This paper proposes a force-sensing wing, Senswing, to enhance the intelligence of flapping-wing aerial vehicles (FWAVs). Force perception is a crucial capability for robots to interact safely and effectively in unknown environments. However, FWAVs perform flapping motions with significant acceleration and deceleration, which can cause the flexure element inside force sensors to deteriorate due to repeated loading or even fail due to impulsive forces. To address this, we constructed a force measurement system by attaching 16 strain gauges directly to the wing root while maintaining high rigidity. We confirmed that the external force measurement capability closely matched the values obtained by a six-axis force sensor, with almost no error. Additionally, when measuring aerodynamic forces during wing flapping, the sensor could detect differences in wind speed even during flapping. With this sensor, FWAVs can achieve in-flight measurement of thrust and lift through a force-sensing system.

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