Experimental Mode changes how your car handles gas and braking from conventional cruise control logic to an AI-driven approach where the driving model directly decides when to speed up, slow down, and stop. It's the feature that lets your car attempt to stop for red lights and stop signs, but it's labeled "alpha quality" because mistakes should be expected. Most FrogPilot drivers don't toggle it manually. Instead, they use Conditional Experimental Mode to switch in and out of it automatically based on road conditions.
The Big Idea
Experimental Mode lets the driving model's neural network make gas and braking decisions based on what the camera sees, rather than relying solely on traditional speed-tracking cruise control.
Your car's driving system has two fundamentally different ways to control its speed. Think of it like choosing between a seasoned taxi dispatcher and a student driver with exceptional eyesight.
The first approach, called Chill Mode (or standard driving), is the taxi dispatcher. It follows a set of well-tested rules: maintain the speed you set, keep a safe distance from the car ahead, and slow down when you're closing in too fast. It doesn't "see" traffic lights, stop signs, or anything else on the road. It just tracks your set speed and reacts to the vehicle ahead using radar and distance calculations. It's predictable, reliable, and well-tested. This is the Adaptive Cruise Control mode.
The second approach, Experimental Mode, is the student driver with exceptional eyesight. The camera-based driving model processes raw video from the road-facing camera and makes human-like driving decisions: braking for a red light it sees ahead, stopping at a stop sign, or slowing down as it reads the road scene. Your set speed becomes just an upper limit; the model may choose to drive slower based on what it perceives. This is the "blended" mode, where both the neural network and the traditional planner contribute to braking decisions. Specifically, the system takes the more cautious of the two: if either the traditional planner or the neural network says "brake harder," the car brakes harder. If either says "stop," the car stops.
This is powerful, but imperfect. The model can sometimes misinterpret shadows, bridge overpasses, or unusual road markings as reasons to brake. That's why it's called "alpha quality": it will make mistakes, and you must always be ready to take over.
Experimental Mode in FrogPilot is the same underlying openpilot feature. FrogPilot adds Conditional Experimental Mode on top of it, which automatically switches between these two approaches based on your driving conditions, so you get the best of both worlds without pressing any buttons.
💡 Tip: Not to be confused with the openpilot Longitudinal Control (Alpha) toggle, which enables openpilot's control over gas and braking on cars that don't have it by default. That toggle is a prerequisite for Experimental Mode, not the same thing.
Key Terms (Plain English)
Here's a quick reference for the terms used throughout this page.
| Term | What it means |
|---|---|
| Blended mode | The longitudinal planning mode used during Experimental Mode. Both the traditional planner and the AI driving model contribute to braking decisions, and the more conservative output wins. |
| Chill Mode | The standard driving state where speed control uses conventional Adaptive Cruise Control logic. Your car follows the vehicle ahead and maintains your set speed. |
| Conditional Experimental Mode | A FrogPilot feature that automatically activates and deactivates Experimental Mode based on conditions like speed, curves, navigation turns, and stop light predictions. |
| End-to-end | A driving approach where a single neural network goes directly from camera images to gas and braking decisions, rather than using separate systems for detection and planning. |
| Longitudinal planner | The component that decides when to accelerate and brake. In Chill Mode, it runs in "ACC" mode; in Experimental Mode, it runs in "blended" mode. |
| openpilot longitudinal | When openpilot directly controls gas and braking using its own software, rather than relying on your car's built-in cruise control. Required for Experimental Mode to exist. |
| Stock longitudinal | When your car's own factory cruise control handles gas and braking while openpilot only steers. Experimental Mode is not available in this configuration. |
Where You'll See It
Experimental Mode appears in two settings panels and on your driving screen.
Settings Panels
Experimental Mode itself is a toggle in the Settings → Toggles panel (the stock openpilot toggles, not the FrogPilot settings). You'll find it listed as "Experimental Mode" with an atom icon. This is where you manually enable or disable it.
