Project
AIM:
* TO study the system level simulation of all terriain vehicle.
KEYWORDS:
* CVT, look up table , dashboard and baja ATV.
SOFTWARE:
* matlab , simulink.
OBJECTIVE:
1.study the baja ATV model without dashboard.
2.study the baja ATV model with dashboard.
3.study the baja ATV model using look up table without dash board.
4. study the baja model using up table with dashboard.
INTRODUCTION:
transmission ,which transmitts the power from engine to the wheel through the shafts. it consists of 4 types mainly,
* manual transmission:
*countinuos variable transmission.
*semi-automatic trensmission .
*automatic transmission.
A countinuosly variable transmission , or CVT,is type of automatic transmission that provides more usable power , better fuel economy and a smother driving experience then a traditional automatic transmission ,the CVT is a system that make it possible to varry stepless the transmission ratio without interuption of the torque flow . therefore an infinite number of ratio (between a minimum and maxmum) are possible . it is an automatic ,signal speed ,and gearless transmission that can shift through an infinite number of gear ratio .this ability to scamless shift throgh these different gear provide a number of benefit including extremely smooth shift and exception fuel economy, A cvt drags top engine power from a small engine ,which gives drives acceleration then standard automatic ,transmission . because of their greater ability to control the engine speed range, CVTs produce fewer emission . cvt are also lighter then traditional automatic transmission.
STUDY-1:
by using simulink model of cvt consists of signal builder, generic, motion sensors , vehicle transmission , vehicle body ,type and solver configaration block ect.... as show in fig-1, the cvt subsystem includes transmisson block ,input and output shift inertia and motion sensore as show fig-2, the vehicle body subsystem includes vehicle body block , doble drumbrake and types as show in mass of the vehicle as 250kg and 2 axles which connects 4 wheel accordingly.
the signal builder is used as for input for brake , throttel and gear rattio. braker input is maintained as 0 for overall simulation .1 for overall simulation . the throttel input given by 0.3 for 20 secs and increases . the throttel value is mainly to control the flow or amount of fuel into the engine , if the throttel value increases flow. linearly deacrease s to 1.8 and maintained constant for overall simulation as show in fig (4-5).
STUDY-2:
the above figure show baja ATV, with dashboard ' model which consists throttel meter and braker input in the dashboard instead of given input through signal builder .rest of the block and subsystem are common in the above baja ATV model without dashboard as show in fig -2&3 . the main dashboard is study the result by varying the input of breaker and throttel ,which show that the velocity and speed of the engineer .the gear ratio is maintaintined as 2.3 seconds for 5 seconds and linearity deacreases to 1.8 and maintined constant for overall increasing the throttel ,the velocity and speed of the enginer & shaft increases.
STUDY-3:
by using simulink model of CVT consists of sleep time , generic, engine ,motion sensor ,vehicle transmission ,vehicle body ,types & solver configuration block ect..... as show in fig -7 .the cvt subsystem includes lookup table transmission block ,input and output shaft intertia and motion sensor are show fig-8, the velocity body subsystem includes vehicle body block, dobule drum braker and tyres as show in fig -9 the intial engine speed is given by 2100 rpm , mechanical rotational for drive pully and as 0.8 &0.7 respectly .the mass of the vehicle as 250kg and 2 axles which connect 4 wheel accordingly.
A lookup table is an arry of data that maps input values to output values ,there by approximating a mathematical function .give a set of input values. a lookup operation retrieves the corresponding output from value the table .if the lookup table does not explicity define the input values . simulink can estimates an output values using interpolation ,extrapolation or rounding where,
* An interpolation is a process for estimating values that lla between known data point.
*A rounding is a process for approximating a value by altering its digital according to a known rule.
the breaker input and throuttle input is given by step time ,which depends on the run time and varies according . by using lookup table for gear ratio which takes as input to output cvt and work according to the input gear ratio and obtained the output .this method is very effect which can avoid the unsual torque at the cretain speed and very easy to achieve greator velocity & endine speed . it work as closed look when the input is given by lookup table .the gear ratio of velocity .the maximum velocity reached as 57 kmph approximately.
figuer-10
STUDY-4:
FIG-11
The above fig- shows ,baja ATV with dashboard model using lookup table which consists throttel meter and braker input in the dashboard and indicated as consistant block.
In the brake is maintained as constant and increase in throttel which show increase show increase in velocity .the flow or fuel is increases when the throttel increases when from 0.3 to 1 thus ,the power inthe engine increases .the torque reaches approximately 7N-M at 1.8 gera ratio ,which deffines that gear ratio is directly proprtional to the torque this gear ratio. the speed & velocity can achieve maximum.
in the above fig. the primary shaft reaches high speed and secondarys shaft as low rotational speed because the radius of the primary shaft as more then the secondary shaft .the directly prortional to the radius of the shaft . as the radius increases the speed the shaft also increases.
in the above fig .the velocity is maintained as constant for throttel values as 0.3 and varying by increases the value of throtel .which increases the velocity of vehicle . by increasing the braker input the velocity of the vehicle deacreases according which show fig -14
in this above fig- tthe primary shaft speed increases by increasing throttel and deacreasing by increase brake input values .which defines that the throttel can more amount of fuel . which incrases the power of the engine and similar to the secondary shaft. the radius of the primary shaft as more then secondary shaft. the speed is directly prortional to the radius the shaft as the radius increases the speed of the shaft also increases.
in this above fig- the braker is maintained as constant and increases in throttle which show increases in velocity ,the flow of fuel increases in throttle when the throttle. increases from 0.3 to 1 thus the power in the engine n-m at increases the torque reaches approximate 7n-m at 1.8 ratio ,which define that gear ratio is directly proportional to the torque .
in tthis above fig - the velocity of the vehicle is maintained as constant throttle value as 0.3 and varying by increases the values of tthrottle which increases the velocity of vehicle . by increases the brake input the velocity of the vehicle decreases according which in fig- using lookup table , it works as closed loop by recording value within in the range by using extrapolation and interpolation by lookup table.
in the above fig the primary shaft speed increases by increases throttle and decreasing by increases brake inputt value , which defines that the throttel can flow more amount of fuel which increases the power of the engine and similar tto the secondary shaft .the radius of the primary shaft as more than secondary shaft tthe speed is directly proportional to radius of the shaft . as the radius increases the speed of the shafy also increases . the throttle values and brake input values can be varying in dashboard so, we can any particular value for input.
Conclusion:
1.As the throttle increase the velocity also increases which in turn the power in the engine also increases.
in the above fig- at the beginning the speed reducing becauses of gear ratio and ouput when the gear ratio increases the torque increases.
2.as the brake input increases ,the velocity decreases and engine also decreases at a certain brake input values the energy may shunt down and there is no power output. the engine power is inversity proportional to the brake input.
3.As the gear ratio increass, torque increases which in turn the velocity decreases.
in the above fig- the torque is increases by increases in engine speed ,at a particular point the torque is decreases when the gear ratio increases in order to achieve maximum velocity.
fig-23
in this above fig-the velocity is varying witth respect to gear ratio .for the high gear ratio the torque is move which decreases the velocity . by changing to high gear, the gear ratio partially also lets which can get high velocity.
4.which the help of lookup table , we can varry input value and also get the output value by using interpolation and extrapolation method .with the simulink can solve.