The code for the Hyperloop Pod Control systems

• Core: the core C controller.
• ODS: receive logs from the pod over TCP
• Client: client (telnet) for interacting with the pod remotely

• BBB: Beagle Bone Black, an ARM micro-controller
• IMU: Inertial Measurement Unit, a really sick accelerometer
• ODS: OpenLoop Data Shuttle: the server that the pod sends telemetry data and logs to.

There is more documentation in this repository and on the OpenLoop Google Drive

• Core Control Program Documentation

The following is a high level getting started geared for Openloop developers

To fire it up locally on your mac you need 3 terminal windows and some clang

• You will need Xcode if you are developing on a Mac in order to get clang

• You will need a standard build environment if you are developing on Linux.

  • You may use a clang/llvm stack or a gcc stack, we support both

• You will also need a semi-sane Python environment, set that up on a mac with:

  sudo easy_install pip
  sudo pip install virtualenv
  

1. Clone this repo somewhere safe, then cd into it.

mkdir ~/dev
cd dev
git clone [email protected]:openloopalliance/hyperloop-core.git
cd hyperloop-core

2. Clone the appropriate support repo in ~/dev/hyperloop-core for the IMU

• Real Version

  git clone [email protected]:EdHurtig/libimu-private.git libimu
  

  Note that it must be cloned as "libimu" not "libimu-private"
• Public Stub Version

  git clone https://github.com/openloopalliance/libimu.git
  

3. Build the libimu project so that the hyperloop-core project has an IMU implementation it can use

   cd libimu
   make && make install
   cd ..
   

4. In a NEW terminal window, Clone the ODS repo somewhere, this one can be cloned in ~/dev or within your ~/dev/hyperloop-core folder. We will call this window the ODS Terminal Window

   git clone [email protected]:openloopalliance/ODS.git
   cd ODS
   

1. In the ODS terminal window, fire up the ODS server: type make run-ods

→ make run rm -f server.out server.err test-data.txt *.csv pip install -r requirements.txt Requirement already satisfied (use --upgrade to upgrade): influxdb==3.0.0 in /Users/ehurtig/dev/hyperloop-core/.env/lib/python2.7/site-packages (from -r requirements.txt (line 1)) Requirement already satisfied (use --upgrade to upgrade): python-dateutil==2.5.3 in /Users/ehurtig/dev/hyperloop-core/.env/lib/python2.7/site-packages (from -r requirements.txt (line 2)) Requirement already satisfied (use --upgrade to upgrade): pytz==2016.7 in /Users/ehurtig/dev/hyperloop-core/.env/lib/python2.7/site-packages (from -r requirements.txt (line 3)) Requirement already satisfied (use --upgrade to upgrade): requests==2.11.1 in /Users/ehurtig/dev/hyperloop-core/.env/lib/python2.7/site-packages (from -r requirements.txt (line 4)) Requirement already satisfied (use --upgrade to upgrade): six==1.10.0 in /Users/ehurtig/dev/hyperloop-core/.env/lib/python2.7/site-packages (from -r requirements.txt (line 5)) ./server.py Starting TCP Server on 0.0.0.0:7778