On some cars, you'll also see the openpilot Longitudinal Control (Alpha) toggle directly above it. That toggle must be enabled first before Experimental Mode becomes available. If your car natively supports openpilot gas and brake control, you won't see this extra toggle at all.
FrogPilot's Conditional Experimental Mode is found under FrogPilot → Driving Controls → Gas / Brake → Conditional Experimental Mode. This builds directly on Experimental Mode and is the recommended way to use it.
On-Road Driving Screen
When Experimental Mode is active, you'll see several visual changes:
| Visual Element | Chill Mode | Experimental Mode |
|---|---|---|
| Driving path edges | Green (shade varies by theme) | Orange (#DA6F25) |
| Steering wheel button background | Black (#000000) | Orange (#DA6F25) |
| Steering wheel icon (stock theme) | Standard steering wheel | Atom icon |
| Driving camera | Standard road view | Switches to the wide-angle camera at low speeds to show more of the road |
If you have Conditional Experimental Mode's Status Widget enabled, a small icon also appears showing the current mode and what triggered the switch.
Offroad Home Screen
On the right side of the home screen (when your car is parked), you'll see either "CHILL MODE ON" or "EXPERIMENTAL MODE ON" depending on the current setting.
How It Works (High Level)
The system decides between two planning modes based on whether Experimental Mode is active, then picks the more cautious output of both planners.
The Two Planning Modes
When Experimental Mode is off (Chill Mode), the longitudinal planner runs in "ACC" (Adaptive Cruise Control) mode. It targets your set speed, follows the car ahead at a safe distance, and limits acceleration in turns. The driving model's camera-based predictions don't influence braking decisions. This is smooth, predictable, and well-tested.
When Experimental Mode is on, the planner runs in "blended" mode. In this mode, two separate acceleration targets are computed:
- The traditional planner's target (same as ACC mode)
- The driving model's end-to-end target (what the neural network thinks you should do based on camera input)
The system then takes the minimum (most cautious) of these two targets. If the traditional planner says "maintain speed" but the model says "brake for that red light," the car brakes. Similarly, if either system says "stop," the car stops. This means blended mode is always at least as cautious as standard mode, but adds the ability to react to visual cues like traffic lights and stop signs.
⚠️ Warning: The driving model doesn't explicitly detect traffic lights or stop signs. It makes end-to-end decisions from what the camera sees. This means it may sometimes brake when there's no clear reason, or fail to brake when you'd expect it to. Always be ready to intervene.
The Confirmation Gate
Before Experimental Mode can be activated (either manually or by tapping the on-screen steering wheel button), you must have acknowledged a confirmation dialog. This one-time confirmation persists across reboots, so you only need to do it once. Until you confirm, the on-screen button tap does nothing, and the car stays in Chill Mode.
How Conditional Experimental Mode Manages It
For most FrogPilot drivers, Conditional Experimental Mode (enabled by default) is the system that decides when Experimental Mode turns on and off. When Conditional Experimental Mode is active, it continuously evaluates conditions like your speed, whether you're approaching a curve, whether the driving model predicts a stop ahead, and more. When a condition matches, it activates Experimental Mode. When all conditions clear, it reverts to Chill Mode.
This means you get the reliability of Chill Mode on the highway and the intelligence of Experimental Mode in neighborhoods and at intersections, all without touching a button.
Compatibility: What Your Car Needs
Experimental Mode requires openpilot to have direct control over your car's gas and brakes (openpilot longitudinal). If your car relies on its own factory cruise control for speed management (stock longitudinal), the entire Chill Mode vs. Experimental Mode distinction doesn't exist for your setup.
Some cars have openpilot gas and brake control built in. Others need you to enable a special toggle called openpilot Longitudinal Control (Alpha) first. This alpha toggle is only visible if your specific car model supports it. On cars that don't support it, the toggle is hidden entirely, and if there's no other way to get openpilot longitudinal, Experimental Mode will be grayed out and unavailable.
