Abstract: A system is for sensing a property of a material mat from a construction vehicle. The system includes a sensor for sensing the material property and a positioning mechanism connected with the vehicle and with the sensor. The mechanism displaces the sensor between first and second positions with respect to the vehicle as the vehicle displaces with respect to the material mat. The first sensor position is spaced a substantial distance above the mat upper surface. The second sensor position is located proximal to or on the mat surface such that the sensor is able to sense the material property in the second position. A controller operates the mechanism to sequentially displace the sensor from the first to second positions, permit the sensor to remain disposed at the second position for a period of time, and displace the sensor from the second to first positions after the period of time.

Abstract: The present invention is directed to a control system for sensing the vibration amplitude on a vibration compacting machine. In addition, the control system modifies the rotational speed of the eccentric assembly based on the vibration amplitude of the eccentric assembly. In one embodiment, the control system modifies the rotational speed of the eccentric assembly to match the optimum speed for adjusted vibration amplitude when the eccentric assembly is adjusted to increase or decrease the vibration amplitude. Reducing the rotational speed of the eccentric assembly at high vibration amplitudes minimizes wear to each of the load bearing components in the vibration compacting machine resulting in an extended service life for the vibration compacting machine. Similarly, increasing the rotational speed of the eccentric assembly at low vibration amplitudes increases the effectiveness of the vibration compacting machine.