Rotary Actuator Sensor Ring for Glove-Independent Touch Panels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary actuator arrangements for capacitive touch panels are hindered by dependence on human body capacitance, which fails with thick gloves or non-conductive prostheses, and require solid metal bodies, limiting design flexibility and miniaturization.
Innovation Solution
A rotary actuator design featuring a sensor ring with alternating contact and insulating surfaces, coupled to a stator with a single contact point, allowing operation independent of human capacitance and enabling use of non-metallic materials, including plastic or wood, with a toroidal or hollow cylindrical shape for enhanced design flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional rotary actuator arrangements utilize human body capacitance for touch panel operation, then the system can function with standard capacitive sensing, but the operation fails when users wear thick gloves or non-conductive prostheses due to lack of electrical coupling
Solution Approach 1:
The patent introduces a sensor ring with alternating conductive and insulating segments as an intermediary between the rotary actuator and the capacitive touch panel. This sensor ring generates artificial capacitance variations that simulate human touch, eliminating dependence on human body capacitance. The sensor ring acts as a mediator that translates mechanical rotation into electrical signals that the touch panel can detect, regardless of what the user is wearing.
2Reliability
If the rotary actuator is designed with a solid metal body to provide sufficient capacitance for touch panel influence, then the touch panel can be reliably actuated, but this prevents compact design and limits material selection for the rotating control element
Solution Approach 1:
The patent segments the traditional solid metal body into a sensor ring with alternating conductive and insulating segments. This segmentation allows the rotary actuator to generate capacitance variations through rotational movement of the segmented structure, eliminating the need for a large solid metal body. The segmented design reduces the overall volume while maintaining the ability to influence the capacitive touch panel.
Solution Approach 2:
The patent changes the fundamental parameter from requiring high absolute capacitance (solid metal body) to generating capacitance variations through rotational movement of segmented structures. This parameter change allows the use of non-metallic materials and enables compact design while maintaining reliable touch panel actuation.
3Reliability
If the rotary actuator uses a solid metal body to ensure sufficient capacitance, then reliable touch panel operation is achieved, but the rotating control element cannot be manufactured from freely selectable materials such as plastic or wood
Solution Approach 1:
The sensor ring with alternating conductive and insulating segments serves as an intermediary that generates the necessary capacitance variations through rotational movement. This allows the outer rotating control element to be made from any material (plastic, wood, metal) without affecting the capacitive coupling, as the sensor ring handles the electrical function while the control element provides only mechanical rotation and user interface.
4Measurement precision
If multiple contact points are used on the touch panel for the rotary actuator, then more comprehensive sensing is achieved, but the detection surface experiences increased stress and the design becomes more complex
Solution Approach 1:
The patent uses periodic action by rotating the segmented sensor ring to periodically modulate the capacitance at a single contact point. As the conductive and insulating segments alternately pass under the contact point, they create periodic capacitance variations that encode rotational position information. This approach achieves comprehensive sensing with minimal stress on the detection surface.
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
Enables reliable operation with any gloves or non-conductive prostheses, allows for small turntable designs, and facilitates the use of various materials, while minimizing stress on the touch panel and optimizing touchscreen utilization.
Implementation Method 1
a capacitively sensing detection surface (31), which has a sensor arrangement of the "mutual capacitance touch sensor" type
Implementation Method 2
the position changes of which generate variable electrical signals at the at least one contact point, which can be detected by the touch panel
Data Source
Figure 1
Figure 2~3
Figure 4~5B
AI summary
The invention relates to a rotary actuator assembly comprising a rotary actuator situated on a capacitively sensing detection surface of a touch panel, wherein the rotary actuator comprises a stator that forms at least one electrical contact point which abuts a fixed position of the detection surface, wherein a rotary body is rotatably mounted on the stator and is coupled to a sensor ring that can be rotated counter to the stator, the position changes of which sensor ring generate variable electrical signals at the at least one contact point, which signals can be detected by the touch panel, wherein the sensor ring alternately comprises, on a first ring surface over the circumference thereof, contact surfaces and insulating surfaces which can be contacted by at least one contact spring that is fixed on the stator, and wherein the at least one contact spring is in each case electrically connected to a contact point, wherein the touch panel comprises a "mutual capacitance touch sensor" assembly, and wherein the sensor ring comprises, on a second ring surface, a circumferential metal surface that is electrically connected to the contact surfaces of the first ring surface.