You can also manually disable openpilot gas and brake control through the Disable openpilot Longitudinal Control setting in FrogPilot → Vehicle Settings → Vehicle Settings. If this is turned on, Experimental Mode and all features that depend on it (including Conditional Experimental Mode) become unavailable.
The hasLongitudinalControl() check that determines whether Experimental Mode is available works like this: if your car has experimental longitudinal available, it checks whether you've enabled that alpha toggle; otherwise, it checks if your car natively supports openpilot longitudinal. In both cases, it also verifies that you haven't manually disabled openpilot longitudinal.
Settings Specification
These are the key parameters that control Experimental Mode and its related features.
| Setting Name | Default | Tuning Level | Notes |
|---|---|---|---|
| Conditional Experimental Mode | On | Standard | FrogPilot feature that automatically manages Experimental Mode based on driving conditions. Found under FrogPilot → Driving Controls → Gas / Brake. Requires openpilot gas and brake control. |
| Experimental Mode | Off | Minimal | The main toggle in Settings → Toggles. Requires confirmation and openpilot gas and brake control. |
| Experimental Mode Confirmed | Off | Minimal | One-time confirmation gate. Must be acknowledged before Experimental Mode can be toggled. Persists across reboots. |
| FrogsGoMoo's Experimental Tune | Off | Advanced | GM-only. Experimental tune that adjusts stopping and takeoff parameters for smoother behavior on GM vehicles. Found under FrogPilot → Vehicle Settings → Vehicle Settings → General Motors Settings. |
| openpilot Longitudinal Control (Alpha) | Off | Minimal | Only visible on cars with experimental longitudinal available. Enables openpilot gas and brake control, which unlocks Experimental Mode. Part of an excluded set, meaning a normal settings reset won't clear it. |
| Predicted Stop In (CEModelStopTime) | 8 seconds | Developer | Controls how far ahead the driving model's stop prediction must be to trigger Experimental Mode through Conditional Experimental Mode. Range: 0 (Off) to 9 seconds. Lower values make the system more conservative (only reacting to imminent stops); higher values make it switch to Experimental Mode earlier. |
Predicted Stop In (CEModelStopTime)
| Property | Value |
|---|---|
| Default | 8 seconds |
| Range | 0 (Off) – 9 |
| Recommended | The default of 8 seconds works well for most drivers |
| Units | seconds |
This setting is part of Conditional Experimental Mode and determines how the driving model's stop predictions trigger a switch to Experimental Mode. At high values (7–9 seconds), the system switches to Experimental Mode well in advance of a predicted stop, giving the model more time to plan a smooth deceleration. At low values (1–3 seconds), it only switches when a stop is imminent. Setting it to 0 disables this trigger entirely.
At Standard and Advanced tuning levels, this setting appears as a simpler toggle called "Detected" Stop Lights/Signs (enabled by default), which uses the default 8-second value. At Developer tuning level, you get the full numeric slider. At Minimal tuning level, neither version is visible.
What this means for you: If your car brakes too early or too often for perceived stop lights, lower this value. If it doesn't switch to Experimental Mode soon enough before a red light, raise it.
FrogsGoMoo's Experimental Tune (ExperimentalGMTune)
| Property | Value |
|---|---|
| Default | Off |
| Recommended | On for GM owners who experience jerky stops or sluggish takeoffs |
This toggle is only available on General Motors vehicles (Chevrolet Bolt, Volt, etc.) with openpilot gas and brake control. When enabled, it overrides three specific stopping and takeoff parameters:
- Stopping rate is set to 0.3 (how quickly braking ramps up when stopping)
- Start speed is set to 0.15 (the speed at which openpilot exits the stopped state)
- Stop speed is set to 0.15 (the speed at which openpilot considers the vehicle stopped)
What this means for you: GM vehicles sometimes have jerky stopping behavior or sluggish takeoffs from a standstill. This tune attempts to smooth both out. If you're a GM owner and the default stopping behavior feels abrupt, try enabling this. Note that when this tune is active, the individual Start Speed, Stop Speed, and Stopping Rate sliders under Advanced Longitudinal Tuning are hidden since they're being overridden.
