Servo Recorder Repeatability On Adventurebot

Servo Recorder can replay servo motion, but for an AdventureBot with continuous-rotation drive servos, it’s usually not the best tool for repeatable drive paths.

What you’re seeing

A few things are happening here:

• Servo Recorder is position-focused, not motion-odometry focused.
• With continuous rotation servos, ARC is recording the servo command values over time, not the robot’s actual traveled path.
• So if battery voltage, floor friction, trim, WiFi latency, or the servo’s deadband changes, the same recording can drift.
• The speed modifier changes playback timing, but it can also make the motion feel "different" because the servo command pattern is still being played as a sequence of values over time.
• Reverse playback on CR servos is not a true "mirror the path" operation. It reverses the command sequence, which often produces very different robot motion than retracing a path.
• Starting two separate recordings from script can absolutely cause sync drift if they aren’t driven from one coordinated source.

Bottom line

For repeatable drive patterns on AdventureBot, I would recommend:

1. Movement Panel + scripted movement

   • Best if you want a repeatable forward/turn sequence.
   • Good for path-style routines.
   • Easier to tune and debug.

2. A JavaScript or Python timed script using Servo.setPosition()

   • Best if you want precise control over both wheels.
   • More reliable than servo Recorder for drive choreography.
   • You can explicitly set both wheel commands at the same time.

3. Servo Recorder

   • Better for arm gestures, head motions, poses, and animations
   • Not ideal for drive-path repeatability on continuous-rotation wheels

Why servo Recorder is a weak fit here

Servo Recorder is great when the output servo motion is:

• positional
• repeatable by angle
• not dependent on external physics

A drive base is different because:

• the robot’s actual motion depends on the floor
• wheel slip changes the path
• CR servos don’t report true position like smart servos
• "same command" does not equal "same path"

Better approach for your use case

If your goal is something like a repeatable figure-8, I’d suggest a scripted drive routine instead of recording.

For example, in JavaScript:

// Example: coordinated drive sequence for AdventureBot CR servos
// Adjust these values to match your robot's true stop/forward/reverse trim.

function drive(left, right, ms) {
  Servo.setPosition(d0, left);
  Servo.setPosition(d1, right);
  sleep(ms);
}

function stop(ms) {
  drive(90, 90, ms);
}

// Figure-8 style example
drive(120, 120, 1200);  // forward
drive(120, 100, 700);   // curve right
drive(120, 120, 1200);  // forward
drive(100, 120, 700);   // curve left
stop(300);

If your bot uses different port mapping or reversed wheel directions, the numeric values may need to be inverted.

For perfect sync

If you want both wheels to change at the same instant, the best practice is:

• set both servos in the same script
• avoid starting separate recorded clips independently
• use one function that updates both wheel ports together

That gives you much tighter synchronization than two separate playback commands.

One more important note

Because AdventureBot’s wheel servos are continuous rotation, you may get better results by building your motion around:

• forward/reverse/turn timing
• not "replaying" a captured path

If you want, ARC’s Movement Panel approach can be combined with scripts so you can press a button or call commands and still keep the drive behavior organized.

Recommended ARC docs

• Servo controls overview: https://synthiam.com/Support/ARC-Overview/Servo-Controls
• Servo Recorder skill: https://synthiam.com/Support/Skills/Servo/Servo-Recorder?id=15963
• Create a robot skill if you ever want a custom drive recorder/player: https://synthiam.com/Support/Create-Robot-Skill/Overview
• ARC AI Assistant for rewriting drive scripts directly in ARC: https://synthiam.com/Products/AI-Assistant

My recommendation

For AdventureBot drive patterns, I’d switch to:

• Movement Panel if you want operator-style driving
• JavaScript timed servo scripting if you want repeatable autonomous motion

Servo Recorder is fine for testing, but I would not trust it for repeatable path driving on CR wheel servos.

If you want, I can help you write a clean AdventureBot JavaScript figure-8 routine for your exact servo directions and trim values.