Motion Artifact-Resilient Zone for Implantable Sensors

The miniaturization and flexibility of wearable and implantable devices allow humans to carry them directly on or in their bodies, thus enabling these devices to measure biometric signals in real-time anywhere. However, as they are embedded or implanted into an actively moving human interface, motion artifact noise inevitably occurs. Typically, devices are laminated or implanted on body surfaces, but the positions of such devices cannot be designed without any discussion of the noise. Thus, this paper investigates an approach that minimizes the noise to achieve negligible motion artifacts in implantable micro-devices that have a specific angle on the surface of the body, while maintaining the function of sensor. The device with a specific angle successfully detects the target signal, while motion artifacts-such as tension, compression, and bending-disturb the measurement. The pulse signal on a wrist is well measured while the hand is rotating, and artificial skin implanted on a rat can distinguish external pressure from the movement noise. A thermometer sensor that follows the same rule is further examined. Therefore, this approach is expected to be useful in numerous areas including human interface-based medical devices, virtual reality, and health aids to improve quality of life.