The "Excluded Keys" Behavior
The openpilot Longitudinal Control (Alpha) parameter is part of an excluded set, meaning that when you use FrogPilot's settings reset tools, this particular setting won't be affected. This is intentional: accidentally resetting this toggle could suddenly change how your car handles gas and braking, which would be dangerous if it happened while driving. Similarly, the system cleans up the parameter automatically on startup if your car doesn't support experimental longitudinal.
Driving Behavior: Experimental Mode On vs. Off
Here's what you'll notice in common driving scenarios.
| Scenario | Chill Mode (Off) | Experimental Mode (On) |
|---|---|---|
| Approaching a red light | No reaction. Maintains your set speed or follows the car ahead. You must brake yourself. | Attempts to slow down and stop. May brake smoothly or may brake late/hard depending on the model's confidence. Not guaranteed. |
| Approaching a stop sign | No reaction. You must brake yourself. | Attempts to slow down and stop. Detection is less reliable than for traffic lights. |
| City intersections | Drives through at your set speed unless a car ahead slows down. | Attempts to respond to the intersection. May slow or stop based on what the camera sees. |
| Construction zones | No special reaction beyond following the car ahead. | May be confused by unusual lane markings, cones, or temporary signs. Behavior can be unpredictable. |
| Curve handling | Limits acceleration in turns based on physics calculations. Doesn't proactively slow down for curves. | Similar behavior, plus the model may proactively slow if it "sees" the curve ahead in the camera view. |
| Cut-in by another vehicle | Reacts based on radar/distance tracking. Generally smooth and predictable. | Also reacts, but the blended approach may result in slightly different braking timing since both the traditional planner and the model contribute. |
| Highway cruising | Smooth and predictable. Tracks your set speed, follows the car ahead. | Can be slightly less predictable. The model might occasionally brake for shadows, overpasses, or distant objects it misinterprets. |
| Speed control | Your set speed is the target speed. The car tries to reach and maintain it. | Your set speed is only an upper limit. The model may choose to drive slower based on what it perceives. |
⚠️ Warning: Neither mode replaces driver attention. Chill Mode won't stop for traffic lights at all. Experimental Mode attempts to but isn't reliable. You must always be ready to brake yourself.
Relationship with Conditional Experimental Mode
Conditional Experimental Mode is the recommended way to use Experimental Mode for daily driving.
Conditional Experimental Mode (enabled by default, found at FrogPilot → Driving Controls → Gas / Brake → Conditional Experimental Mode) automatically activates Experimental Mode when certain conditions are met and reverts to Chill Mode when they clear. The dependency chain works like this:
- Your car must support openpilot gas and brake control (openpilot longitudinal)
- Experimental Mode must be available (confirmation acknowledged)
- Conditional Experimental Mode reads conditions like your speed, curve detection, navigation data, lead vehicle behavior, and the model's stop predictions
- When a condition triggers, Conditional Experimental Mode activates Experimental Mode
- When all conditions clear, it reverts to Chill Mode
When Conditional Experimental Mode is active, you shouldn't expect to stay in Experimental Mode 100% of the time. The whole point is that it's selective: using the AI-driven approach only when the situation calls for it and falling back to predictable cruise control for straightforward highway driving.
You can still manually override Conditional Experimental Mode by tapping the on-screen steering wheel button. This cycles through forced Chill Mode, forced Experimental Mode, and back to automatic control.
Limitations & Known Issues
Experimental Mode is an alpha-quality feature with real limitations you should understand before relying on it.
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The driving model doesn't explicitly detect traffic lights or stop signs. It makes end-to-end decisions from camera input. This means it can "stop" for something that looks like a stop situation but isn't, or fail to stop when you'd expect it to. Shadows on the road, bridge overpasses, reflective signs, and unusual road geometry can all confuse it.
