ModalAI Forum

@alex-kushleyev @eric-katzfey Apologies for the direct mention — I hope you don't mind.

I posted this question set about two weeks ago (and a related product question three weeks ago), but haven't heard back yet. We are preparing to purchase a Starling 2 Max (C29, with the PMD ToF) as an evaluation unit for an indoor GPS-denied inspection project, and just three answers would unblock our decision:

1. Can VOXL SLAM / VOA (with the dense PMD ToF on the C29 configuration) reliably handle very narrow corridors — around 300 mm width? Any references to pipe/industrial inspection use cases in similar tight spaces would be very helpful.
2. For repeated missions in the same indoor space, is voxl-mapper + AprilTag re-localization the recommended pattern to bound Open-VINS drift (no loop closure)?
3. What is the practical minimum illumination for reliable VIO with the tracking cameras — and do you recommend onboard IR/LED illumination for dim industrial interiors?

Even brief pointers to relevant docs would be greatly appreciated. Thank you for the great platform and documentation!

Hi ModalAI team,

Reposting here under VOXL Dev Kits (also asked in the VOXL Flight Deck sub-forum). A few technical questions for our indoor GPS-denied inspection PoC — a compact custom quadcopter (X4) airframe built around the VOXL 2 Mini.

[SLAM / autonomy]

• VOA performance in narrow (~300 mm) corridors — any pipe / industrial refs?
• Open-VINS is pure VIO (no loop closure) — for repeated long flights, is Mapper + AprilTag re-localization enough to bound drift?

[Precision landing]

• voxl-vision-hub provides AprilTag relocalization but notes it "does not yet support autonomous takeoff and landing." Is a fully automated AprilTag precision landing onto a charging dock achievable using the VOXL SDK alone (voxl-tag-detector / voxl-vision-hub + PX4 precision-land), without us writing our own landing logic? If so, what is the recommended setup? If some part still needs custom development, which part?

[Cameras / sensors]

• VOXL 2 Mini has 4 MIPI-CSI. Using 2 for VIO + 1 downward for precision landing = 3. Can a 4th camera (gimbal / thermal) be added, and how?
• For the downward precision-landing camera, is MSU-M0166 (AR0144 micro-coax) the right choice? Can that downward AR0144 be shared by both VIO and the voxl-tag-detector (AprilTag) at the same time?
• Recommended ToF module for collision avoidance?

[Airframe / drivetrain]

• Is VOXL ESC Mini (M0129) compatible with our own motor selection (DShot/PWM) in a standard quadcopter (X4) configuration?
• Any thermal / layout guidance for integrating VOXL 2 Mini + ESC Mini into a custom ducted-cage airframe?

[Mission / comms]

• Vision Hub: can an external host (our charging station) send trajectories and trigger auto takeoff / landing?
• WiFi 2.4 GHz stability indoors — recommended radio module?

Note: We don't have hardware yet (pre-purchase), so voxl-version / voxl-inspect-services / PX4 logs are not available at this stage.

Thanks!
JinHyeok Kim, Pablo Air

Gentle bump — it's been 5 days and this thread is still open with no reply. Would really appreciate any input from the ModalAI engineering team on the questions above (VOA/SLAM in narrow ~300 mm corridors, fully automated AprilTag precision landing via the VOXL SDK alone, and sharing the downward AR0144 between VIO and voxl-tag-detector). Even partial pointers would help a lot — we're evaluating the VOXL 2 Mini for a PoC and are ready to buy an evaluation unit. Thanks!

Hi ModalAI team,

We were directed here from the sales channel. A few technical questions for our indoor GPS-denied inspection PoC — a compact custom quadcopter (X4) airframe built around the VOXL 2 Mini.

[SLAM / autonomy]

• VOA performance in narrow (~300 mm) corridors — any pipe / industrial refs?
• Open-VINS is pure VIO (no loop closure) — for repeated long flights, is Mapper + AprilTag re-localization enough to bound drift?

[Precision landing]

• voxl-vision-hub provides AprilTag relocalization but notes it "does not yet support autonomous takeoff and landing." Is a fully automated AprilTag precision landing onto a charging dock achievable using the VOXL SDK alone (voxl-tag-detector / voxl-vision-hub + PX4 precision-land), without us writing our own landing logic? If so, what is the recommended setup? If some part still needs custom development, which part?

[Cameras / sensors]

• VOXL 2 Mini has 4 MIPI-CSI. Using 2 for VIO + 1 downward for precision landing = 3. Can a 4th camera (gimbal / thermal) be added, and how?
• For the downward precision-landing camera, is MSU-M0166 (AR0144 micro-coax) the right choice? Can that downward AR0144 be shared by both VIO and the voxl-tag-detector (AprilTag) at the same time?
• Recommended ToF module for collision avoidance?

[Airframe / drivetrain]

• Is VOXL ESC Mini (M0129) compatible with our own motor selection (DShot/PWM) in a standard quadcopter (X4) configuration?
• Any thermal / layout guidance for integrating VOXL 2 Mini + ESC Mini into a custom ducted-cage airframe?

[Mission / comms]

• Vision Hub: can an external host (our charging station) send trajectories and trigger auto takeoff / landing?
• WiFi 2.4 GHz stability indoors — recommended radio module?

Note: We don't have hardware yet (pre-purchase), so voxl-version / voxl-inspect-services / PX4 logs are not available at this stage.

Thanks!
JinHyeok Kim, Pablo Air

Hi team — just bumping this in case it slipped through. We're ready to buy one evaluation unit and would really appreciate a quick steer: can the Stinger Vision FPV run AUTONOMOUS VIO/SLAM + AprilTag precision landing, or would Starling 2 / Starling 2 Max be the better evaluation platform for the requirements above? I've also emailed sales@modalai.com in parallel, so whichever channel is easier works for us. Thanks!

Hi ModalAI team,

We're building a compact indoor autonomous inspection drone (PoC) and want to
buy ONE evaluation unit before designing our own airframe around the VOXL 2 Mini.
Could you recommend the best-fit product?

Application: GPS-denied indoor flight through ~300 mm corridors, with AprilTag
precision landing onto a self-charging dock.

Key requirements:

• Size <= 200 x 200 mm (300 mm corridors), weight <= 600 g
• Ducted / caged frame (4-motor prop protection)
• VOXL 2 Mini (PX4), VIO / SLAM autonomy
• AprilTag precision landing <= 0.15 m, ToF / VOA collision avoidance
• Flight time >= 10 min, NDAA-compliant

Stinger Vision FPV looks close — is it usable for AUTONOMOUS (non-FPV) flight
with VIO/SLAM + AprilTag landing? Or is Starling 2 / Starling 2 Max a better
evaluation platform?

Also: lead time / pricing for a single unit, and any export (EAR) considerations
for shipping to South Korea.

Thanks!
JinHyeok Kim, Pablo Air