Python Robotics

[Cheif Operations Director]

Does anyone know of any additions to python, or modules that can be used for robotics? Also how to use these new additions? If not how hard is it to code my own module that can interface with a robot. My old python thread is still alive but I wanted to focus on the topic with this thread. 

Edited August 16, 2019 by Cheif Operations Director

[wumpus]

Second hit via duckduckgo: https://atsushisakai.github.io/PythonRobotics/

A quick look at the descriptions of the sample code indicates that robotics is hard, and even python has a hard time making it easy.  Of course, you probably don't want most of the hard issues of robotics (determining the local neighborhood visually and navigating around it, or where that car door is that you need to weld) and just have to deal with things that are mostly seen by mechjeb.

Accessing the I/O functions are going to be specific to the hardware and "robotics" probably won't be a good search term.  Just go through "python", [insert platforms of choice here], and maybe "gpio" (gpio your user controlled output pins).  Also look into whatever PID routines you need (developing the parameters is probably much more complicated than writing the code, so don't worry too much about python modules here).

As far as Python/C++/C/Java goes, don't be too surprised if you eventually need to drop all the way down to assembler (C *should* work, but you basically need to understand assembler and C to do it) to say this pin needs to be that voltage.  I suspect that is what you are asking for, and it will be specific to each hardware platform (arduino, raspberry pi, gumstick, etc.).  Good hunting.

[Cheif Operations Director]

29 minutes ago, wumpus said:

Second hit via duckduckgo: https://atsushisakai.github.io/PythonRobotics/

A quick look at the descriptions of the sample code indicates that robotics is hard, and even python has a hard time making it easy.  Of course, you probably don't want most of the hard issues of robotics (determining the local neighborhood visually and navigating around it, or where that car door is that you need to weld) and just have to deal with things that are mostly seen by mechjeb.

Accessing the I/O functions are going to be specific to the hardware and "robotics" probably won't be a good search term.  Just go through "python", [insert platforms of choice here], and maybe "gpio" (gpio your user controlled output pins).  Also look into whatever PID routines you need (developing the parameters is probably much more complicated than writing the code, so don't worry too much about python modules here).

As far as Python/C++/C/Java goes, don't be too surprised if you eventually need to drop all the way down to assembler (C *should* work, but you basically need to understand assembler and C to do it) to say this pin needs to be that voltage.  I suspect that is what you are asking for, and it will be specific to each hardware platform (arduino, raspberry pi, gumstick, etc.).  Good hunting.

Ok, I am looking into it BUT this is my first time importing a library or something so how do I do that?

I was more interested in taking the robotics servo control code and applying it to the rocket parts

Edited August 16, 2019 by Cheif Operations Director

[Cheif Operations Director]

https://playground.arduino.cc/Interfacing/Python/

[Shpaget]

Python itself can not make a servo move, since it's software. You need some hardware capable of doing it. Have you decided on that?

Once you decide on what hardware you'll run your stuff, you can start looking at what code and libraries to include.

[Cheif Operations Director]

1 minute ago, Shpaget said:

Python itself can not make a servo move, since it's software. You need some hardware capable of doing it. Have you decided on that?

Once you decide on what hardware you'll run your stuff, you can start looking at what code and libraries to include.

Right now I am leaning toward Arduino if possible

[Shpaget]

Arduino is certainly a way. It's designed to interface with and control physical objects. Also, there are some monstrously powerful Arduino compatible boards, capable of some heavy duty math.

Finally, there are libraries for pretty much anything you can imagine.

[Cheif Operations Director]

13 minutes ago, Shpaget said:

Arduino is certainly a way. It's designed to interface with and control physical objects. Also, there are some monstrously powerful Arduino compatible boards, capable of some heavy duty math.

Finally, there are libraries for pretty much anything you can imagine.

right, It is just a pain to find them

[Cheif Operations Director]

Anyone know about PySerial?

[Shpaget]

Do you have a good reason why you want to send stuff between two devices?

[Cheif Operations Director]

3 hours ago, Shpaget said:

Do you have a good reason why you want to send stuff between two devices?

What exactly do you mean by two devices? I mean I need to get data from sensors and I need to send commands to servo motors and pyros.

[magnemoe]

Came here for cool snake robots and was disappointed  

[Cheif Operations Director]

34 minutes ago, magnemoe said:

Came here for cool snake robots and was disappointed  

lol

[Shpaget]

PySerial is for comunication between two devices, so you can run some python on a pc and have arduino send some data to be processed by that python.

[Cheif Operations Director]

1 hour ago, Shpaget said:

PySerial is for comunication between two devices, so you can run some python on a pc and have arduino send some data to be processed by that python.

how about an on/off for a servo? This sounds like what I need

I mean what are the limitations of PySerial

Edited August 17, 2019 by Cheif Operations Director

[Shpaget]

2 hours ago, Cheif Operations Director said:

how about an on/off for a servo? This sounds like what I need

Servo needs a bit more than an on/off switch to be of any use.

2 hours ago, Cheif Operations Director said:

I mean what are the limitations of PySerial

Why don't you read the documentation? It will tell you what it can do. What it can not do is directly connect with a motor. There has to be some sort of driver that will translate serial protocol to something that the motor can understand.

It all depends on what kind of motor you have in mind. Hobby servo motors for RC planes and cars usually use pulse phase modulation. There are some that can accept pulse width modulation (which may look and sound similar but is not).

Industrial servos could use a variety of protocols. For example, the ones I used in one of my projects could be controlled by a PC via USB, or with quite a few methods using several pins on the built in interface. Since I was replacing some steppers, the easiest way was to use one pin for direction, and pulse another one for each step. Of course that relies on the driver, in this case it was built in, so the hard work was already done, I just had to make sure that the software keeps track of numbers.

Of course, you can look for servos that have serial port. If you find some that are suitable for you, you're set.

But all this brings us back to several months ago when I told you that you should really figure out what hardware you're going to use before you write the software. It's much easier to fit software to hardware than the other way around.

[Cheif Operations Director]

3 hours ago, Shpaget said:

But all this brings us back to several months ago when I told you that you should really figure out what hardware you're going to use before you write the software. It's much easier to fit software to hardware than the other way around.

I haven't written the script for this yet just have placeholders to make sure the main parts of the control code works.

 

3 hours ago, Shpaget said:

all depends on what kind of motor you have in mind. Hobby servo motors for RC planes and cars usually use pulse phase modulation. There are some that can accept pulse width modulation (which may look and sound similar but is not).

Industrial servos could use a variety of protocols. For example, the ones I used in one of my projects could be controlled by a PC via USB, or with quite a few methods using several pins on the built in interface. Since I was replacing some steppers, the easiest way was to use one pin for direction, and pulse another one for each step. Of course that relies on the driver, in this case it was built in, so the hard work was already done, I just had to make sure that the software keeps track of numbers.

Of course, you can look for servos that have serial port. If you find some that are suitable for you, you're set.

https://store.arduino.cc/usa/feetech-mini-servo-120-degrees-9g

https://store.arduino.cc/usa/feetech-6-kg-360-degrees-continuous-rotation-servo

I was thinking of something like that,  I need to do more research on the matter though

3 hours ago, Shpaget said:

Why don't you read the documentation?

Ok

Where do I find the documentation?