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Construction zones are particularly challenging. Temporary lane markings, cones, flaggers, and shifted lanes create visual patterns the model wasn't trained on extensively. Expect unpredictable behavior in active construction areas.
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Different driving models behave differently. The specific driving model you have installed affects how aggressively Experimental Mode brakes, how early it detects stops, and how smooth its decisions are. Switching models may noticeably change the Experimental Mode experience.
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Highway driving can be slightly less smooth. The model occasionally brakes for distant objects it misinterprets as threats. For long highway stretches with no traffic lights, Chill Mode typically provides a smoother experience, which is exactly why Conditional Experimental Mode automatically reverts to it at highway speeds.
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Cars without openpilot gas and brake control can't use it. If your car relies on its factory cruise control for speed, Experimental Mode is not available. The toggle will be grayed out and disabled in settings.
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Night driving and adverse weather reduce reliability. The driving model relies on camera input. Poor lighting, rain, snow, or sun glare directly impact its ability to interpret the road scene. Be especially vigilant in these conditions.
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The model can phantom brake. Occasionally, the model will brake when there's no apparent reason. Common causes include shadows across the road, parked cars on the shoulder, and overhead signs or structures. This is a known characteristic of the alpha-quality feature.
Q: Experimental Mode is grayed out and I can't turn it on. What's wrong?
A: Your car likely doesn't support openpilot gas and brake control, which is required for Experimental Mode. Check the Vehicle Info section under FrogPilot → Vehicle Settings → Vehicle Settings to see if "openpilot Longitudinal Support" shows "Yes." If your car has the optional openpilot Longitudinal Control (Alpha) toggle visible in Settings → Toggles, you need to enable that first. If neither option is available, your car uses its factory cruise control for speed, and the Chill Mode vs. Experimental Mode distinction doesn't apply.
Q: Can I use Experimental Mode without Conditional Experimental Mode?
A: Yes. You can disable Conditional Experimental Mode entirely and manually toggle Experimental Mode on or off through the Settings → Toggles panel or by tapping the on-screen steering wheel button while driving. In this manual mode, it stays in whichever state you set it to until you change it again. However, most drivers find Conditional Experimental Mode much more convenient because it handles the switching automatically.
Q: Does Experimental Mode work without maps or navigation?
A: Yes. Experimental Mode itself doesn't need maps or navigation at all. It relies solely on the camera-based driving model to make decisions. Maps and navigation are used by Conditional Experimental Mode to trigger mode switches (for example, switching to Experimental Mode when approaching a navigation turn), and by Speed Limit Controller for speed data. But the core Experimental Mode functionality, the model's ability to brake for what it sees in the camera, works independently of any map or navigation data.
Q: I'm a GM owner. Should I enable the FrogsGoMoo's Experimental Tune?
A: If you're experiencing jerky stops, rolling at standstills, or sluggish takeoffs from stopped positions, try enabling it. It specifically adjusts the stopping rate, start speed, and stop speed parameters to values that work better with GM vehicles' gas and brake response characteristics. It's labeled "experimental" because it's a community-developed tune, not a factory-calibrated setting. Start with it on and see if your daily driving feels smoother. If it doesn't improve things, you can simply turn it off.
Q: I see "Experimental Mode" in my Toggles panel, but the car still drives like normal cruise control. It doesn't stop for lights.
A: Several things to check. First, confirm that Experimental Mode is actually toggled on (the toggle should be active, not just visible). Second, if Conditional Experimental Mode is enabled (it is by default), the system may be keeping you in Chill Mode because no trigger conditions are met. Look for the status widget on your driving screen. If you see the chill mode icon with a black border, you're in Chill Mode. Third, make sure you've confirmed the Experimental Mode dialog. Until you do, the mode won't actually activate even if the toggle appears enabled.
