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Introduction
As UAVs are increasingly used in agriculture, powerline inspection, mapping, logistics, and industrial monitoring, flight safety has become one of the most important design requirements. A drone does not only need to fly from one point to another; it must also detect obstacles, maintain a stable altitude, and operate reliably in complex environments.
For many UAV developers, a practical and effective solution is to combine obstacle avoidance radar with an altimeter radar. The obstacle avoidance radar helps the drone detect objects in front of or behind the aircraft, while the downward-facing altimeter radar measures the distance between the UAV and the ground.
ZLY Technology provides a complete radar solution for this type of UAV navigation system: the ZLYMR220 UAV obstacle avoidance radar and the ZLY-LDRA100 UAV altimeter radar.
Why UAVs Need Both Obstacle Avoidance and Altitude Measurement
In real-world flight environments, drones often face multiple challenges at the same time. For example, an agricultural drone may need to fly between trees, avoid branches, and maintain a stable spraying height above crops. A powerline inspection UAV may need to detect poles, cables, and tower structures while flying at a controlled distance from the ground.
If the UAV only has altitude measurement, it may still fail to detect obstacles in the flight path. If it only has obstacle avoidance, it may not maintain accurate low-altitude flight over uneven terrain. This is why a combined radar system is more suitable for professional UAV applications.
A recommended configuration is:
- Two obstacle avoidance radars installed at the front of the UAV
- Two obstacle avoidance radars installed at the rear of the UAV
- One altimeter radar installed under the UAV body
This layout allows the drone to detect obstacles in both forward and backward directions while also measuring ground distance in real time.
ZLYMR220 Obstacle Avoidance Radar for Safer Flight
The ZLYMR220 is a millimeter-wave radar sensor designed for UAV obstacle avoidance. It can detect obstacles in complex flight environments and provides a maximum detection range of up to 260 meters.
One key advantage of ZLYMR220 is its ability to track up to 40 targets simultaneously. It can detect both stationary and moving objects and output target distance, speed, and angle information. This makes it suitable for UAVs that need reliable environmental perception during autonomous or semi-autonomous flight.
For UAV manufacturers and system integrators, the compact size and lightweight design are also important. The ZLYMR220 measures 62 × 62 × 20 mm and weighs about 98 g including a 1m wiring harness, making it easier to integrate into different UAV platforms.
ZLY-LDRA100 Altimeter Radar for Stable Height Control
The ZLY-LDRA100 is a 24GHz UAV radar designed for altitude measurement. It provides a measuring range from 0.2m to 100m with ±0.1m ranging accuracy. This allows the UAV to obtain reliable ground distance data during low-altitude flight.
Compared with some traditional sensors, millimeter-wave radar performs better in harsh environments such as rain, snow, fog, dust, and water mist. This is especially valuable for agricultural drones, where spraying mist, dust, uneven terrain, and changing weather conditions may affect flight stability.
The LDRA100 is compact, lightweight, easy to integrate, and suitable for UAV/UAS platforms, helicopters, and small airships. With low power consumption and stable performance, it is a practical choice for professional UAV altitude control.
Customer Case: Agricultural UAV in Orchard Spraying
One agricultural UAV integrator needed to improve the safety of a spraying drone used in orchards. The drone often had to fly at low altitude between rows of fruit trees. During operation, the aircraft faced several risks: branches extending into the flight path, uneven ground, slopes, dust, and spraying mist.
The customer wanted a radar solution that could help the UAV detect obstacles and maintain a stable spraying height. After evaluating the flight scenario, a combined radar layout was recommended: four ZLYMR220 obstacle avoidance radars and one ZLY-LDRA100 altimeter radar.
Two ZLYMR220 radars were installed at the front of the UAV to detect branches, trunks, poles, and other obstacles in the forward direction. Another two ZLYMR220 radars were installed at the rear to support safer backward movement, turning, and return flight. One LDRA100 radar was installed under the UAV body to continuously measure the distance from the aircraft to the ground.
With this configuration, the UAV could receive obstacle information from the front and rear while also maintaining better height control over uneven orchard terrain. The system helped improve operational safety and made the drone more suitable for complex agricultural environments.
A Practical Radar Combination for Professional UAVs
For UAVs operating in open fields, orchards, industrial parks, inspection routes, or low-visibility environments, radar sensors provide reliable data support for safer navigation. The combination of ZLYMR220 and LDRA100 gives UAV developers a practical way to build a more complete perception system.
The ZLYMR220 focuses on obstacle detection, multi-target tracking, and distance/speed/angle output. The LDRA100 focuses on accurate altitude measurement and stable performance in harsh environments. Together, they help UAVs fly more safely, maintain better altitude, and adapt to more complex working conditions.
Conclusion
Building a safer UAV navigation system requires more than one sensor. By using obstacle avoidance radar for front and rear detection and an altimeter radar for downward height measurement, UAV manufacturers can greatly improve flight safety and operational reliability.
For applications such as agricultural spraying, powerline inspection, industrial UAVs, and autonomous drone platforms, ZLY Technology’s ZLYMR220 obstacle avoidance radar and ZLY-LDRA100 UAV altimeter radar provide a reliable and easy-to-integrate radar solution.
If you are developing a UAV platform and need a customized radar sensing solution, ZLY Technology can support your project with professional millimeter-wave radar products and integration advice.