#### Pod controller

1. In the first terminal window (in `hyperloop-core`), fire up the core
   controller. type `make run` again
    ```
    → make run
    cd core && /Applications/Xcode.app/Contents/Developer/usr/bin/make run
    /Users/ehurtig/dev/hyperloop-core/core
    rm -f *.o *~ core
    gcc -Wall -std=gnu99  -pthread  core.c main.c imu.c braking.c lateral.c logging.c height.c pod.c pod-helpers.c commands.c commander.c   -o core
    ./core
    [INFO]  [main] {main.c:65} POD Booting...
    [INFO]  [main] {main.c:66} Initializing Pod State
    [WARN]  [get_pod_state] {pod.c:92} Pod State is not initialized
    [DEBUG] [init_pod_state] {pod.c:61} initializing State at 0x1057f0240
    [INFO]  [main] {main.c:73} Loading POD state struct for the first time
    [INFO]  [main] {main.c:76} Registering POSIX signal handlers
    [INFO]  [main] {main.c:83} Starting the Logging Client Connection
    [DEBUG] [logging_main] {logging.c:230} [logging_main] Thread Start
    [DEBUG] [log_connect] {logging.c:95} Connecting to logging server: pod-server.openloopalliance.com
    [NOTE]  [log_connect] {logging.c:130} Connected to pod-server.openloopalliance.com:7778 on fd 5
    [INFO]  [logging_main] {logging.c:244} punching boot_sem to proceed
    [INFO]  [main] {main.c:101} Booting Command and Control Server
    [DEBUG] [commandServer] {commander.c:224} Starting TCP Network Command Server
    [NOTE]  [commandServer] {commander.c:231} TCP Network Command Server Started on port: 7779
    [NOTE]  [commandServer] {commander.c:239} === Waiting for first commander connection ===
    ```

2. The controller is is waiting for an operator to connect to it. This is the
   first of many safety features that ensure that the pod does not "run away".
   To connect to the controller, *switch to a third terminal window* and type:

telnet localhost 7779

You should be prompted with the controller CLI.  This is a basic command
line for interacting with the pod.  Should you disconnect prematurely, the
pod will enter emergency mode as a safety measure.

→ telnet localhost 7779 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. OpenLoop Pod CLI 0.0.1-alpha. Copyright 2016 This tool allows you to control various aspects of the pod - TCP:7779 - STDIN

Available Commands:
 - help
 - ping
 - ready
 - brake
 - skate
 - status
 - emergency (alias: e)
 - exit
 - kill

>
```

3. The pod will then start the core controller loop. This loop reads data, Makes a decision on it, and then adjusts any control surfaces. However, In order to tell the pod to turn on the skates, you need to transition it to the Ready state. This allows for pre-flight inspection of the pod before the controller takes over completely. To inform the controller that the pod is ready to go, issue the ready command on the Controller CLI that you just connected in step 4.

4. The controller will start the skates and monitor the IMU for motion in the +X direction. As soon as it records this, it will change it's state to Pushing. As soon as the acceleration drops to -X, the pod will set it's state to Coasting. Finally as soon as the X position is determined to be approaching the end of the track, the controller will engage the primary brakes and set the mode to Braking. If the controller detects an error in the sensor readings at any point it will declare an Emergency

Most of the tasks you will need to do are handled by Makefiles. There is a top level Makefile in this repository that provides a few helpful targets.

• Just typing "make" will compile all the projects
• run: Will start up the core controller (the thing that runs on the BBB)
• run-ods: Will start up the OpenLoop Data Shuttle server.

The code running on the BBB is mostly written in a single C application with a few different threads for critically different tasks. This minimizes the complexity of the application and dependency tree, however it does have a few down sides. For one, operations on the core control loop absolutely must not block, and care must be taken to ensure that any I/O that occures in the core control loop will not lock up the controller. O_NONBLOCK is the best way to prevent blocking on a file descriptor. select and poll will not always indicate actual data available and may still allow a blocking read to occur.

Anything running at the control point is fair game though. The control point is not limited in resources like the BBB so the only rule we really impose is that it works, it's tested, and it is reliable. We will have a full Dell R7** server running in the control area to receive and process data from the pod. The server will be virtualized with a VMware vSphere hypervisor that can host dozens of virtual machines at once. We hope to keep the control point simple for the time being though, so this is mostly over-preparing

Pep8 for Python, clang/llvm for C (clang-format -i -style=llvm <file>)

See the LICENSE for full licensing details.

In summary, (you still need to read the whole thing), this code is for OpenLoop and OpenLoop only. It is shared with the world for the benefit of observers and potential developers. If you wish to utilize this code in any way, you must contact us first and receive written permission to utilize the source for the purpose you require.

Lastly, DON'T trust this code to work for your HyperLoop pod, or your project. This code is only being verified and tested on the OpenLoop platform.