Q: My car doesn't brake hard enough at stop lights. It stops late.
A: The driving model's stop predictions depend heavily on visibility. If the stop light is obscured, far away, or against a bright sky, the model may not react until late. You can increase the Predicted Stop In value (up to 9 seconds) so the system switches to Experimental Mode earlier when it detects any stop prediction. Also try enabling Force Stop at "Detected" Stop Lights/Signs under FrogPilot → Driving Controls → Gas / Brake → Quality of Life, which makes the system more assertive about stopping.
Q: My car brakes too hard at stop lights in Experimental Mode.
A: This is typically caused by the Predicted Stop In setting being too high, which triggers the mode switch early and gives the model a long prediction window. Try lowering it from the default of 8 seconds to 5 or 6 seconds. You'll need Developer tuning level to access the numeric slider directly; at Standard and Advanced tuning levels, you can disable the "Detected Stop Lights/Signs" toggle under Conditional Experimental Mode's settings to stop this trigger entirely. If you drive a GM vehicle, enabling FrogsGoMoo's Experimental Tune may also smooth out stopping behavior.
Q: My car phantom brakes at overpasses and shadows. Is this Experimental Mode?
A: Very likely. If you're using Conditional Experimental Mode, check the status widget on your driving screen when the phantom braking occurs. If the widget shows an orange border with an Experimental Mode icon, the AI driving model is making the braking decision based on what it sees (or thinks it sees) in the camera. Overpasses, shadows across the road, and parked vehicles on shoulders are common triggers. You can reduce this by lowering the Predicted Stop In value or adjusting which conditions trigger Experimental Mode in Conditional Experimental Mode's settings.
Q: Should I use Experimental Mode on the highway?
A: For most drivers, no. Highway driving is where Chill Mode shines: it's smooth, predictable, and doesn't have the occasional phantom braking that Experimental Mode can exhibit. The AI model adds the most value in city driving, where traffic lights, stop signs, and intersections exist. This is exactly why Conditional Experimental Mode is configured by default to use Chill Mode at higher speeds and only switch to Experimental Mode in lower-speed or more complex situations.
Q: What's the difference between Experimental Mode and Conditional Experimental Mode?
A: Experimental Mode is the underlying driving mode that lets the AI model control gas and braking. It's either on or off. Conditional Experimental Mode is a FrogPilot feature that automatically manages when Experimental Mode turns on and off based on your driving conditions. Think of Experimental Mode as the engine and Conditional Experimental Mode as the smart thermostat that decides when to turn it on. Most drivers should leave Conditional Experimental Mode enabled and let it handle the switching automatically.
Q: Experimental Mode keeps switching off on the highway.
A: This is Conditional Experimental Mode working as designed. It automatically reverts to Chill Mode when you're above its speed thresholds and no trigger conditions are met. Highway driving at steady speeds is exactly the scenario where Chill Mode works best. If you want to force Experimental Mode to stay on, you can tap the on-screen steering wheel button to manually override, or increase the speed thresholds in Conditional Experimental Mode's settings.
Related Features
Experimental Mode is the foundation that several FrogPilot features build upon or interact with.
| Feature | How it interacts | Relationship |
|---|---|---|
| Conditional Experimental Mode | Automatically activates and deactivates Experimental Mode based on speed, curves, navigation, lead vehicles, stop predictions, and other driving conditions. This is the recommended way to use Experimental Mode for daily driving. | Manages transitions |
| Curve Speed Controller | Adjusts your target speed for curves in both Chill Mode and Experimental Mode. When Conditional Experimental Mode detects a curve, it may switch to Experimental Mode for the model's input, while Curve Speed Controller independently sets a curve-appropriate speed. | Works alongside |
| Speed Limit Controller | When Speed Limit Controller can't find a speed limit and its fallback is set to "Experimental Mode," it triggers a switch to Experimental Mode through the conditional system (even if no other Conditional Experimental Mode trigger is active). | Can trigger activation |
