Parallel Platform Support Structure With Alternating Joints for Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing devices for holding, moving, and positioning workpieces and objects lack stability and flexibility under high force or pressure, and often suffer from instability due to free movement of limbs.
Innovation Solution
A device with alternating revolute and prismatic joints, where every other joint is prismatic and every other joint is revolute, providing a more robust and stable construction. This includes a first prismatic joint with a bearing carriage slidably attached to a rail arrangement, and telescopic second prismatic joints with support structures to prevent rotation and increase stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If free movement of legs is provided, then flexibility of the device is improved, but stability of the device deteriorates
Solution Approach 1:
The patent changes the kinematic parameters of the limb joints from all-revolute or all-prismatic to an alternating revolute-prismatic configuration. This parameter change constrains the movement degrees of freedom while maintaining adaptability, resolving the contradiction between flexibility and stability.
Solution Approach 2:
The patent introduces dynamic constraints through the alternating joint configuration that adapts the stability characteristics during operation. The prismatic joints provide linear constraints while revolute joints allow rotational freedom, creating a dynamically balanced system that maintains both flexibility and stability.
2Reliability
If multiple joints are provided in each limb, then stability and robustness are improved, but device complexity increases
Solution Approach 1:
The patent segments each limb into multiple sections with alternating joint types (prismatic and revolute) rather than using a single complex joint. This segmentation distributes the functional requirements across simpler, standardized joint components, improving reliability while managing complexity through modular design.
Solution Approach 2:
Instead of using complex universal joints or multiple actuators per limb, the patent inverts the approach by using passive alternating joints that derive stability from their geometric arrangement and kinematic constraints, reducing the need for active control complexity.
3Stability of the object's composition
If limbs are constrained to prevent free movement, then stability is improved, but flexibility and range of motion deteriorate
Solution Approach 1:
The patent carefully selects the parameters of the alternating joints (prismatic for linear constraint, revolute for rotational freedom) to achieve the optimal balance between stability and range of motion. The alternating configuration ensures that constraints are applied in complementary directions, maintaining stability without overly restricting movement capability.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The disclosure relates to a machine comprising; a fixed lower platform having a first connecting area; a movable upper platform having an operating area and a second connecting area; at least three limbs, each limb comprising a lower section, an upper section and an intermediate section between said lower section and said upper section; wherein each limb interconnects said fixed lower platform and said movable upper platform by joining said first connecting area and said second connecting area, wherein said lower section of each limb comprises a first part of a first prismatic joint, wherein, the first connecting area comprises a cooperating second part of said first prismatic joint; wherein said lower section of each limb further comprises a first revolute joint; wherein said intermediate section of each limb comprises a second prismatic joint, wherein said upper section of each limb comprises a second revolute joint; wherein each limb is pivotably movable relative to said movable upper platform; wherein each of said limbs comprise an actuation arrangement for moving the movable upper platform relative to the fixed lower platform.