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Quadruped Robot for monitoring terrain humidity

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Valerio
(@valerio)
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Hello everyone

I hope you had a nice day.

Today I assembled the chassis for my 4-legged robot.

The theoretical purpose of this robot is to measure the terrain humidity in small gardens.

The practical one is just to see if I can make a quadrupedal robot work both mechanically, electrically and software-wise.

Here is the chassis

Telaio Robot

It is made of polystirene foam because I wanted it to be lightweight.

In fact, the chassis in this state is so light it can stand up without powering the servos.

The legs are made of 3d printed PLA.

In the future I will add an Arduino Nano board, a humidity sensor, an obstacle sensor and a micro sd card reader to store the results, which will be read by a simple processing app.

If you have any questions, feel free to ask me.

If you have any suggestions, they are welcome.

 

Have a good day


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Will
 Will
(@will)
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@valerio

Print some extra legs while you're at it. It has been reported that PLA appears to degrade in sunlight and moist conditions after a while.

I was kidnapped by mimes.
They did unspeakable things to me.


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Valerio
(@valerio)
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@will I didn't print them myself, I used a 3d printing service.

Also, wasn't PLA degradation something that happened after at least a year outside?

Anyways, thanks for the suggestion.


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Will
 Will
(@will)
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@valerio 

Yes, the degradation isn't immediate. That's why I said "after a while", they just don't weather well.

I was kidnapped by mimes.
They did unspeakable things to me.


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Valerio
(@valerio)
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@will The robot should not stay outside for more than a few hours in a row.

And it is not really meant to  be used without repairs for more than a few weeks.


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Will
 Will
(@will)
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@valerio 

Thanks for the clarification 🙂

I was kidnapped by mimes.
They did unspeakable things to me.


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Valerio
(@valerio)
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@will You're welcome.

Do you have other suggestions?


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byron
(@byron)
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@valerio

These sorts of projects are the ones I like, so will hope to read of your adventures.  The only thing that crossed my mind was that, as the bot is made to trundle, I presume that different humidity readings are expected at different places, so some sort of location / humidity / date / time logging may be called for.  Also perhaps a temperature sensor to log the temp too as that has a symbiotic relation to humidity I think.

A final though is that I was playing with a SHT31 temp/hum sensor a few months back and I found it had the ability to briefly heat the humidity sensor before taking a reading to stop a bit of damp on the sensor from giving false readings.  I didn't know that humidity sensors did that, all cleaver stuff.  

PS I print with PTEG for outside use, though I expect PLA would only get deteriorated if it was left outside in the sun for extended periods.

This post was modified 3 weeks ago by byron

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Valerio
(@valerio)
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@byron Thank you for your suggestions.

The robot will follow a fixed pattern, it will no be remote controlled.

Therefore, I don't think it needs to log the location or time.

The temperature sensor is not an SH31, but this one:

https://www.robotshop.com/eu/en/seeedstudio-grove-moisture-sensor.html

I don't need high accuracy, so I don't think I will use temperature to get more accurate results.

Have a nice evening

 

 


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Inq
 Inq
(@inq)
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Posted by: @valerio

@will I didn't print them myself, I used a 3d printing service.

Also, wasn't PLA degradation something that happened after at least a year outside?

Anyways, thanks for the suggestion.

I heard the same.  In fact, I think people have tried to compost them and found no degradation after over a year.  I've had a few pieces outside in direct sun... they started falling apart in about two weeks.  I switched to ABS and they last a lot longer... but I've still noted degradation in those as well.

BTW... Cool robot.  Keep it coming.

VBR,

Inq

3 lines of code = InqPortal = Complete IoT, App, Web Server w/ GUI Admin Client, Access Point Manager, Drag & Drop File Manager, OTA, Performance Metrics, Web Socket Comms, Easy App API, All running on ESP8266...
Even usable on ESP-01S - Quickest Start Guide


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Valerio
(@valerio)
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@inq Thanks for your kind words


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Valerio
(@valerio)
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@byron @will @inq

Hello again, I have an update on this project

Today all the required components arrived.

Unfortunately I ended up soldering the grove connectors backwards on the PCB.

I could have used reversible cables, but I thought that it would be confusing for me to remember their right direction, so I decided to solder new connectors on another one of the five PCBs.

This time I will try to make sure that the non-reversible buckled cables can only be placed in the right direction.

But since I don't have enough pinheaders I will have to wait until next week.

Have a nice day

Valerio

 

 


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Will
 Will
(@will)
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@valerio 

Don't be discouraged, we all have a dumb from time to time (I've had plenty myself) 🙂

I was kidnapped by mimes.
They did unspeakable things to me.


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Ron
 Ron
(@zander)
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@valerio Been there got the T shirt.

It is considered poor judgement to traverse a chasm in 2 leaps.


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Valerio
(@valerio)
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@zander @will @inq @byron

Today the connectors finally arrived.

After I soldered them, I moved on to testing the movement code.

Unfortounately, one of the cables attached to the spring terminal on the PCA9685 jumped out of the spring terminal and shorted with the other wire.

My arduino is now broken, and I suspect other things might be damaged too.

Later I will take a look and what got burned and what can be saved.

The issue is I don't know how to prevent this from happening again.

Suggestions are welcome.

Have a nice day


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