MakerFocus TFmini-s Micro LiDAR Module Instruction Manual

1. Introduction

This manual provides detailed instructions for the proper setup, operation, and maintenance of the MakerFocus TFmini-s Micro LiDAR Module. The TFmini-s is a compact, single-point ranging module designed for various applications requiring precise distance measurement and obstacle avoidance.

The TFmini-s is an upgraded version of the TFmini, featuring a reduced dead zone of 10 cm and improved outdoor performance and accuracy across different reflectances. It is compatible with popular development platforms such as Pixhawk, Arduino, and Raspberry Pi.

2. Product Overview

The TFmini-s operates on the Time of Flight (ToF) principle, integrating unique optical and electrical designs to achieve stable, precise, high-sensitivity, and high-speed distance detection.

MakerFocus TFmini-s Micro LiDAR Module with connection cables

Figure 2.1: MakerFocus TFmini-s Micro LiDAR Module with included connection cables.

Key Features:

Upgraded Performance: Reduced dead zone to 10 cm, enhanced outdoor performance, and improved accuracy.
Compact Design: Low-cost, small-size, and low power consumption.
High Precision: Distance resolution of 1 cm, frame rate of 100 Hz.
Robust Operation: Ambient light immunity up to 70 Klux.
Versatile Compatibility: Supports UART and I2C communication interfaces, compatible with Pixhawk, Arduino, and Raspberry Pi.

Comparison table between TFmini and TFmini-S LiDAR modules, highlighting improvements in blind zone, accuracy, light source, photobiological safety, FOV, and communication interface.

Figure 2.2: Comparison of key specifications between TFmini and TFmini-S modules, highlighting the improvements in the TFmini-S such as reduced blind zone and I2C communication support.

3. Technical Specifications

Parameter	Specification
Measuring Range	0.1m - 12m (at 90% reflectivity)
Blind Zone	10 cm
Accuracy	±6cm (0.1-6m), ±1% (6m-12m)
Distance Resolution	1 cm
Frame Rate	100 Hz
Ambient Light Immunity	70 Klux
Central Wavelength	850 nm
Light Source	VCSEL
Photobiological Safety	Class 1 (IEC60825)
Communication Interface	UART (default), I2C (switchable)
Product Dimensions	1.18 x 1.18 x 1.18 inches (approx. 30 x 30 x 30 mm)
Weight	0.2 ounces (approx. 5.6 grams)

Detailed specifications of TFmini-S including blind zone, frame rate, distance resolution, operating range, photobiological safety, and accuracy.

Figure 3.1: Summary of TFmini-s technical specifications.

Dimensional drawing of the TFmini-s module with measurements in millimeters.

Figure 3.2: TFmini-s module dimensions.

4. Setup and Installation

4.1 Pinout Description

The TFmini-s module features a 4-pin connector for power and communication. Refer to the table and diagram below for pin assignments.

Pinout diagram for the TFmini-s module showing four pins: Black (GND), Red (+5V), White (RXD/SDA), Green (TXD/SCL).

Figure 4.1: TFmini-s Pinout Diagram.

NO.	Color	Function	Comment
1	Black	GND	Ground
2	Red	+5V	Power supply
3	White	RXD/SDA	Receiving Data (UART) / Serial Data Line (I2C)
4	Green	TXD/SCL	Transmitting Data (UART) / Serial Clock Line (I2C)

4.2 Connecting to Microcontrollers (Arduino/Raspberry Pi)

The TFmini-s module can be easily integrated with various microcontrollers. The default communication interface is UART. If I2C is required, the module needs to be switched to I2C mode (refer to the official documentation for specific commands or software tools).

Diagram showing TFmini-s connected to an Arduino Uno board and another image showing the TFmini-s connected to a red development board.

Figure 4.2: Example connections of TFmini-s to an Arduino board and another development board.

For UART communication, connect the TFmini-s pins to the corresponding UART pins on your microcontroller:

TFmini-s GND to Microcontroller GND
TFmini-s +5V to Microcontroller 5V (or compatible power supply)
TFmini-s RXD to Microcontroller TXD
TFmini-s TXD to Microcontroller RXD

For I2C communication (after switching the module to I2C mode):

TFmini-s GND to Microcontroller GND
TFmini-s +5V to Microcontroller 5V (or compatible power supply)
TFmini-s SDA to Microcontroller SDA
TFmini-s SCL to Microcontroller SCL

Ensure proper voltage levels are maintained. The TFmini-s typically operates at 5V.

