Rotatable Trim Excitation Mechanism for Adjustable Test Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing trim excitation devices, such as those used for testing aeronautical parts, lack precision, are large, heavy, and cumbersome, with limited operating range and excitation characteristics.
Innovation Solution
A trim excitation device with a rotatable drive shaft and eccentric drive pin that transforms rotational movement into linear movement, featuring a guiding mechanism and transfer member that can rotate to various positions, allowing adjustable excitation amplitude and frequency, and a pivot arm with adjustable pivot axis for precise control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If existing trim excitation devices are used, then excitation function is provided, but the devices are large, heavy, and cumbersome with limited operating range
Solution Approach 1:
The guiding mechanism and transfer member are made rotatable about a rotation axis, allowing the drive channel axis to change orientation relative to the link member. This dynamic configuration enables the same device to provide different excitation characteristics (longitudinal vs. lateral movement) by simply rotating to different positions, thereby expanding operating range without increasing device weight or complexity.
Solution Approach 2:
The rotational position of the guiding mechanism and transfer member changes the geometric parameters of the mechanism. By rotating to different angular positions, the drive channel axis can be oriented at different angles relative to the link member's longitudinal direction, fundamentally changing the excitation characteristics from longitudinal to lateral movement and enabling adjustable excitation amplitude and frequency.
2Adaptability or versatility
If the guiding mechanism and transfer member are rotatable to various positions, then excitation characteristics become adjustable, but device complexity increases
Solution Approach 1:
The rotation function and the excitation transmission function are merged into a single integrated mechanism. The guiding mechanism and transfer member simultaneously perform both the guidance of the eccentric drive pin and the transmission of rotational motion. This merging avoids the need for separate rotation actuators and transmission mechanisms, thereby reducing overall device complexity while maintaining full adjustability of excitation characteristics.
Solution Approach 2:
The guiding mechanism and transfer member serve multiple functions: they guide the eccentric drive pin, transmit rotational motion, and enable adjustable excitation characteristics. This multi-functionality reduces the need for additional specialized components, thereby controlling device complexity while achieving versatile excitation control.
3Force
If the drive channel axis extends perpendicular to the link member, then maximum longitudinal excitation is achieved, but lateral movement is eliminated
Solution Approach 1:
The system transitions from a fixed geometric configuration to a dynamic one where the drive channel axis can rotate relative to the link member. By rotating the guiding mechanism and transfer member, the system can dynamically switch between providing maximum longitudinal excitation (when perpendicular) and enabling lateral movement (when parallel), thereby achieving both force optimization and directional control.
Solution Approach 2:
The rotational movement of the eccentric drive pin combined with the rotatable guiding mechanism creates periodic variation in the excitation characteristics. By controlling the rotational position, the system can periodically alternate between different excitation modes (longitudinal vs. lateral), enabling flexible control over the type and magnitude of excitation applied to the object.
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 provides lightweight, precise, and reliable excitation with a wide operating range, enabling adjustable excitation characteristics like frequency, amplitude, and trim, suitable for testing aeronautical parts with sinusoidal motion.
Implementation Method 1
an eccentric drive pin mounted eccentrically on said drive shaft, which eccentric drive pin engages a drive channel of a transfer member and is movable back and forth in said drive channel
Implementation Method 2
the guiding mechanism includes a spring assembly to which the transfer member is attached, and which only allows said back-and-forth movement of the transfer member
Data Source
Figure 1
Figure 2
Figure 3~6
AI summary
A trim excitation device comprises an eccentric drive pin that engages a drive channel of a transfer member and is movable back and forth in said drive channel in the direction of a drive channel axis. The transfer member is connected to a first end of a link member of which an opposite second end can be connected to an object to be excited. The link member defines a longitudinal direction extending between its first and second ends, wherein the transfer member by means of a guiding mechanism is movable back-and-forth in a direction substantially perpendicular to the drive channel axis. The guiding mechanism and transfer member are rotatable for assuming a desired rotational position between and including a first rotational position in which the drive channel axis extends substantially perpendicularly to the longitudinal direction of the link member and in which the transfer member by means of the guiding mechanism is movable back-and-forth substantially in the longitudinal direction of the link member, and a second rotational position in which the drive channel axis extends substantially in the longitudinal direction of the link member and in which the transfer member by means of the guiding mechanism is movable back-and-forth substantially perpendicularly to the longitudinal direction of the link member.