Melexis undertook a major innovation project to improve robot interaction with fragile or different objects. A fully integrated haptic sensor launched by the company Tactaxis, the surface delivers 3D force vectors and is compact and flexible in structure. This enhances the robot's hands and pliers for delicate operations such as picking fruit. This technique has been successfully implemented in functional prototypes.
The sensor is equipped with a magnet embedded in an elastomeric material. Provides a soft touch interface that simulates the properties of human skin. This pioneering prototype utilizes its Triaxis technology to provide multiple 3D magnetometer pixels. This arrangement provides high sensitivity, and even small amounts of force can be detected to induce a response. The achieved force resolution of 2.7 mN is sufficient to distinguish a fraction of a gram (~0.3 g) of weight change. The prototype is very compact (dimensions are only 5mm x 5mm x 5mm), making it ideal for tight spaces.
The gradient method protects the sensor from magnetic field interference and prevents possible measurement errors. It can also cope with harsh conditions (temperature changes, etc.). Unlike other light-based tactile sensors, it is fully integrated. This will make it possible to manufacture factory-calibrated sensors in large quantities. This semiconductor process brings significant cost and reliability advantages.
"Robots require touch to manipulate fragile objects. For these types of applications, we have developed a new magnetic sensor that accurately measures contact forces while being robust to disturbances," explains Gael Close, global innovation manager at Melexis. "By developing the capabilities of our three-axis magnetic sensor technology, we have taken a significant step forward in robotic tactile sensors, providing a robust and competitive multi-axis sensing solution. We will now use the Tactaxis prototype as a further step The foundation of development work.”
White paper giving details Melexis 3D magnetic sensor prototype has been published by IEEE (Institute of Electrical and Electronics Engineers): T. Mr. N. Dupree and G. Turn off "Gradiometric magnetic Sensors Free from stray magnetic fields on manipulators and tentacles",IEEE Robotics and Automation Letters, January 2022.
