Technology

The commercially-available, market-leading tactile devices are all pressure mapping systems, i.e. they only measure forces that are perpendicular to the surface. Most of the available tactile sensor arrays are based on either capacitive or resistive principles. A typical market-leading tactile system has 100-3000 sensing elements, with a spatial resolution ranging from 0.64 mm up to 17 mm (0.025 in - 0.7 in), a sensing area from 3x3 mm² to 578x884 mm² (0.12x0.12 sq in - 22.7x34.8 sq in) and pressure range somewhere between 0 and 25,000 PSI (0-175 MPa).

The difference between normal and shear force

TactoLogic Technology - The heart of all TactoLogic devices is a Si-based MEMS (Micro-Electro-Mechanical System) tactile sensor, using the piezoresistive principle. Our patented technology combines porous-silicon etching with standard CMOS processes, resulting in smart three-axial force-sensors. Each tactile element (taxel) of the sensory array is an under-etched, deformable, cross-shaped silicon bridge, with built-in strain gauges. The bulk silicon as the structural material provides highly linear characteristics and robust functioning, while the geometrical design enables precise and independent measurements of all three components of the attacking force. The small taxel size and the dense array structure results in a spatial resolution comparable to human touch. As a biomorphic feature, the sensors are protected - and their characteristics are enhanced - with unique, skin-like elastic covers.

TactoPad 8x8

Array Properties - Our tactile devices are carefully designed to approximate the human fingertip in size, sensor density and sensitivity. Our arrays currently contain 2 (2x1), 4 (2x2) or 64 (8x8) 3D-force-sensing elements, with a sensor-to-sensor distance of either 0.8 or 1.5 mm. The sensitivity of the devices is comparable to a light touch, with a load range of 0-1 N in each direction.

System Level Features - All our systems are connected to standard PCs through special data-acquisition electronics. The whole system is USB powered for Windows PCs and is supported by TactoSoft, a professional data-acquisition and analysis software, displaying the 3D force field through 2D component maps, 3D vector field graphics or time-series, with additional data analysis features.