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    Strider

    Strider is the operator UI for wheeled mobile bases. With it you jog the base, watch its state and odometry, and send navigation goals. It works with every drive type that a mobile robot document (.sddm) can describe: differential drive, skid steer 4WD, mecanum 4WD, swerve 4WD and Ackermann.

    How Strider Works in a Station

    Two nodes are involved:

    Node Role
    sodero.mlc.<name> The mobile base controller. It turns body velocities into wheel commands for its gateway, integrates odometry, and keeps the speed and acceleration limits of its .sddm document. It has no UI of its own.
    sodero.strider Strider. It drives what its ports are connected to: mobile_base to the base controller (driving and status), localization to the localizer (the robot's position on the map) and navigation to the navigator (goals). 
    flowchart LR
    S["sodero.strider"] -- mobile_base --> M["sodero.mlc.jackal<br>jackal.sddm"]
    M -- servo_link --> G["sodero.actuator_gateway.jackal<br>jackal.gw"]
    S -. localization .-> L["sodero.icp_localizer"]
    S -. navigation .-> N["sodero.navigator"]

    1. Set Up the Nodes

    1. In the Station's Store, install sodero.actuator_gateway, sodero.mlc and sodero.strider (Apps and Packages).
    2. Add the gateway, the base controller and Strider. Connect the controller's servo_link to the gateway, and Strider's mobile_base to the base controller (Build the Graph).
    3. Upload the gateway's .gw and the controller's .sddm document (Documents and Settings).
    4. Set the gateway's Robot name and check the actuator mapping (Connect to the World).
    5. Run the World, go live, then start the gateway, the controller and Strider, in this order (Start and Monitor Nodes).

    2. Open Strider

    On the Live page, right-click the running sodero.strider node and choose Open … (Start and Monitor Nodes). Strider opens in a new tab. If its session expires, open it again from the node.

    3. Screen Layout

    The left rail has three pages: Status, Drive and Navigation. The top bar holds the actions of the current page and, on every page:

    Item Description
    Readiness pill The current state in one line, for example Manual Drive Ready or Servo Off. Click it for the checks: Connection, Mobile base, Servo, Localization, Navigation.
    System Log Events of this browser session, filtered by System, Drive, Navigation and Localization
    Motion Alarm Active alarms and recent errors
    E-STOP Software stop: cancels driving and the navigation goal and sets the wheel speeds to zero at once, with the servo still on. It latches until Clear E-Stop, which switches the base to Idle.
    Units m / m/s / deg or m / m/s / rad, for display only

    Status Page

    Card Contents
    Trajectory (Odometry View) The path driven since the last mode change, in the odometry frame
    Operation Status Ready, moving or idle, servo on or off, and faults or stops
    Base Status (Odometry) Mode, and X, Y, Theta, VX, VY, WZ
    Control Node Health Whether the base, the localizer and the navigator are reachable
    Drive Unit Status The drive template and, per wheel, the servo state, position, velocity and target velocity
    Recent Events The latest events; View All opens the System Log

    Watchdog Tripped while the base stands still in Twist mode is normal: no velocity command is arriving, so the base holds zero speed.

    4. Jog the Base

    On the Drive page:

    1. Under Drive Mode, click Twist.
    2. Under Servo / Safety, switch Servo On. The readiness pill shows Manual Drive Ready.
    3. Set the Linear Velocity Limit (0.2 m/s by default, at most 0.8 m/s) and the Angular Velocity Limit.
    4. Press and hold a pad button: Forward (W), Backward (S), Turn Left (A) or Turn Right (D). The base moves while you hold the button and stops when you release it; Stop (Space) stops it too.
    5. To drive with the keyboard, switch on Live in Manual Drive, then use W, S, A, D and Space. Commands stop when the window loses focus.
    6. When you are done, switch the servo off and click Idle.
    Control Meaning
    Drive Mode Idle: no motion. Twist: body velocity commands, for jogging and navigation. Wheel: direct wheel speeds (advanced). EMG: stops the base like E-STOP, without latching.
    Servo On / Off Enables or disables the drives. Fault Reset clears drive faults; then switch the servo off and on again.
    Stop Motion Stops manual driving and cancels a navigation goal

    Manual commands take priority over navigation: jogging during a navigation goal overrides the navigator and can end the goal. A manual command expires after about a second, so the base stops if the connection drops. A navigation goal does not expire: cancel it with Stop Motion, Cancel or E-STOP.

    Show next to Advanced Controls opens Wheel Direct (each wheel's speed in Wheel mode), Preview Command (the wheel speeds a body velocity would give, without moving), Steering Origin, Calibration and Record / Replay.

    5. Navigation Page

    The Navigation page works when Strider's localization and navigation ports are connected to a running localizer and navigator, and the Station has a map bundle. To set them up, install sodero.icp_localizer and sodero.navigator from the Store, connect the localizer's camera port to the robot's camera gateway and the navigator's mobile_base and localization ports to the base controller and the localizer, and upload the map bundle (Build the Graph › Common Connections, Documents and Settings).

    Card Contents
    Navigation Map (Occupancy Grid) The map, the robot, the planned path and the goal. Drag to pan, scroll to zoom.
    Localization Status Healthy, Degraded, Initializing, Relocalizing, Lost or Uninitialized. Global localization searches the whole map.
    Mission Status, Current Pose (Map), Goal Pose, Route Summary The goal, where the robot is and how far it still has to go
    Navigator The navigator's state and a Speed Limit slider (10–100 %)
    Navigation Controls Set Initial Pose, Set Goal, Clear Goal, Pause, Resume, Cancel

    Set the Initial Pose

    If the localization status is not Healthy:

    1. Click Set Initial Pose.
    2. Press on the map where the robot stands and drag in the direction it faces.
    3. Click Set initial pose (or Relocalize here when a pose was set before).

    Send a Goal

    1. Make sure the base is in Twist with the servo on: the readiness pill shows Navigation Ready.
    2. Click Set Goal, press on the map where the robot should go and drag in the direction it should face.
    3. Click Start Navigation. The planned path appears.

    Pause cancels the goal and keeps it; Resume sends it again. Cancel stops navigation.

    6. Control Strider from Programs

    • AI agents drive the base with the station.strider tools: state, servo, velocities, stops and fault reset (AI Agents).
    • Your own module on the Station connects to the base controller's mobile_base port (Apps and Packages).
    • Your own tools on your computer reach the Station API through the Project VPN.