\documentclass[onecolumn,letterpaper,11pt]{article} %=================================================================== % Include common packages, environments, counters etc \input{./common_latex/common_latex_packages} \input{./common_latex/common_latex_lab_format} \input{./common_latex/common_latex_definitions} %=================================================================== \begin{document} \wikidoc{file=MCA.Lab04IntroBehaviors} \wikidoc{auth=mikerb@mit.edu} %=================================================================== % Build the Cover Page in an environment style easy for wiki parsing \begin{labcover} \labtitle{Lab 4 - Working With Helm Behaviors} \vspace{0.1in} %\labcourse{2.680 Unmanned Marine Vehicle Autonomy, Sensing and Communications} \vspace{0.1in} \labpng{0.75}{figs_common/header.png} \labdate{Nov 17-21 2025} \vspace{0.1in} \labauth{Michael Benjamin, mikerb@mit.edu} \labauth{Department of Mechanical Engineering} \labauth{MIT, Cambridge MA 02139} \labtoc{footnotesize} \end{labcover} %=================================================================== % Add a blank page so first body page is on the right when doubleside \blankpage %=================================================================== % Begin the body of the text %=================================================================== \section{Overview and Objectives} \label{sec_overview} %=================================================================== This lab will provide further experience with the IvP Helm to new users. It assumes some experience with the Helm, editing mission and behavior files, from the previous lab. It also assumes access to the corresponding lecture and lab overview lecture. \begin{labinfo} %\labinfoheader{Topics:} \begin{packed_itemize}[2] \item The Loiter Behavior \item Simulating UUVs (adding depth to the simulations) \item The Timer Behavior \item The Behavior updates parameter \item Constant Depth behavior \item MaxDepth behavior \item Simulated Drift \end{packed_itemize} \end{labinfo} \subsection{Preliminaries} \label{prelims} In this lab, several new missions will be created. As in the previous lab, each mission will begin by copying a previous similar mission and modifying from that starting point. Each mission folder will contain an \var{alpha.moos} and \var{alpha.bhv} file. In this lab we will create the following missions: \begin{packed_itemize} \item \var{s8\_alpha}: By copying \var{s1\_alpha}, then modifying \item \var{s9\_alpha}: By copying \var{s8\_alpha}, then modifying \item \var{s10\_alpha}: By copying \var{s9\_alpha}, then modifying \item \var{s11\_alpha}: By copying \var{s10\_alpha}, then modifying \item \var{s12\_alpha}: By copying \var{s11\_alpha}, then modifying \item \var{s13\_alpha}: By copying \var{s9\_alpha}, then modifying \item \var{s14\_alpha}: By copying \var{s13\_alpha}, then modifying \end{packed_itemize} %====================================================================== \newpage \section{Exercises} %====================================================================== %====================================================================== \subsection{Exercise 1 - Changing the Alpha Mission to Use the Loiter Behavior} \label{sec_s8} In this exercise the goal is make a version of the Alpha mission and swap out the Waypoint Behavior and use the Loiter Behavior instead. It should look something like: \vspace{0.1in} \begin{figure}[H] \centering \includegraphics[width=0.75\textwidth]{figures/s8_alpha.png} \caption{{\bf s8\_alpha:} Using the Loiter Behavior} \label{fig_s8} \gif{figures/s8_alpha.gif} \end{figure} \vspace{0.1in} \noindent You will need to do the following steps: \begin{itemize} \item Copy the \var{s1\_alpha} mission, naming it \var{s8\_alpha} \item Remove the Waypoint survey behavior (keep the return waypoint behavior) \item Add a Loiter Behavior \end{itemize} \vspace{0.1in} \noindent The Loiter behavior documentation is here: \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/bhvs/Loiter} \vspace{0.1in} \noindent The behavior block should look like that below. You can copy it into your behavior file, but try to understand the configuration parameters by reading the Loiter documentation above. \begin{fileverb} //---------------------------------------------- Behavior = BHV_Loiter { name = loiter priority = 100 condition = RETURN = false condition = DEPLOY = true updates = UP_LOITER