In modern agriculture, accurate seed singulation and population counting are vital to achieving high crop yields and avoiding the significant cost penalties of missed seeds (skips), multiple seeds (doubles), and population errors. ROJ integrates edge AI directly into the seed metering unit with its Vision4Seeding platform, using the STM32N6 MCU to detect seed status in real time at 38 inferences per second. Operators get automated visibility on every row, with no cloud dependency.
Application domains:
- Precision seed planting
- Smart farming and AgTech
- Agricultural machinery (OEM and retrofit)
Approach
As farms grow larger and the variety of crops increases, the whole industry shares the need for more precise seed planters. Accurate singulation, meaning exactly one seed placed at each position, directly impacts crop yield and farm economics.
Traditional solutions struggle to meet these demands, especially in multi-row, high-speed operations with diverse seed types. On planters with over 40 rows and discs spinning at 30 to 40 rpm, the task becomes significantly more complex. Seed sensors on tubes fail with small or irregular seeds and often miss or double-count. Cameras on seeding discs often deliver low-resolution or blurred images at high seeding speeds, and still rely on the operator's eye and manual adjustments. Both approaches fall short of the precision modern agriculture requires.
Vision4Seeding changes this by integrating edge AI directly into the metering unit. Machine vision algorithms running on the STM32N6 continuously analyze high-speed camera feeds from each planter row, detecting skips and doubles and counting seeds in real time.
Key benefits of this edge AI approach:
- Automated real-time monitoring: AI continuously detects planting errors, so operators no longer need to watch camera feeds
- High precision and consistency: Errors are detected even at higher RPM, independent of lighting and operator fatigue
- No cloud dependency: Inference runs on the device, minimizing latency and network requirements
- Bandwidth-efficient: Only relevant snapshots and compact inference results are sent to the operator interface
- OEM and retrofit compatible: A flexible path for both new and existing machinery
Application overview
The Vision4Seeding system integrates a global shutter camera with dedicated illumination, mounted directly on the metering unit.
1. Synchronized image capture
Each cycle begins with a synchronization signal from the seeding disc, which triggers image capture so that the new seeds are in frame.
2. Real-time edge inference
Snapshots are processed in real time by an optimized neural network on the STM32N6, accurately detecting seeds, skips, and doubles even at high speeds and across diverse seed types.
3. Result transmission and monitoring
Snapshots are compressed to JPEG and sent, together with the inference results, via Ethernet to the operator interface for centralized monitoring of multi-row planters. Sending only relevant images and compact inference data ensures precise visibility while minimizing bandwidth usage.
“
Powered by the STM32N6 MCU's advanced AI acceleration, Vision4Seeding gives the operator a superpower: AI now sees every seed status in real time. No more staring at camera feeds. With high-performance, low-latency inference at the edge, operators can focus on driving while Vision4Seeding guarantees perfect singulation.
”
Luca Bagatin, R&D Manager at ROJ
Technical details
Vision4Seeding relies on the AI acceleration of the STM32N6 (Neural-ART NPU) to run object detection on every capture cycle. With an inference time of 26 ms, the system sustains 38.4 inferences per second, keeping pace with high-speed planting operations where the disc spins rapidly and image capture must stay synchronized with disc rotation.
Sensor
Global shutter color sensor: VD66GY
The VD66GY captures sharp, coherent color images at high speed, avoiding motion distortion even when the seeding disc is spinning rapidly. This ensures reliable input for the detection model across operating speeds.
Model and results
Model:
- Object detection (seeds, skips, doubles)
- Architecture: ROJ custom lightweight neural network for seed detection
- Parameters: 0.99 M
- Input size: 320 × 320 × 3
Results:
- Weights (Flash): 943.25 KB
- Activations (RAM): 1.848 MB
- Inference time: 26 ms
- Inferences per second: 38.4
- Object detection mAP@0.5 (on board): 0.859
Software tools
- STM32Cube AI Studio, for neural network conversion and deployment
- ST Edge AI Core command-line interface
- STM32CubeIDE, for application development and debugging
- STM32CubeProgrammer, for flashing the artifacts to the target
Documentation
Resources
Optimized with STM32Cube AI Studio
STM32Cube AI Studio is a desktop tool designed to evaluate, optimize and compile neural network models for STM32 microcontrollers. It fully supports compilation for the Neural-ART Accelerator neural processing unit (NPU). It replaces the X-CUBE-AI in the ST AI product offering to cover new STM32 devices.
Most suitable for STM32N6 Series
The STM32 family of 32-bit microcontrollers based on the Arm Cortex®-M processor is designed to offer new degrees of freedom to MCU users. It offers products combining very high performance, real-time capabilities, digital signal processing, low-power / low-voltage operation, and connectivity, while maintaining full integration and ease of development.