Skip to content

Commit

Permalink
Update alarms.md
Browse files Browse the repository at this point in the history
  • Loading branch information
MrinallU authored Sep 23, 2023
1 parent 1508166 commit 303b6c2
Showing 1 changed file with 4 additions and 4 deletions.
8 changes: 4 additions & 4 deletions docs/reference/alarms.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,12 +2,12 @@

In the realm of building dependable control systems, the importance of error detection and effective error-handling mechanisms cannot be overstated. Within this context, MIL presents a robust solution in the form of a live alarm system. This alarm system operates discreetly in the background of both the robot's mission and driver codebases, ready to be activated upon the emergence of errors. Notably, the alarm code doesn't solely serve to identify and address errors; it can also adeptly manage changes or updates that extend beyond error scenarios.

**ROS Alarms: A Service-Oriented Architecture**
## ROS Alarms: A Service-Oriented Architecture

The architecture of ROS alarms distinguishes itself by employing a service-oriented model rather than the usual topic-based approach. In ROS, Services act as the conduits for interaction between nodes, functioning in a request-response manner. While ROS topics enable asynchronous data exchange, services facilitate nodes in seeking specific actions or information from other nodes, awaiting a subsequent response before proceeding. This method of waiting before proceeding is known as a synchronous data exchange. This proves especially valuable in tasks that require direct engagement, such as data retrieval or computations.
If you are not familiar with ROS Services it is highly recommended that you take a look at [our page on ROS services](./services.md).

**Alarm System Logic**
## Alarm System Logic

The alarm system's functionality is more intricate than that of a typical ROS service, which usually manages operations of base types (ints, strings, etc.). In this scenario, the alarm's service server is engineered to manage the tasks of updating, querying, and processing an alarm object. ROS alarms encompass two distinct types of clients: the alarm broadcaster and the alarm listener. The broadcaster initializes and triggers alarms in response to errors or changes, while the listener monitors the broadcaster's activity and activates designated a callback function when alarms are raised. The callback function should handle the error or change appropriately.

Expand Down Expand Up @@ -68,11 +68,11 @@ Note that you can also attach some special properties to your alarm. For instanc

For a practical example of this workflow, visit: [https://github.com/uf-mil/mil/blob/master/mil_common/ros_alarms/test/rospy/callback_test.py](https://github.com/uf-mil/mil/blob/master/mil_common/ros_alarms/test/rospy/callback_test.py)

**Applications and Context**
## Applications and Context

The applications of ROS alarms span various contexts, with one notable application residing in the control of the submersible vehicle's thrust and killboard. The thrust and killboard, responsible for the sub's electronic operations, is integrally associated with ROS alarms. Upon the board's activation or deactivation (hard or soft kill), alarms are invoked to apprise users of these changes. The listener's callback function comes into play, ensuring that alarms are updated in alignment with the board's current state. This process triggered each time the board is deactivated, creates a system whereby users are continually informed about the board's status changes – essentially manifesting a dynamic live alarm system.

To delve into the implementation, visit: [https://github.com/uf-mil/mil/blob/master/SubjuGator/drivers/sub8_thrust_and_kill_board/sub8_thrust_and_kill_board/handle.py](https://github.com/uf-mil/mil/blob/master/SubjuGator/drivers/sub8_thrust_and_kill_board/sub8_thrust_and_kill_board/handle.py)

**Part 2**
## Part 2
Tale a look at all of the methods ros_alarms offers here: [https://uf-mil.github.io/docs/reference/alarms.html?highlight=alarms#module-ros_alarms](https://uf-mil.github.io/docs/reference/alarms.html?highlight=alarms#module-ros_alarms)

0 comments on commit 303b6c2

Please sign in to comment.