5. Operation

5.1 Principle of Operation (Time of Flight)

The TFmini-s uses the Time of Flight (ToF) principle to measure distance. It emits a modulated light signal and calculates the distance to an object by measuring the time it takes for the light to travel to the object and return to the sensor.

Diagram illustrating the Time of Flight (ToF) principle with light pulses emitted and received by the sensor to calculate distance.

Figure 5.1: Time of Flight (ToF) principle.

5.2 Data Acquisition

Once connected, the TFmini-s continuously outputs distance data at a 100 Hz frame rate. This data can be read via the chosen communication interface (UART or I2C) using appropriate libraries or custom code on your microcontroller.

For advanced monitoring and configuration, dedicated software tools may be available from the manufacturer. These tools typically allow for real-time data visualization and parameter adjustments.

Screenshot of a software interface for the TFmini module, showing settings, a time line chart of distance over time, and real-time data readings.

Figure 5.2: Example of a software interface for monitoring TFmini-s data.

5.3 Multi-Object Detection

The TFmini-s is capable of detecting distances to multiple objects within its field of view, providing the distance to the closest object. For scenarios with objects at different distances, the sensor will report the distance to the nearest reflective surface.

Diagram illustrating distance measurement in the case of two objects at different distances, showing the sensor detecting the closer object (Dist1).

Figure 5.3: Distance measurement with multiple objects.

The minimum side length of effective detection varies with the detecting range:

Detecting Range	Minimum Side Length
1m	3.5cm
2m	7cm
3m	10.5cm
4m	14cm
5m	17.5cm
6m	21cm
7m	24.5cm
8m	28cm
9m	31.5cm
10m	35cm
11m	38.5cm
12m	42cm

6. Applications

The TFmini-s module is suitable for a wide range of applications due to its compact size, accuracy, and speed:

Pedestrian Detection: For robotics, smart homes, or security systems.
Vehicle Detection: In smart parking systems or traffic monitoring.
Intelligent Barrier Gates: For automated access control.
Altimeter: For drones and other aerial vehicles.
Robotics: Obstacle avoidance and navigation for autonomous robots.
Industrial Automation: Level sensing, object positioning.

TFmini-s module integrated into a drone for altitude sensing or obstacle avoidance.

TFmini-s module used in an intelligent barrier gate system.

TFmini-s module connected to a small display showing distance readings.

Figure 6.1: Examples of TFmini-s applications in drones, barrier gates, and with a display unit.

7. Troubleshooting

7.1 Common Issues and Solutions

No Data Output:
- Verify power supply connections (+5V and GND).
- Check communication wiring (RXD/TXD or SDA/SCL). Ensure correct cross-connection for UART (TFmini-s TXD to microcontroller RXD, TFmini-s RXD to microcontroller TXD).
- Confirm the correct communication protocol (UART or I2C) is selected and configured on both the TFmini-s and the microcontroller. The TFmini-s defaults to UART.
- Ensure the baud rate for UART communication matches (typically 115200 bps).
Inaccurate Readings:
- Ensure the target object is within the specified measuring range (0.1m to 12m).
- Check for obstructions in the sensor's field of view.
- Avoid highly reflective or highly absorptive surfaces if possible, as they can affect accuracy.
- Minimize strong ambient light sources directly hitting the sensor, although the TFmini-s has good immunity up to 70 Klux.
- Ensure the sensor is mounted stably and not vibrating.
Module Getting Hot:
- Verify the input voltage is within the specified range (typically 5V). Overvoltage can cause overheating.
- Ensure adequate ventilation around the module, especially during continuous operation.

8. Safety Information

The TFmini-s uses a Class 1 laser product (IEC60825). While generally safe under normal operating conditions, avoid direct exposure of the eye to the laser beam.
Do not disassemble the module. Disassembly may expose you to laser radiation or damage the device.
Operate the module within its specified voltage and temperature ranges to prevent damage.
Keep the optical lenses clean for optimal performance.

9. Maintenance

Cleaning: Gently clean the optical lenses with a soft, lint-free cloth. Avoid abrasive materials or harsh chemicals.
Storage: Store the module in a dry, dust-free environment at room temperature when not in use.
Firmware Updates: Check the manufacturer's official website for any available firmware updates that may improve performance or add features.

10. Warranty and Support

For warranty information and technical support, please refer to the official MakerFocus website or contact your retailer. Additional documentation, software examples, and community forums may also be available online to assist with integration and development.

The product description mentions: "User Manual and Document: Please get the link from Product guides and documents below." This indicates that further resources are available through the product's official channels.