You can throw a Raspberry Pi camera and OpenCV at the problem and approach it through software, or you can buy an off-the-shelf RGB sensor and wire it up to an Arduino.

The Air Force Research LaboratoryResponsible for the flexible Arduino board has been led in conjunction with NextFlex, America’s Flexible Hybrid Electronics Institute. The team has now unveiled ...

The Pressure Sensor Module incorporates a material called Velostat with the Arduino. This material adds more resistance when more pressure is applied to the material. This module also uses the RGB LED ...