Abstract: A timber-working device comprises a frame having a feed axis and a drive system configured to feed at least one stem along the feed axis. The drive system comprises a first drive arm pivotally attached to the frame on a first side of the feed axis, having a first rotary drive having a first wheel. A second drive arm is also pivotally attached to the frame on a second side of the feed axis, having a second rotary drive having a second wheel. The drive system also comprises a third rotary drive having a third wheel, and a fourth rotary drive having a fourth wheel, mounted on the frame on the first and second sides of the feed axis respectively. At least one processor controls operation of the rotary drives, such that in a first mode the speed of the respective wheels of the rotary drives on the same side of the feed axis is substantially the same, and in a second mode the speed of the respective wheels of at least two rotary drives on opposing sides is substantially the same.

Abstract: A timber-working device comprises a frame having a feed axis and a drive system configured to feed at least one stem along the feed axis. The drive system comprises a first drive arm pivotally attached to the frame on a first side of the feed axis, having a first rotary drive having a first wheel. A second drive arm is also pivotally attached to the frame on a second side of the feed axis, having a second rotary drive having a second wheel. The drive system also comprises a third rotary drive having a third wheel, and a fourth rotary drive having a fourth wheel, mounted on the frame on the first and second sides of the feed axis respectively. At least one processor controls operation of the rotary drives, such that in a first mode the speed of the respective wheels of the rotary drives on the same side of the feed axis is substantially the same, and in a second mode the speed of the respective wheels of at least two rotary drives on opposing sides is substantially the same.

Abstract: A method and apparatus for determining a characteristic, such as the stiffness, of a portion of a wood specimen characterised by the steps of a) producing an acoustic signal in the wood specimen part way along the length of the wood specimen, and b) sensing a response in the wood specimen part way along the length of the wood specimen including a reverberation from a first end of the wood specimen, and c) calculating a characteristic of a portion of the wood specimen from analysis of the sensed response. A related method and apparatus may be used to determine a characteristic of a portion of a tree stem during harvesting of a tree and the characteristic used to optimise the value of a log cut from the stem.