driving sideways rotates the robot. I reckon that's due to the Center of Gravity not being in the middle between the wheels. It's not too bad in this video, but remember it doing it a lot more on the robot at your place @Mike118 .

1769080046642_firened_PepitoBots.mp4   923,17 Ko