Flexure-Mounted Robotic End Effector for Precise Drilling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing robotic systems for drilling perforations in acoustic structures, such as gas turbine engine inlets, face issues with spindle movement deviations and wear due to friction, leading to irregular holes and increased stress, and require the use of sliding parts that result in unwanted debris and weight gain.
Innovation Solution
A robotic end effector assembly with a spindle support plate coupled to a base plate via flexible flexure plates, which inhibits off-axis drilling motion and maintains spindle alignment using a linear actuator, eliminating the need for sliding parts and reducing wear and debris.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If robotic arms with sliding rails are used for drilling, then linear motion is achieved, but increased wear, debris production, and weight increase occur
Solution Approach 1:
The patent replaces traditional sliding mechanical rails with a robotic arm system that uses flexible coupling and software-controlled coordinate transformations to achieve precise linear drilling motion. This eliminates physical sliding contacts, thereby removing wear and debris generation while maintaining the required linear motion capability for accurate drilling operations.
Solution Approach 2:
The patent transforms the control approach by changing from mechanical constraint parameters (sliding rails) to software-based parameter transformations (coordinate systems and mathematical models). The robotic arm uses programmed motion parameters and coordinate transformations to simulate perfect linear drilling paths, eliminating the need for physical sliding guides and their associated wear problems.
2Productivity
If robotic arms with sliding parts are used for drilling, then drilling motion is achieved, but friction and stiction cause spindle movement deviations
Solution Approach 1:
The patent eliminates mechanical sliding connections between the robotic arm and drilling spindle by using a flexible coupling system with software-controlled motion compensation. The robotic controller uses coordinate transformations and mathematical models to calculate and correct for any deviations, ensuring the spindle maintains precise alignment with the drill path without relying on friction-based mechanical guides.
Solution Approach 2:
The patent introduces a software-based intermediary layer (controller with coordinate transformation algorithms) between the robotic arm motion and the drilling spindle. This intermediary calculates real-time corrections and compensates for any friction or stiction effects, maintaining precise spindle alignment without direct mechanical contact that would cause friction-based deviations.
3Adaptability or versatility
If sliding rails are used to allow linear motion, then robot movement flexibility is improved, but wear and debris increase over time
Solution Approach 1:
The patent replaces the mechanical sliding rail system with a fully roboticized motion system that uses software-controlled coordinate transformations to achieve linear drilling paths. This substitution eliminates all sliding contact surfaces, thereby completely preventing the generation of wear debris while maintaining the required motion flexibility and adaptability for various drilling configurations.
4Extent of automation
If robotic spindle drilling is used, then automation is achieved, but spindle movement causes off-axis drilling issues
Solution Approach 1:
The patent introduces a sophisticated software intermediary (controller with coordinate transformation algorithms) that acts as a mediator between the automated robotic arm and the drilling spindle. This intermediary continuously calculates and applies corrections to compensate for spindle movements, ensuring that even with automated robotic operation, the drill bit maintains precise alignment with the intended drill path and avoids off-axis drilling errors.
Solution Approach 2:
The patent implements a feedback mechanism where the controller continuously monitors the robotic arm position and calculates the required spindle orientation adjustments using coordinate transformations. This closed-loop approach with real-time feedback ensures that any automated robotic movements that might cause off-axis drilling are compensated for, maintaining high drill path accuracy throughout the automated process.
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 solution ensures straight and precise drilling operations, minimizing spindle movement and deviations, reducing stress and wear, and eliminating the need for sliding parts, thereby improving hole quality and reducing system weight and maintenance.
Implementation Method 1
two flexure plates, each comprised of a flexible material... The flexure plates maintain an alignment of the spindle along an axis of the spindle. The flexure plates also inhibit an off-axis spindle drilling motion
Data Source
Figure 1~2
Figure 3A~3B
Figure 4
AI summary
There is provided a robotic end effector assembly (70) having a base (72) configured to be connected to a robot (62). The base (72) includes a robot adapter (74) coupled to a base plate (140). The robotic end effector assembly (70) further has a spindle support plate (120) positioned substantially parallel with and coupled to the base plate (140), via two flexure members (160). The robotic end effector assembly (70) further has a spindle (90) disposed on the spindle support plate (120). The robotic end effector assembly (70) further has an actuator (200) coupled between the base plate (140) and the spindle support plate (120). The actuator (200) is configured to engage an actuator mount (212) attached to the spindle support plate (120), to displace the spindle support plate (120). The flexure members (160) inhibit an off-axis drilling motion (300), as the spindle support plate (120) is displaced.