# How Farm Machines Automatically Adjust Height Over Uneven Ground

> This patent describes a system for farm equipment, like sprayers, to automatically keep their working parts at a precise, even height above the ground by using stored maps of the field and multiple motion sensors.

- **Patent:** US 9781915
- **Original title:** Implement and boom height control system and method
- **Owner:** Agjunction
- **Granted:** 2017
- **Status:** Active
- **Times cited:** 1
- **Field:** agriculture, software, telecommunications, mechanical, robotics

## What it does

The system first "stores field terrain elevation data" (Claim 1) for a specific work area. A user then selects a "desired height" (Claim 1) for the machine's working part, such as a sprayer boom, above the ground. As the machine moves, it "receives inertial movement data from multiple inertial measurement units (IMU) located on different sections" of the working component (Claim 1). These IMUs track the component's position. A computer then "compares the sensor data with the field terrain elevation data" (Claim 1). Based on this comparison and the desired height, the system "adjusts heights of the different sections of the working component" (Claim 1), for example, using an "electro-hydraulic mechanism" (Claim 7), to maintain the correct distance from the ground. The system can also use "global navigation satellite system (GNSS) measurements" (Claim 5) as part of its sensor data for enhanced accuracy. For example, a large crop sprayer driving over a bumpy field uses this system to ensure its spray nozzles stay exactly 20 inches above the plant canopy, preventing over-spraying or under-spraying.

## What it does NOT cover

- Does not cover systems that adjust the height of a working component without first "storing field terrain elevation data" (Claim 1).
- Does not cover systems that rely on only a single "inertial measurement unit (IMU)" for height control (Claim 1 specifies "multiple inertial measurement units (IMU) located on different sections").
- Does not cover systems that only adjust the overall height of the working component uniformly, rather than "adjusting heights of the different sections" independently (Claim 1).
- Does not cover systems that exclusively use non-inertial sensors (like optical or ultrasonic) without also incorporating "inertial movement data" (Claim 1).

## The clever bit

The key innovation is combining pre-mapped terrain data with real-time motion sensor data from multiple points on a large implement. This allows for precise, independent height adjustments of different sections of the machine, ensuring an even working height even over highly uneven ground.

## Real-world examples

1. Automated boom height control on agricultural sprayers
2. Precision planting depth control on seeders
3. Automated tillage depth control on cultivators
4. Guidance systems for large agricultural machinery

## Why it matters

This technology is crucial for precision agriculture. By maintaining a consistent height, farm implements like sprayers apply chemicals more accurately, reducing waste and environmental impact. It also helps planting equipment place seeds at the correct depth, leading to better crop yields. This precision saves farmers money and improves efficiency.

## Frequently asked questions

### What does How Farm Machines Automatically Adjust Height Over Uneven Ground cover?

This patent describes a system for farm equipment, like sprayers, to automatically keep their working parts at a precise, even height above the ground by using stored maps of the field and multiple motion sensors.

### Who owns patent US 9781915?

Agjunction owns this patent, granted in 2017.

### When does this patent expire?

This patent is expected to expire on March 14, 2034, when the invention enters the public domain.

### What is patent US 9781915 cited by?

This patent has been cited by 1 later patents that build on its ideas.

### What problem does this patent solve?

This technology is crucial for precision agriculture. By maintaining a consistent height, farm implements like sprayers apply chemicals more accurately, reducing waste and environmental impact. It also helps planting equipment place seeds at the correct depth, leading to better crop yields. This precision saves farmers money and improves efficiency.

### What does this patent NOT cover?

Does not cover systems that adjust the height of a working component without first "storing field terrain elevation data" (Claim 1).

**Full plain-English explainer:** https://patentbrief.org/patent/us/9781915/implement-and-boom-height-control-system-and-method

**Original patent:** https://patents.google.com/patent/US9781915

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._