Draft power requirements of modern implements
The following test reports show the draft power requirement of modern implements. At this, beside the draft force, also the working speed is analysed. The draft force is measured at the point of intersection between the horse(s) and the implement, the working speed at the implement itself.
During the field tests the measured data are memorized in data loggers and then analysed with various data processing software.
Actually the following programs are used:
- Akrobit Almemo View
- Microsoft Excel
- MathWorks Matlab
- OriginLab Origin
The acquisition technique will be completed in the future by other components, such as:
- Non-contact dynamic torque sensors for evaluating the mechanical efficiency of the implements.
- Heart rate monitor to determine the load of the horse
- On-board LED display of the measured draft forces for didactic purposes
Following our own measurings and scientific literature values (Breidbach Siegfried (D) 1957 / Brunner Walter (CH) 1942 / Spugnoli Paolo et al. (I) 2005 / Teichmann Wilhelm (D) 1928 / Van Rijn Frederik Jan Jacob (NL) 1929) a reference value of 0,88 kW (1,2 hp) is considered for the average continuous power of a medium sized draught horse (e.g. Ardennes) in longer work effort. This corresponds to a draft force of about 0,78 kN (draft resistance 80 kg) at a usual working speed of 1 to 1,25 m/s (3,6 to 4,5 km/h).
This draft power can be generated by a draught horse without excessive strain, also on several consecutive days, at field work. Temporary higher draft forces, up to 0,98 kN (draft resistance 100 kg) can be achieved, but only with enough breaks during the work. For animal welfare, implements with a draft force requirement greater than 1 kN respectively a draft power above 1,25 kW (1,7 hp) per horse under continuous duty are not considered in the following test reports.
For quick overview the power requirement of the implements and machinery is shown, beside the measured values, also in coloured pictograms in relation to the above mentioned reference value.
The colours of the pictograms are as follows:
For small horses (e.g. Fjord), which possess 20% less draft force as a medium sized draft horse under continuous duty, the power requirement has to be set a class higher.
Regard must be given to the fact that the measured values depend for tillage implements from the soil conditions and the working depth respectively for haying implements from the harvest size and composition. Not least, the measured data is also influenced by the horse’s pace and the topography.
Our present test fields in Italy and Luxembourg are flat, with light to medium heavy soil and mainly without stones. For other circumstances the power requirement of the implements has to be adjusted.
Test reports already published:
Test reports published shortly:
- SmP 2017-1 SmP Kombi-Roll 2.1
- SmP 2017-2 SmP Kombi-Setz 1.0