Speedlib documentation¶

SPEEDLIB is a python library developped as a part of the SPEED project which allows us to control trains with the DCC protocol as well as the portic of the faller brand. It is made up of 2 librairies: * The trains librairies which controls the trains * The cranes library which controls the cranes

Train API features¶

Easy to install and use
Should works on multiple RPi operating systems
Control DCC locomotives using plain Python
Set speed and direction
Set FL (lights), F1-F4 functions

Switch API features¶

Easy to install and use
Should works on multiple RPi operating systems
Control DCC locomotives using plain Python
Set biais state

Crane API features¶

Easy to install and use
Should work on any linux system
At the moment only works for Faller (c) crane model
Use Python
Set speed, move forward and backward

Warning

The train API only works on a Raspberry

Software requirements¶

python_requires = >=3.6
dccpi : It should be auto-feched when installing speedlib. If not, you can download it here : dccpi
bitstring module details. Should be auto-fetched when installing with pip.
wiringPi : download and install wiringPi
Since wiringPi uses low-level mechanisms to access pins, speedlib programs must be run as root

Hardware requirements¶

For DCC train and switch model¶

A Raspberry Pi (developed/tested on model B+)
DCC-decoder-equipped locomotives and tracks.
The Raspberry Pi needs an additional booster circuit to actually provide the signal to the tracks. (See the photo of the artwork below)
A servo motor placed on the tracks
DCC decoder for the servo motor

For the cranes¶

Faller brand portics

Installation¶

To install Speedlib, open a new Terminal window and type the following command

From pip
>>> pip install speedlib
From source
Clone the project in a local directory with Speedlib Then enter the following command line to install it
$ sudo python setup.py install

Controlling a DCC switch model¶

Here is an example of how to use the Switch library to control servo motor and set biais state

We will first import the switch library.

>>> from speedlib.dcc import dcc_object, dcc_switches
>>> from speedlib.dcc.dcc_object import DCCObject
>>> from speedlib.dcc .dcc_switches import Switch

Once we have imported the library, we will initialize the switch by specifying the address and the name of the the switch

>>> S = Switch("DCC3",3)

Now we can remove break signal by starting the controller

>>> dcc_object.start()

We can change the state of the biais

>>> S.biais = [dcc_switches.biais2, True]
>>> S.biais = [dcc_switches.biais1, True]

Note

Every switch is made of 2 biais.

To obtain information on the switch and it bias we can do a print

>>> print(S.biais)

To stop controlling the switches , we just have to put the break signal back on by stoppind the controller

>>> dcc_object.stop()

Warning

Since the switches and trains are all connected to dcc, do a dcc_object.stop () will mean that we stop both trains and switches and that is not necessarily the objective. It is better to use it only in the case where you would like to stop everything

Controlling a DCC train model¶

Here is an example of how to use the Train library to control a locomotive and its accessories

We will first import the train library that will allow us to control the locomotive as well as the accessories

>>> from speedlib.dcc import dcc_object, dcc_trains
>>> from speedlib.dcc.dcc_object import DCCObject
>>> from speedlib.dcc .dcc_trains import Train

Once we have imported the library, we will initialize the trains by specifying the address and the name of the locomotive

>>> train1 = Train("DCC1", 1)
>>> train3 = Train("DCC3", 3)

Warning

Speedlib is not yet able to set the addresses so make sure to put the correct address of the decoder otherwise it will not work. Likewise, the different instantiated trains must not have the same name or the same address.

Now we can remove break signal by starting the controller

>>> dcc_object.start()

We can then change the speed of the train, slow down, accelerate or even turn on one of the functions used by the accessories.

>>> train1.speed = 14
>>> train1.faster()
>>> train1.slower()
>>> train1.fl = True

To obtain information on the locomotive or accessories, we can just do a print

>>> print(train1)
>>> print(train1.speed)
>>> print(train1.f1)

We have two ways to stop the train:

Mettre la vitesse à 0 ou à une valeur inférieur à 5

>>> train1.speed = 0
>>> print(train1.speed)

Make an emergency stop by activating the brake signal on the tracks

>>> dcc_object.stop()

Warning

Always properly stop the program as we have seen below. Otherwise locos will receive DC current directly, and either burn or turn into DC mode (at full speed).

Controlling a Faller (c) crane model¶

Here is an example of how to use the Crane library to control cranes

To start, we will first import the crane library

>>> from speedlib.cranes import faller
>>> from speedlib.cranes.faller import Crane

After that, we will enter the ip addresses of the server contained in the microcontroller and then create our cranes.

>>> ip_1 = "172.17.217.217"
>>> ip_2 = "172.17.217.217"
>>> crane_1 = Crane()
>>> crane_2 = Crane()

We can now initialize cranes that we have just created. The initialization allows us to retrieve the ip address of the second engine to which the Spreader and Crab are connected.

>>> crane_2.init(ip_2)
>>> crane_1.init(ip_1)

We can then control the motor of the crane.With the start_for function you can move the MotorChassis forward or backward for example.

>>> crane_2.start_for(20*faller.ureg.millisecond,faller.MotorChassis,faller.MotorDirectionForward)

You can also change the speed with the change_speed method or give a speed with the set_speed method

>>> crane_1.change_speed(faller.MotorCrab, -40)

Note

It is also possible to control devices using ROS thanks to the SpeedRos library