%0 Journal Article %A SHahmirzaee, N %A Kamgar, S %T Design, Fabrication and Evaluation of a Laser- Based Torque MeterFor Silage Corn Yield Monitoring %J Journal of Crop Production and Processing %V 13 %N 47 %U http://jcpp.iut.ac.ir/article-1-1087-en.html %R %D 2009 %K Torque meter, Laser sensor, Mass flow rate, Chopper, Silage corn., %X One of the most important goals of precision farming is preparing yield map. Recently in Iran, planting of corn has received special attention. Therefore, among the different methods of yield measurement such as using impact sensor at the outlet port of forage harvester (chopper), displacement sensors at feed rollers of forage harvester, continuous measurement of discharged material to trailing wagon and using the torque meter, the present study made use of the torque meter method. This method consisted of a torque transmitting shaft equipped with laser-based encoders to monitor twist in a real time mode. The unit output could be exported to a computer via a microcontroller installed into the interface device. For calibration of the torque meter output with material feed rate in lab conditions, a conveyor was used to feed homogenous amount of material at a specific rate to the chopper. The experiment was conducted at 3 feed rates of silage corn and at 3 feed roll speeds of the chopper with 3 replications. Correlation between the feed rate and recorded power at different gears of the chopper was established. Relationships between feed rate and recorded power of the chopper at gears 1, 2 and 3 were linear with calculated R2 of 0.95, 0,98 and 0.98, respectively. %> http://jcpp.iut.ac.ir/article-1-1087-en.pdf %P 693-704 %& 693 %! %9 Research %L A-10-463-1 %+ %G eng %@ 2251-8517 %[ 2009