Definition of Tactile sensing
센싱 원리 relates to mapping contact pressures across a surface, often across complex surfaces like the hand, head, and other human body parts.
The more often-used terms "압력 (Pressure)" and "힘 (Force)" are related to "촉각 (Tactile)," but both cannot capture the full complexity of contact mechanics. "Pressure" is a scalar value capturing solely magnitude and "force" is a vector expressing magnitude and direction.
Tactile measurement goes beyond by portraying the magnitude and distribution of contact pressures between two objects over an area as a matrix.
압력 (Pressure)
무지향성 스칼라(Omnidirectional Scalar)
힘 (Force)
지향성 백터(One Direction Vector)
촉각 (Tactile)
다중 DOF(Depth of Field) 표면
How does tactile sensing Work?
Tactile sensing is the technology of mapping and measuring the contact mechanics between two objects. Tactile sensing is closely related to pressure and force.
If you are searching for pressure measurement and mapping solutions, there are two main types of sensors: capacitance-based or resistance-based (piezoresistive sensors). Whereas resistive sensors work by measuring changes in the resistance of a semi-conductive materials, capacitive sensors work by measuring changes in the gap distance between two electrodes.
To function, the semi-conductive inks on a resistive sensor must go from a non-contacting state to a contacting state so the sensor performance is poor at low pressures. As the electrodes contact and rub against one another, the surface properties change on a microscopic level, which also changes the sensor behavior and thus requires frequent re-calibration or software compensation.
THE BENEFITS OF CAPACITIVE TACTILE SENSOR
The benefits of capacitive technology are that the two electrodes no physical interaction and operate in an elastic region, so the sensor is more sensitive and stable.
Another key benefit is that electrodes can be formed from any conductive material (conductive cloth, FPCB, metal fixtures) giving our sensors a wide range of design flexibility.
Capacitive tactile sensing has emerged as the preferred method for capturing contact-based pressure changes due to sensitivity, repeatability, stability and design flexibility.
A Comparison of tactile sensors
커패시티브 촉각 센서 | 저항 촉각 센서 | |
---|---|---|
구조 | 전도성 물질 사이에 압축성 유전체 | 멤브레인에 저항성 잉크 인쇄 |
정확도 | 탁월함 | 보통 |
반복성 (Repeatability) | 탁월함 | 열악함 |
공간 분해능 | Good | 탁월함 |
디자인 유연성 | 탁월함 | 보통 |
셈플링 속도 | 보통 | 탁월함 |
온도 안정성 | 탁월함 | 보통 |
what is Capacitance?
커패시턴스는 전하를 저장하는 물체의 능력을 측정 한 것으로 그림과 같이 영역 A가 에어 갭 D로 분리 된 두 전극의 고전적인 물리 등급 예를 통해 수없이 입증되었습니다. 공극이 감소함에 따라 커패시턴스 C가 증가합니다.
PPS는 이 원리를 이용하여 센서 패드와 센서 어레이를 만듭니다. PPS의 정밀한 제조 기술은 뛰어난 반복성과 감도를 가능하게하며, 고급 전도성 재료는 적합하고 신축성이 있어 산업 및 기타 하이브리드 센서 설계를 가능하게 합니다.PPS 센서 설계의 단순성은 고객에게 최적의 맞춤형 센서 솔루션을 제공합니다.
PPS 어레이(Array) 센서
To build our Tactile Array Sensors, we arrange electrodes as orthogonal, overlapping strips separated by a proprietary compressible dielectric matrix, which acts as a spring. A distinct capacitor is formed at each point where the electrode strips overlap.
Precision manufacturing techniques allow excellent repeatability and sensitivity, while advanced conductive materials allow for conformable, stretchable, industrial, and other hybrid sensor designs.
By selectively scanning a single row and column, the capacitance, or local pressure, at that location is measured. Our proprietary drive and conditioning electronics can scan through an array at high speed while optimizing settings to achieve the maximum sensor response from each force sensing element.