Metal Detector Speed Compensation for Crop Harvesters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing agricultural machines, such as forage harvesters, face challenges in maintaining metal detector sensitivity during dynamic speed changes, leading to reduced detection of foreign bodies and potential damage, especially during startup or rapid speed changes.
Innovation Solution
A non-volatile speed memory stores compensation information linked to conveying speed, allowing for effective interference compensation and maintaining high sensitivity of the foreign body detector across varying speeds and accelerations, including startup and braking phases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sensitivity is reduced to prevent self-triggering during dynamic speed changes, then false detections are avoided, but smaller foreign bodies can no longer be detected
Solution Approach 1:
The system performs preliminary action by storing compensation values for different speed ranges in advance during a normalization phase. When dynamic speed changes occur, the pre-stored compensation values corresponding to the current speed range are immediately applied, eliminating the need to reduce sensitivity and allowing small foreign bodies to be detected even during acceleration or braking phases.
2Measurement precision
If compensation is performed using previous revolution values, then cyclic interference voltages are filtered at constant speed, but the method fails during dynamic speed changes
Solution Approach 1:
The system applies dynamics by dividing the operating speed range into multiple speed ranges and storing different compensation values for each range. During dynamic speed changes, the system dynamically selects the appropriate compensation values based on the current speed range, enabling accurate interference compensation across varying operating conditions rather than relying on a fixed constant-speed compensation method.
Solution Approach 2:
The system changes parameters by storing and applying different compensation values corresponding to different speed ranges. When the conveyor speed changes, the system switches to the compensation values appropriate for the new speed range, allowing the compensation mechanism to adapt to parameter changes in operating conditions rather than failing as in constant-speed methods.
3Reliability
If detector sensitivity is strongly reduced during startup phases, then self-triggering is prevented, but the machine becomes susceptible to metal damage
Solution Approach 1:
The system performs preliminary action by pre-storing compensation values for the startup speed range during normalization. During actual startup, these pre-prepared compensation values are immediately applied, allowing the detector to maintain high sensitivity and detect small foreign bodies without self-triggering, thereby preventing metal damage while ensuring detector stability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution ensures high operational reliability and consistent foreign body detection sensitivity, preventing damage by accurately compensating for interference at different speeds and accelerations, similar to constant speed conditions.
Implementation Method 1
a foreign body detector, in particular metal detector, for detecting foreign body information of a foreign body in the crop
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The machine has a conveyor for conveying harvested crops, and a foreign object detector i.e. metal detector, for detecting foreign body information of a foreign body i.e. metal element, in the harvested crops and superimposed interference information. A compensation unit for partial compensation of the interference information by compensation information stored in a compensation storage. The compensation storage is formed as a speed storage unit for storing the compensation information with conveying speed and/or rotational speed of the conveyor. An independent claim is also included for a method for operating an agricultural machine.