Force-Feedback Operation Control With Coil Pre-Excitation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional force sense imparting operation devices for working machines, such as cranes, suffer from low responsiveness due to high inductance in coil systems, which delays the transmission of a proper force sense to operators, potentially leading to excessive loads and inappropriate motions when operating under high load conditions.
Innovation Solution
A force sense imparting operation device that includes an operation member, a displacement detector, a load detector, a force sense generator with an excitation coil, and a current controller. The current controller supplies a preliminary current before actual control, increasing responsiveness by adjusting the excitation current based on detected load and displacement thresholds, ensuring timely and appropriate force sense feedback to operators.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a coil system with high inductance is used to impart a high force sense to the operator, then the force sense magnitude is improved, but the response time deteriorates due to larger response lag
Solution Approach 1:
The patent applies preliminary action by pre-charging the excitation coil with a first excitation current before the actuation device starts moving. This preliminary current establishes an initial magnetic flux in the coil, so that when the full excitation current is applied later, the magnetic flux changes more rapidly, reducing the response lag while maintaining the necessary force sense magnitude
2Force
If the excitation current is increased to improve force sense feedback, then the force sense magnitude is improved, but the response lag increases due to higher inductance
Solution Approach 1:
The controller supplies a preliminary excitation current to the coil before the actuation device begins motion, creating an advance magnetic flux. When the full excitation current is subsequently applied, the magnetic flux transition occurs more quickly, reducing the time loss while maintaining adequate force sense feedback through the higher current
3Force
If a high excitation current is supplied to the coil to provide adequate force sense, then the force sense magnitude is improved, but the initial response is delayed due to coil inductance
Solution Approach 1:
The system performs preliminary action by establishing a first excitation current in the coil before the actuation device starts moving. This advance current creates an initial magnetic flux that reduces the lag when the full excitation current is applied, ensuring that the force sense feedback occurs at the correct timing rather than being delayed by coil inductance
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
The device improves responsiveness by reducing the initial increase in excitation current, allowing for immediate adjustment of force sense according to load conditions, thereby enhancing operator control and reducing the risk of excessive loads or inappropriate motions.
Implementation Method 1
a force sense generator including an excitation coil to which an excitation current is supplied, and configured to generate resistance against a displacement of the operation member by the excitation current supplied to the excitation coil
Data Source
AI summary
A force sense imparting operation device that imparts a force sense in accordance with a load acting on an actuation device. The device includes an operation member, a displacement detector, a load detector, a force sense generator that imparts a force sense to an operator who operates the operation member, a current controller that performs an actual control and a preliminary control, the actual control increasing the force sense imparted by the force sense generator by increasing an excitation current in response to an increase in the load, the preliminary control supplying the excitation current to an excitation coil prior to the actual control, the excitation current supplied by the preliminary control being set to a preliminary current value lower than the excitation current supplied to the excitation coil under the actual control, and a current supplying portion that supplies the excitation current to the excitation coil.