Rotary Actuator Vibration Isolation with Asymmetric Scissors Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vibration isolation systems, particularly in vehicles like tractor-trailers, often fail to adequately isolate occupants from harsh road-induced vibrations due to inadequate suspension systems, leading to discomfort during long periods of travel.
Innovation Solution
An active vibration isolation system featuring a suspended platform supported by a scissors mechanism exoskeleton with unequal length main links and a rotary actuator that applies controlled forces directly between the platform and the base, minimizing the use of conventional transmission mechanisms to enhance stability and reduce backlash.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional transmission mechanisms are used in vibration isolation systems, then force can be transmitted from the actuator to the platform, but backlash and reduced stability occur
Solution Approach 1:
The patent removes conventional transmission mechanisms (gears, belts, linkages) from the system between the rotary actuator and the scissors mechanism. The actuator applies force directly to the scissors mechanism through its rotors, eliminating intermediate transmission components that cause backlash and reduce stability.
Solution Approach 2:
The scissors mechanism serves as a direct intermediary between the rotary actuator and the suspended platform. Instead of using complex transmission mechanisms, the scissors mechanism translates the rotational motion of the actuator directly into linear displacement of the platform, providing a simple and effective force transmission path.
2Ease of manufacture
If equal length main links are used in the scissors mechanism, then the structure is simpler to manufacture, but the links cannot pass through parallel during displacement
Solution Approach 1:
The patent employs main links of unequal lengths in the scissors mechanism. This asymmetric configuration allows the links to pass through a parallel position during the platform's travel range, enabling smoother motion and better control throughout the full displacement range while maintaining structural integrity.
3Device complexity
If passive or semi-active suspension is used, then the system is simpler and more reliable, but adequate vibration isolation cannot be achieved for harsh road conditions
Solution Approach 1:
The patent implements an active vibration isolation system where a rotary actuator dynamically adjusts the position of the suspended platform in real-time. The actuator responds to vibration disturbances by applying corrective forces, providing adaptive isolation performance that exceeds what passive or semi-active systems can achieve, while maintaining reasonable system complexity.
Data Source
Figure 1
Figure 2a
Figure 2b
AI summary
An active vibration isolation system for isolating a suspended platform from vibration input to the vibration isolation system base includes an exoskeleton which supports the suspended platform relative to the base. The exoskeleton includes first and second scissors mechanisms with main links of unequal length. The main links pass through a parallel condition as the suspended platform moves over its intended range of travel relative to the base. The vibration isolation system may include a rotary actuator and a drive mechanism separate from the exoskeleton for providing force output from the rotary actuator to the suspended platform. The rotary actuator may include inner and outer rotors which rotate relative to each other and may be free to rotate relative to the exoskeleton. The rotary actuator may be free to translate relative to the vibration isolation system base and the suspended platform.