| CPC B66C 23/72 (2013.01) [B66C 23/701 (2013.01); B66F 11/048 (2013.01)] | 22 Claims |

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1. A telescoping crane arm, comprising:
a telescoping crane arm having an outer section and one or more telescoping inner sections;
a counterweight carrier movable on the outer section, the counterweight carrier linked to at least one of the telescoping inner sections;
an actuator for simultaneously moving at least one of the counterweight carrier and at least one of the telescoping inner sections in opposite directions;
a payload at a first end of the crane arm;
at least one sensor for sensing a position of the payload;
an electric motor configured to apply torque to the outer section; and
a computer controller electrically connected to the at least one sensor and to the electric motor, the computer controller controlling the electric motor to compensate for an imbalance due to movement of the payload.
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