Method of controlling operation of a vibratory roller

A vibratory roller, comprising:

• a roller drum;
• a vibratory mechanism disposed inside the roller drum, the vibratory mechanism comprising a rotatable shaft, a first weight fixed to the shaft, and a second weight connected to the shaft, wherein, in a first position, the second weight aligns with the first weight to create a high amplitude setting of the vibratory mechanism, and in a second position, the second weight partially balances the first weight to create a low amplitude setting of the vibratory mechanism;
• and
• a control unit for controlling the vibratory mechanism, the control unit operably coupled to an accelerometer for determining vertical acceleration of the roller drum, wherein the control unit is configured to turn off the vibratory mechanism upon determination of a bouncing indication value indicative of a vertical acceleration of the roller drum that exceeds a predetermined bouncing value,
• wherein the control unit is operably coupled to an eccentric position sensor for determining a position of the shaft
• wherein the control unit is unit is configured to determine a phase angle, wherein the phase angle is a difference in angular position between an eccentric force generated by the vibratory mechanism and a displacement of a roller drum of the vibratory roller, and
• wherein the control unit is configured to determine whether the phase angle is within a predefined phase angle range, and if phase angle is outside of the predefined phase angle range, to adjust the vibration frequency.

A method of controlling operation of a vibratory roller, comprising:

• operating the vibratory roller with a vibratory mechanism of the vibratory roller at a high amplitude setting;
• controlling a vibration frequency of the vibratory mechanism to maintain a predefined phase angle range, wherein a phase angle is a difference in angular position between an eccentric force generated by the vibratory mechanism and a displacement of the roller drum;
• adjusting the vibration frequency if the phase angle is outside of the predefined phase angle range;
• determining a bouncing indication value, wherein the bouncing indication value is based on a vertical acceleration of a roller drum of the vibratory roller;
• and
• upon detection of a bouncing indication value that exceeds a predetermined threshold, turning off the vibratory mechanism;
• and then
• operating the vibratory roller with the vibratory mechanism at a low amplitude setting or with the vibratory mechanism off.