Dialogflow Driving Sphero Reliably

Yes - the most reliable pattern in ARC is to treat DialogFlow as an intent parser only, then have a small script layer do the movement in a controlled way.

Recommended approach

1) Use a numeric parameter, not @sys.duration

For timed motion, I recommend:

• @sys.number for the amount
• a separate entity or slot for the unit if you want "seconds" vs "milliseconds"

That avoids DialogFlow returning mixed strings like "2s" or "2.0 sec".

If you only care about seconds, just use @sys.number and interpret it as seconds in your ARC script.

2) Debounce duplicate DialogFlow responses

If the On Response script is firing twice, add a simple guard variable in ARC.

Example pattern:

var now = new Date().getTime();
var last = parseInt(getVar("$LastDialogFlowMs", "0"));

if ((now - last) < 400) {
  print("Ignoring duplicate DialogFlow response");
  return;
}

setVar("$LastDialogFlowMs", now.toString());

That will ignore repeats within 400 ms.
You can adjust the window if needed.

3) Move first, stop only once, and avoid extra stop calls

For Sphero, a clean sequence is:

• set speed
• start movement
• sleep for the requested time
• stop

If you’re seeing a jerk from a pre-stop, that’s usually because the robot is already moving and then gets interrupted. In most cases, it’s better to only stop once at the end unless you are intentionally canceling an in-progress command.

Example ARC script for DialogFlow response

This assumes:

• $APIIntent contains the intent name
• $APIComplete is true when fulfillment is complete
• $APIParameters[0] = direction
• $APIParameters[1] = number of seconds

var intent = getVar("$APIIntent");
var complete = getVar("$APIComplete");

if (intent != "move.direction.time") {
  return;
}

if (!complete) {
  print(getVar("$APIResponse"));
  return;
}

// Debounce duplicate callbacks
var now = new Date().getTime();
var last = parseInt(getVar("$LastDialogFlowMs", "0"));

if ((now - last) < 400) {
  print("Duplicate intent ignored");
  return;
}

setVar("$LastDialogFlowMs", now.toString());

var direction = getVar("$APIParameters[0]").toLowerCase();
var seconds = parseFloat(getVar("$APIParameters[1]"));

if (isNaN(seconds) || seconds <= 0) {
  print("Invalid time parameter");
  return;
}

var ms = Math.round(seconds * 1000);

print("Direction: " + direction + ", time: " + ms + "ms");

Movement.stop();
sleep(100);

if (direction == "forward") {
  Movement.forward();
} else if (direction == "reverse") {
  Movement.reverse();
} else if (direction == "left") {
  Movement.left();
} else if (direction == "right") {
  Movement.right();
} else {
  print("Unsupported direction: " + direction);
  Movement.stop();
  return;
}

sleep(ms);
Movement.stop();

For spin left / spin right

If you want "spin left for one second", I’d suggest making a separate intent like:

• spin.direction.time

Then map:

• "left" -> Movement.left()
• "right" -> Movement.right()

If your Sphero movement skill has a specific "spin" behavior exposed through its movement panel, use that command instead. Otherwise, the left/right turn logic above is usually the simplest ARC pattern.

About the latency

That 500-1500 ms round-trip is normal when you wait on the cloud intent result. A few ways to reduce the impact:

1. Use DialogFlow only to determine intent
2. Keep the Sphero motion logic entirely local in ARC
3. Avoid extra waits in the script
4. Use a short debounce window
5. If you need near-instant response, consider using Speech Recognition directly to script for the most common commands and reserve DialogFlow for more flexible phrases

That last option is often the best user experience:

• Speech Recognition for fast commands like forward/stop/left/right
• DialogFlow for more complex conversation or ambiguous phrases

Best practice for parsing parameters

If you want robust numeric parsing, do this:

var raw = getVar("$APIParameters[1]");
var seconds = parseFloat(raw);

If you ever do want to support strings like "2 sec" or "2.5 seconds", you can strip text first:

var raw = getVar("$APIParameters[1]").toLowerCase();
raw = raw.replace("seconds", "");
raw = raw.replace("second", "");
raw = raw.replace("sec", "");
raw = raw.trim();

var seconds = parseFloat(raw);

But again, @sys.number is cleaner.

ARC config tip

You can place this script in the DialogFlow skill’s config menu:

1. Open the kebab menu / three lines on the DialogFlow skill
2. Choose Config
3. Edit the Script to Execute On Response

That keeps the parsing and movement logic in one place.

Helpful references

• ControlCommand(): https://synthiam.com/Support/Programming/control-command
• DialogFlow skill: https://synthiam.com/Support/Skills/Artificial-Intelligence/DialogFlow?id=15882
• Sphero Movement Panel: https://synthiam.com/Support/Skills/Movement-Panels/Sphero-Movement-Panel?id=16124

My recommendation for your project

For reliability, I’d use this structure:

• Speech Recognition captures phrase
• ControlCommand("DialogFlow", "Send", phrase)
• DialogFlow returns only the intent/parameters
• ARC script:
  • debounces
  • validates intent
  • parses numeric seconds
  • issues one movement command
  • sleeps locally
  • stops once

If you want, I can help you write a clean DialogFlow intent handler for:

• forward for two seconds
• reverse for three seconds
• spin left for one second
• stop

with a single reusable ARC JavaScript script.