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MT-01P 10m Laser Rangefinder — User Manual

The MT-01P is a compact 10 m laser rangefinder for drones — the distance half of the MTF-01P without the optical-flow camera. It outputs over UART or I2C (switchable), speaks MAVLink, MSP and Micolink, and works with ArduPilot, PX4, INAV and FMT. Point it down for precise altitude hold and fixed-wing auto-landing, or sideways for obstacle detection — on I2C, ArduPilot can run several MT-01Ps at once for multi-direction avoidance.

MicoAir MT-01P 10m laser rangefinder module

Where to buy​

Rangefinder or optical flow — which do I need?

A rangefinder measures one thing: distance along its beam. Pointed down, it gives the flight controller a precise height above ground — that's rock-solid altitude hold and terrain following, but the aircraft can still drift sideways. Horizontal position hold without GPS additionally needs an optical-flow camera — that's the MTF-01P / MTF-02P family. Buy the MT-01P when you need distance only (altitude, landing, obstacle avoidance) and the flow sensors when you need GPS-free hovering.

Specifications​

ItemSpecification
Range0.02–10 m @ 90% reflectivity (1 klux) · 0.02–7 m @ 70 klux
Range accuracy4 cm (0.02–2 m) · 2% (>2 m)
Light sourceLaser, 808 nm
FOV1.5°
InterfaceLVTTL (3.3 V) UART, 115200 baud · switchable to I2C
Data rate800 / 400 / 200 / 100 / 50 (default) / 25 / 10 / 5 Hz
Supply5 V, ~100 mA average
Mounting / size / weight24.3 × 12 mm Φ2.5 holes · 33.2 × 20.8 × 16.8 mm · 8 g
Rated range is a lab number

10 m is measured against a 90%-reflectivity target in mild light (1 klux). Two things shrink it in the real world: bright sun (7 m at 70 klux) and dark or vegetated ground — dry grass and asphalt reflect far less than 90%. Indoors and over pavement you'll see close to spec; over dark ground in summer sun, plan conservatively and check your logs. Also note the data-rate trade-off: higher output rates shorten the usable range and add noise — the 50 Hz default is the right choice for flight controllers.

Dimensions​

  • Mounting holes: 24.3 × 12 mm, Φ2.5 mm
  • Module (with case): 33.2 × 20.8 × 16.8 mm, 8 g

MT-01P dimensions — 33.2 × 20.8 × 16.8 mm, 24.3 × 12 mm mounting holes

Interface & wiring​

MT-01P pinout — GND, 5V, RX, TX

Same 4-pin layout as the MTF family: GND, 5V, RX, TX. For UART, cross-connect as always — sensor TX → flight controller RX, sensor RX → flight controller TX. In I2C mode the same two signal pins become SCL / SDA (straight-through: SCL→SCL, SDA→SDA).

Protocols & the MicoAssistant tool​

In UART mode the MT-01P offers three protocols, switchable with MicoAir's MicoAssistant configuration software:

  • MAVLink (default) — ArduPilot and PX4. Most users never need to change anything.
  • MSP — INAV.
  • Micolink — FMT, or your own custom integration (protocol definition).

I2C mode is switched the same way (or order the I2C version). Two hard requirements:

  • ArduPilot 4.5.0 or newer only — PX4/INAV do not support the MT-01P over I2C.
  • The bus needs pull-up resistors. The module has none on board; the flight controller's I2C port normally provides them.
Configuring a module that's already in I2C mode

Once in I2C mode the sensor no longer talks serial, so MicoAssistant can't see it the normal way. The trick: connect your USB-TTL adapter to the PC first, open MicoAssistant and connect to the port at 115200 — then plug the MT-01P into the adapter. MicoAssistant will identify it. If plugging the sensor in resets the adapter, a large capacitor across the adapter's 5 V output usually cures it.

ArduPilot — UART setup​

Firmware 4.1.0 or newer. Wire the sensor to any spare UART (TELEM1/2 …), TX/RX crossed, and set:

SERIALn_BAUD     = 115
SERIALn_OPTIONS  = 1024   (Don't forward)
SERIALn_PROTOCOL = 1
   (n = the serial port you used)
RNGFND1_TYPE     = 10     (MAVLink)
   — reboot or refresh parameters —
RNGFND1_ORIENT   = 25     (Down — must match the module's own orientation setting; both default to Down)

Reboot; the Status tab in Mission Planner should now show a live rangefinder1 value.

Mission Planner status tab showing rangefinder1 distance from the MT-01P

ArduPilot — I2C setup (single or multiple sensors)​

Switch the module to IIC_NOOPLOOP interface mode in MicoAssistant (or buy the I2C version). The module's TOF_ID parameter sets its bus address: ID 0 → address 0x08, ID 1 → 0x09, and so on — give every module on the same bus a different ID.

Wire SCL→SCL, SDA→SDA, then in ArduPilot:

RNGFND1_TYPE   = 40      — reboot / refresh —
RNGFND1_ADDR   = 8       (module with TOF_ID 0)
RNGFND1_ORIENT = 25      (Down for altitude; 0 = Forward, 6 = Left … for avoidance)

A second sensor is just RNGFND2_TYPE 40, RNGFND2_ADDR 9 (its TOF_ID set to 1), and its own orientation. Both distances appear in the Status tab, and the Proximity view visualizes them around the aircraft:

Mission Planner Proximity view showing two MT-01P sensors facing Forward and Left

PX4 — UART setup​

PX4 1.14 and newer:

MAV_1_CONFIG    = TELEM n     — reboot —
MAV_1_MODE      = Normal
SER_TELn_BAUD   = 115200 8N1
EKF2_RNG_CTRL   = Enabled
EKF2_HGT_REF    = Range sensor

PX4 1.12–1.13: same MAV_1 / baud settings, then EKF2_RNG_AID = Range aid enable and EKF2_HGT_MODE = Range sensor.

Reboot and check QGroundControl's MAVLink Inspector for the DISTANCE_SENSOR message. The message rate shown in QGC is set by the flight controller and the link speed — it is not the sensor's data rate, so don't worry if it looks low.

FAQ​

No rangefinder data in the ground station?​

Check, in order: TX/RX actually crossed (UART mode); the right SERIALn_ port configured; module protocol matches the firmware (MicoAssistant shows it — should be mav_apm for ArduPilot/PX4); RNGFND1_ORIENT matches the module's orientation setting (both default Down — if either was changed, ArduPilot silently ignores the sensor).

Can it do terrain following?​

Yes — with the sensor facing down and configured as above, ArduPilot's surface tracking (RNGFND + altitude-hold modes) and PX4's range-height EKF reference both work. Keep the 10 m envelope and ground reflectivity in mind.

Does it work over water or glass?​

Poorly — like all single-point laser rangefinders. Still or clear water absorbs and refracts the 808 nm beam, and glass returns confusing reflections. Expect dropouts and don't rely on it as the sole height source over water.

Written and maintained by the Robofusion engineering team.