speed = 1.3 clockwise = false radius = 6.0 slip_radius = 25.0 polygon = format=radial, x=75, y=-75, radius=30, pts=8, snap=1 visual_hints = nextpt_color=yellow, nextpt_lcolor=khaki visual_hints = edge_color=white, vertex_color=dodger_blue visual_hints = edge_size=1, vertex_size=3, label=LOITER_POLYGON visual_hints = nextpt_vertex_size=5 } \end{fileverb} %====================================================================== \newpage \subsection{Exercise 2 - Adding Depth to our Missions, Constant Depth Behavior} \label{sec_s9} In this exercise the goal is to modify the previous \var{s8\_alpha} mission to have a vehicle that operates underwater, reasoning about depth in addition to heading and speed. It should look something like: \vspace{0.1in} \begin{figure}[H] \centering \includegraphics[width=0.75\textwidth]{figures/s9_alpha.png} \caption{{\bf s9\_alpha:} A simulated UUV showing its current depth.} \label{fig_s9} \gif{figures/s9_alpha.gif} \end{figure} \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s8\_alpha} mission, naming it \var{s9\_alpha} \item Configure the Helm to reason about depth \item Configure the simulator to reason about depth \item Configure the PID controller to reason about depth \item Add the ConstantDepth Behavior to the behavior file \end{packed_itemize} %------------------------------------------------------------- \subsubsection{Configure the Helm to Reason about Depth} The Helm documentation is at the link below. In particular, Section 1.4.6 discusses the helm decision space. \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/helm/helm_as_moos} \vspace{0.1in} \noindent The helm configuration block should look like that below. You can copy it into your mission file, but try to understand the configuration parameters by reading the documentation. \begin{fileverb} ProcessConfig = pHelmIvP { AppTick = 4 CommsTick = 4 bhv_dir_not_found_ok = true behaviors = alpha.bhv domain = course:0:359:360 domain = speed:0:4:41 domain = depth:0:100:101 <-- Add this line } \end{fileverb} %------------------------------------------------------------- \subsubsection{Configure the Simulator to Reason about Depth} The Simulator documentation is at the link below. \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/apps/uSimMarineV22} \vspace{0.1in} \noindent The \app{uSimMarineV22} configuration block should look like that below. You can copy it into your mission file, but try to understand the configuration parameters by reading the documentation. The last four lines are needed with simulating depth. \begin{fileverb} ProcessConfig = uSimMarineV22 { AppTick = 4 CommsTick = 4 start_x = 0 start_y = -20 start_heading = 180 start_speed = 0 prefix = NAV turn_rate = 95 thrust_map = 0:0, 20:1, 40:2, 60:3, 80:4, 100:5 thrust_reflect = true buoyancy_rate = 0.025 max_depth_rate = 7 max_depth_rate_speed = 1.0 default_water_depth = 400 } \end{fileverb} %------------------------------------------------------------- \subsubsection{Configure the PID Controller to Reason about Depth} You will need to add the below lines to the \app{pMarinePID} configuration block in your mission file to reason about depth. \begin{fileverb} // Depth control configuration depth_control = true // or {false} z_to_pitch_pid_kp = 0.12 z_to_pitch_pid_kd = 1.0 z_to_pitch_pid_ki = 0.004 z_to_pitch_pid_integral_limit = 0.05 maxpitch = 15 // Depth control configuration pitch_pid_kp = 2.5 pitch_pid_kd = 1.0 pitch_pid_ki = 0 pitch_pid_integral_limit = 0 maxelevator = 13 } \end{fileverb} %------------------------------------------------------------- \subsubsection{Add the ConstantDepth Behavior to the behavior file} \vspace{0.1in} \noindent The ConstantDepth behavior documentation is at the below URL. \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/bhvs/ConstantDepth} \vspace{0.1in} \noindent You will need to add a configuration block like that below. You can copy it into your behavior file, but try to understand the configuration parameters by reading the documentation. \begin{fileverb} //---------------------------------------------- Behavior=BHV_ConstantDepth { name = const_depth pwt = 100 condition = DEPLOY = true duration = no-time-limit depth = 20 } \end{fileverb} %====================================================================== \newpage \subsection{Exercise 3 - Allow the User to Dynamically Change Depth} \label{sec_s10} In this exercise the goal is to modify the previous \var{s9\_alpha} mission to accept user specified changes to the commanded UUV depth, during the mission. The user should be able to toggle between commanded depths of 20 and 40 meters. Two buttons will be added to \app{pMarineViewer} to initiate the depth changes. It should look something like: \vspace{0.1in} \begin{figure}[H] \centering \includegraphics[width=0.75\textwidth]{figures/s10_alpha.png} \caption{{\bf s10\_alpha:} A simulated UUV with two new operator buttons for changing the depth between 20 and 40 meters.