electronic seed planter need help

[nitinkpalte_be]

i m in agricultural engineering college, i want to develop microcontroller based electronic seed planter which may used with tractor or power-triller. distance between seed plantation very from 15cm to 60cm. idea is to calculate distance travelled by vehicle compair it with user requried entered distance value.
pls help me how to calculate distance covered in centimeter speed of vehicle is around 1km/h
i m using AT98C52

 

[ericgibbs]

i m in agricultural engineering college, i want to develop microcontroller based electronic seed planter which may used with tractor or power-triller. distance between seed plantation very from 15cm to 60cm. idea is to calculate distance travelled by vehicle compair it with user requried entered distance value.
pls help me how to calculate distance covered in centimeter speed of vehicle is around 1km/h
i m using AT98C52

hi,
What about from the tractor driving wheels.?

If you had a changeable disk, with disks having holes at different positions on the disk periphery, you could have a totally mechanical solution.

BTW: the Romans used a similar method 2000 years ago for measuring distance.

 

[3v0]

Google for it
1 km/h = 27.7777778 centimeters / second

1 seed per second will space the seeds 28 cm apart
so the time you are looking for is
time_between_seeds = (1/28) * (distance_between_seeds_in_cm)

hi,
What about from the tractor driving wheels.?

If you had a changeable disk, with disks having holes at different positions on the disk periphery, you could have a totally mechanical solution.

BTW: the Romans used a similar method 2000 years ago for measuring distance.

Such a system existed 20 years ago. It was called an air seeder. It used a drum with holes and vacuum to pickup the seeds. The result was very even spacing.

I imagine the OP could use a similar drum to pickup the seeds and vary the drum speed electronically to achieve variable spacing. But I would think that in 20 more years they already figured this out.

I would monitor ground speed by counting the seeder/planter wheel rotations. If measure ground speed in cm/s the calculations should be easy.

 

[nitinkpalte_be]

thanks for reply
pls give suggesions on my idea for measuring distance
i used LED as light suorce, LDR as sensor and LM324 as comaprator to generate square wave as o/p as light passes through hole. this pluses are feed to microcontroller and measured as count of distance in centimeters.
idea is to design a wheel with hole around its circumference. spacing between hole is 1cm. and mechnically arrange this measuring wheel with another ground wheel of same diameter.
i m thinking in this way because speed of vehicle may vary time to time, so is it possible to impliment this idea rather calculating speed of vehicle and then calculating time_between_seeds?
will it work? if not pls suggest me another method with detail as i m not too good in electronics, studing electronics & microcontroller.
thanks in advance.