FIELD OF INVENTION
The present invention relates to a system for measurement of tractor wheel slip. The measurement is done through Global Positioning System (GPS) to optimize the tractor performance.
BACKGROUND/PRIOR ART OF THE INVENTION
Tractors are used in different farming operations, the conversion of engine power to tractor drawbar power (Overall efficiency) is required to be optimized for better tractor productivity & increased fuel efficiency. Tractive efficiency is one of the main component of overall efficiency (Engine efficiency X Transmission efficiency X Tractive efficiency), which is defined as ratio of Input power to the rear axle to the drawbar power of the tractor in percentage. The maximum tractive efficiency occurs when the drive wheel slip lies between 8 to 15 percent, which falls rapidly from the maximum value in case the slip is not in above mentioned range. Generally, during field operation, operators do not know wheel slip value and therefore cannot control the wheel slip. This leads to loss of power & higher fuel consumption. Knowing the importance of slip, some researchers have used Doppler radar and photo transducer to measure the slip. But these methods are costly and not reliable for measurement at various field conditions.
A system is therefore needed to measure and indicate/display slip value for selecting the correct combination of gear & speeds for a particular field operation, there by getting maximum drawbar output from the tractor to optimize the tractor performance (In terms of improving power output and fuel consumption) for various farming operations.
For haulage operation, actual tractor speed is a very important parameter to improve the transport productivity. So, this can also be used to measure the actual road speed.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a system for measurement of tractor wheel slip which is reliable.
Another object of the invention is to provide a system for measurement of tractor wheel slip which is accurate.
Still another object of the invention is to provide a system for measurement of tractor wheel slip which is cost effective.
Another object of the invention is to provide a system for measurement of tractor wheel slip which overcomes disadvantages associated with the prior art.
Yet another object of the invention is to provide a system for measurement of tractor wheel slip which is simple in construction.
STATEMENT OF INVENTION
According to this invention, there is provided a system for measurement of tractor wheel slip comprising of a means to measure pulses is connected to a controller to obtain slip, which is in communication with global positioning system.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawing and wherein:
Figure 1 shows: system of the present invention for measurement of tractor wheel slip.
DETAILED DESCRIPTION OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWING;
The present invention discloses a system for measurement of tractor wheel slip (as shown in fig. 1). The tractor wheel slip at different farming conditions are measured with the help of two magnetic pickups, GPS (Global Positioning System), a Controller (Mother Board) and one display unit mounted on the tractor. Magnetic pickups are positioned on the rear axle (LH &RH side) to measure the number of pulses per revolution to get theoretical tractor speed. Similarly, Global Positioning System is located on back side of seat back to measure actual tractor's forward speed.
Reference may be made to Fig. 1. The output from magnetic pick up and GPS is provided to controller. The controller is installed with an algorithm to generate the theoretical speed by multiplying mean revolution per minute of rear wheel (Arithmetic mean of both LH & RH axle RPM) with rolling circumpherence (Distance traveled by rear wheels in one revolution on hard surface) .Also, another algorithm is installed to calculate the wheel slip by calculating the
actual and theoretical speeds of the tractor as defined in below equations. The percentage wheel slip is displayed on dashboard of the tractor and a provision of a red indicator to show over & under slip when slip goes out of range i.e. 8 to 15 percent. A separate display is also provided on dashboard for display of actual road speed of the tractor as measured through GPS.
Wheel Slip or travel reduction is a reduction in distance traveled and/or speed that occurs because of Flexing of tractive device (Tyre)
Relative movement between the surfaces (Tyre & Ground) • shear within the soil (Soil & tyre Interaction).
(Equation Removed)
where, Va = actual velocity, m/s
Vt= theoretical velocity, m/s
S = wheel slip, %
Nn = rpm of right rear wheel
Nr2 = rpm of left rear wheel
dr = distance covered in one revolution on hard surface by rear
wheel, m
ADVANTAGEOUS FEATURES OF THE PRESENT INVENTION
1) Improved fuel consumption (lit/ha).
2) Reliable with high accuracy of measurement.
3) Improved tractive performance
4) Improved transport productivity
5) Data can be generated 8B stored for future (Through internet).
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:-

WE CLAIM:
1. A system for measurement of tractor wheel slip comprising of a means to measure pulses is connected to a controller to obtain slip, which is in communication with global positioning system.
2. A system as claimed in claim 1, wherein the means comprising of magnetic pickups positioned on rear axle (LH and RH side) so as to measure number of pulses per revolution to obtain tractor speed.
3. A system as claimed in claim 1 or 2, wherein the global positioning system is located on back side of seat to measure actual tractor's forward speed.
4. A system as claimed in any of the preceding claims, wherein said controller is provided with output from the magnetic pickup and global positioning system to generate theoretical speed of tractor and wheel slip.
5. A system as claimed in any of the preceding claims, wherein the controller is connected to a display for display of actual road speed of the tractor and percentage wheel slip.
6. A system as claimed in any of the preceding claims, wherein the system is associated with several advantageous features such as herein described.
7. A system for measurement of tractor wheel slip substantially as herein described with reference to the accompanying drawing.