} \label{fig_s10} \gif{figures/s10_alpha.gif} \end{figure} \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s9\_alpha} mission, naming it \var{s10\_alpha} \item Add the updates parameter to the ConstantDepth behavior \item Add the appropriate buttons to the pMarineViewer configuration \end{packed_itemize} %------------------------------------------------------------- \subsubsection{Add the updates Parameter to the ConstantDepth Behavior} The \var{updates} parameter is defined for all IvP Behaviors. It specifies a MOOS variable from which updates to prior behavior configurations can be applied. Read more here: \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/pmwiki/pmwiki.php?n=Helm.HelmBehaviors\#sec_updates} \vspace{0.1in} \noindent You will need to add one line to the existing configuration block below: \begin{fileverb} //---------------------------------------------- Behavior=BHV_ConstantDepth { name = const_depth pwt = 100 condition = DEPLOY = true duration = no-time-limit updates = DEPTH_UPDATE depth = 20 } \end{fileverb} %------------------------------------------------------------- \subsubsection{Add Buttons to pMarineViewer} The next step is to add a pair of buttons to the \app{pMarineViewer} configuration block that allow us to command different depths: \vspace{0.1in} \noindent The \app{pMarineViewer} documentation is here (see Sec 47.1.5): \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/apps/pMarineViewer} \vspace{0.1in} \noindent You will need to add the below line to the existing configuration block below: \vspace{0.1in} \begin{fileverb} button_three = DEPTH_20 # DEPTH_UPDATE=depth=20 button_four = DEPTH_40 # DEPTH_UPDATE=depth=40 \end{fileverb} %====================================================================== \newpage \subsection{Exercise 4 - Use a Script to Randomly Change Depth} \label{sec_s11} In this exercise the goal is to copy the previous \var{s10\_alpha}, to a new mission \var{s11\_alpha}, to use a timer script to randomly change the vehicle depth between 20 and 80 meters. \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s10\_alpha} mission, naming it \var{s11\_alpha} \item Add the \app{uTimerScript} to the Antler block in the mission file \item Configure the \app{uTimerScript} \end{packed_itemize} \vspace{0.1in} \noindent To enable \app{uTimerScript} to be launched, it needs to be added to the Antler configuration block in \var{alpha.moos}. Just add the last line as in the example below. \begin{fileverb} //------------------------------------------ // Antler configuration block ProcessConfig = ANTLER { MSBetweenLaunches = 200 Run = MOOSDB @ NewConsole = false Run = pLogger @ NewConsole = false Run = uSimMarineV22 @ NewConsole = false Run = pMarinePIDV22 @ NewConsole = false Run = pHelmIvP @ NewConsole = false Run = pMarineViewer @ NewConsole = false Run = uProcessWatch @ NewConsole = false Run = pNodeReporter @ NewConsole = false Run = uTimerScript @ NewConsole = false <-- Add this line (but not the comment) } \end{fileverb} \vspace{0.1in} \noindent The documentation for \app{uTimerScript} can be found at the below link: \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/apps/uTimerScript} \vspace{0.1in} \noindent Or on the command line with: \vspace{0.1in} \begin{consoleverb} $ uTimerScript --web \end{consoleverb} \vspace{0.1in} \vspace{0.1in} \noindent The configuration block should look like that below. You can copy it into your mission file, but try to understand the configuration parameters by reading the documentation. \vspace{0.1in} \begin{consoleverb} //------------------------------------------ // uTimerScript configuration block ProcessConfig = uTimerScript { AppTick = 4 CommsTick = 4 condition = DEPLOY = true randvar = varname=RND_DEPTH, min=20, max=80, key=at_reset event = var=DEPTH_UPDATE, val=depth=$[RND_DEPTH], time=120 reset_max = nolimit reset_time = all-posted } \end{consoleverb} \vspace{0.1in} \noindent The end result when properly working should look like below. Note the events being posted with random depth values in \app{uTimerScript}, and the subsequent depth changes in the simulation. \begin{figure}[H] \centering \includegraphics[width=0.94\textwidth]{figures/s11_alpha.png} \caption{The \var{s11\_alpha} mission in final working state.