This chapter describes the design of a smart particle (SP) used to monitor the behavior of particles inside river beds, which is used to study the forces and pressures of water flows that cause the particles to be lifted up. In developing this application, low-cost inertial sensors have been utilized to make the SP capable of measuring its own accelerations in all three coordinates. The SP described in this chapter has the ability to accurately monitor the forces and accelerations of the particles in all three directions while using low cost and small size components. Studying particles transport usually requires that the particles are in a controlled laboratory environment called flume. The SP was tested inside a real flume in order to evaluate its final performance. Measurements performed by a video camera are used as a reference to verify the outputs of the SP.