} \label{fig_s11_alpha} \gif{figures/s11_alpha.gif} \end{figure} %====================================================================== \newpage \subsection{Exercise 5 - Use the MaxDepth Behavior to Limit Depth} \label{sec_s12} In this exercise the goal is to extend the previous mission to include a MaxDepth behavior. This behavior will be used to make sure that the maximum command depth will be 50 meters, even though random depths between 20 and 80 meters will continue to be generated by the script. \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s11\_alpha} mission, naming it \var{s12\_alpha} \item Add a \var{MaxDepth} behavior to the behavior file, limiting the maximum commanded depth to be 50 meters \item Ensure the priority weight for this behavior is higher than the ConstantDepth behavior. \end{packed_itemize} \vspace{0.1in} \noindent The documentation for \app{MaxDepth} behavior can be found at the below link: \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/bhvs/MaxDepth} \vspace{0.1in} \noindent The configuration block should look like that below. You can copy it into your behavior file, but try to understand the configuration parameters by reading the documentation. \vspace{0.1in} \begin{fileverb} //---------------------------------------------- Behavior=BHV_MaxDepth { name = max_depth pwt = 200 condition = DEPLOY = true duration = no-time-limit max_depth = 50 basewidth = 0 } \end{fileverb} \vspace{0.1in} \noindent The end result when properly working should look like below. Note the vehicle depth remains about 50 meters or less even when the timer script has chosen a deeper value. \begin{figure}[H] \centering \includegraphics[width=0.92\textwidth]{figures/s12_alpha.png} \caption{The \var{s12\_alpha} mission in final working state.} \label{fig_s12_alpha} \gif{figures/s12_alpha.gif} \end{figure} %====================================================================== \newpage \subsection{Exercise 6 - Simulate Surfacing for GPS} \label{sec_s13} In this exercise the goal is to extend the \var{s9\_alpha} mission to have a loitering UUV periodically stop and float to the surface, and weight at the surface for a period of time (presumably to get a GPS fix). Two new behavior instances will be added. Both are Timer behaviors. These behavior do not produce any objective function, no influence over heading, speed or depth decisions. They simply use the built-in timer (duration) feature available to all behaviors, to periodically post end flags. \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s9\_alpha} mission, naming it \var{s13\_alpha} \item Add a \var{Timer} behavior to the behavior file. This behavior will be on when (a) the vehicle is deployed (\var{DEPLOY=true}), and when a GPS fix is not needed (\var{NEED\_GPS=false}). It will have duration of 200 seconds, and when it completes, it will declare that a GPS fix is needed (\var{NEED\_GPS=true}). \item Add a second \var{Timer} behavior to the behavior file. This behavior will be on when (a) the vehicle is deployed (\var{DEPLOY=true}), and when a GPS fix is needed (\var{NEED\_GPS=true}), and when the vehicle is still not yet at the surface (\var{NAV\_DEPTH < 2}). It will have duration of 30 seconds, and when it completes, it will declare that a GPS fix is not needed (\var{NEED\_GPS=false}). \item The behavior file will need to declare that initially a GPS fix is not needed (\var{initialize NEED\_GPS = false}). \end{packed_itemize} \vspace{0.1in} \noindent The documentation for \app{Timer} behavior can be found at the below link: \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/bhvs/Timer} \vspace{0.1in} \noindent The configuration block should look like that below. You can copy it into your behavior file, but try to understand the configuration parameters by reading the documentation. \vspace{0.1in} \begin{fileverb} //---------------------------------------------- Behavior=BHV_Timer { name = timer_need_gps pwt = 100 condition = DEPLOY = true condition = NEED_GPS = false perpetual = true endflag = NEED_GPS = true duration = 200 duration_idle_decay = false } \end{fileverb} \vspace{0.1in} \noindent As mentioned above, you will need a second timer behavior, to act as the timer when the vehicle is on the surface. It should run for 30 seconds, to simulate a vehicle acquiring a GPS fix. When it completes after 30 seconds the vehicle should once again dive. We leave it up to you to add this configuration block. \vspace{0.1in} \noindent The end result when properly working should look like below. Note the vehicle depth slowly returns to zero when the vehicle is stopped, relying on buoyancy to float to the surface. \begin{figure}[H] \centering \includegraphics[width=0.92\textwidth]{figures/s13_alpha.png} \caption{The \var{s13\_alpha} mission in final working state.} \label{fig_s13_alpha} \gif{figures/s13_alpha.gif} \end{figure} %====================================================================== \newpage \subsection{Exercise 7 - Add Simulated Drift to the Mission} \label{sec_s14} In this exercise the goal is to extend the \var{s13\_alpha} mission to have include simulated drift in the simulation \vspace{0.1in} \noindent You will need to do the following steps: \begin{packed_itemize} \item Copy the \var{s13\_alpha} mission, naming it \var{s14\_alpha} \item Add two buttons to the \app{pMarineViewer} configuration to turn drift on and off. Add a drift at of 0.3 m/sec at heading 45 degrees. \item Note the performance of the Loiter behavior under drift. \end{packed_itemize} \vspace{0.1in} \noindent The documentation for the \app{uSimMarineV22} MOOS App can be found at the below link. The relevant part for this exercise is the drift vector feature. (This is just FYI - no need to modify the simulator in this exercise) \vspace{0.1in} \noindent \urlx{http://oceanai.mit.edu/ivpman/apps/uSimMarineV22} \vspace{0.1in} \noindent The line in the \app{pMarineViewer} configuration block should look like that below. You can copy it into your behavior file, but try to understand the configuration parameters by reading the documentation. The last two lines are the key additions for this exercise. \vspace{0.1in} \begin{fileverb} button_one = DEPLOY # DEPLOY=true button_one = MOOS_MANUAL_OVERRIDE=false # RETURN=false button_two = RETURN # RETURN=true button_three = DRIFT_ON # DRIFT_VECTOR = 45,0.3 button_four = DRIFT_OFF # DRIFT_VECTOR = 0,0 \end{fileverb} \vspace{0.1in} \noindent The end result when properly working should look like below. The drift vector was set shortly into the mission, and note the vehicle drifting Northeast when it has stopped and is floating to the surface. \begin{figure}[H] \centering \includegraphics[width=0.92\textwidth]{figures/s14_alpha.png} \caption{The \var{s14\_alpha} mission in final working state.} \label{fig_s14_alpha} \gif{figures/s14_alpha.gif} \end{figure} %====================================================================== \newpage \section{Where to Find the Solutions} %====================================================================== All solutions can be dowloaded from the class server (after the end of the class): \vspace{0.1in} \noindent Exercise 1: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s8\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s8\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 2: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s9\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s9\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 3: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s10\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s10\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 4: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s11\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s11\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 5: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s12\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s12\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 6: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s13\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s13\_alpha/alpha.bhv} \end{packed_itemize} \vspace{0.1in} \noindent Exercise 7: \begin{packed_itemize} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s14\_alpha/alpha.moos} \item \urlx{https://oceanai.mit.edu/minicourse-pisa/missions/s14\_alpha/alpha.bhv} \end{packed_itemize} \end{document}