I live in the south of England and we have had a few rare hot sunny days. I noticed how a big flower (sunflower?) always pointed at the sun which gave me an idea. I have a small solar powered fan that can clip to a baseball cap, I attached it with some gaffer tape and a small stick to the top of the flower stem and it has tracked the sun all day keeping the solar panel always facing the sun.
Anyone got any ideas as to how to scale this up to move a larger panel, perhaps have the flower controlling a servo connected to a bigger panel??

 

I would recommend a small DC powered gear motor of 1 or 2 rpm
Use a bicycle chain and gears to get a geared down movement for the panels.

 

Put sensitive switches on each side of the "sensor" so that one is activated when the sensor moves in that direction. The switch either activates a relay or H-bridge to run the motor in the correct direction.

 

Tie more sunflowers together?
Maybe even braid the stalks.. That look pretty neat..

 

I was thinking more of an optical sensor on the stork to use PWM to control a servo, or use a belt round the stalk just under the head of the flower, run the belt around the control knob on an aerial rotator, My Yeasu rotator has incredible torque so may give it a try.

 

Would it not be easier to forget the sunflower and use two LDR sensors separated by a cardboard wall mounted at the bottom of the solar panel which is all mounted on a motor driven base?

Basically, you would connect the two voltage levels of the LDRs to some differential amplifier that would detect which LDR has more light (this is the one that is directly facing the sun, or more towards the sun). This signal determines which way the motor should turn and when both LDRs are balanced (panel facing at sun directly), the difference is 0 and no more turning of the motor.

BTW, South of England here too and the sun has been great!

 

yes of course, but i liked the idea of a natural organic sensor

 

What happens when the sunflower dies?

 

A 555 plus two ldrs can track the sun in one dimension.

Two such contraps can do two dimension tracking of any light objects.

 

Using any sort of sun sensor not genetically inclined to follow the sun may lead your tracker to waste a lot of power tracking the brightest cloud in the sky.

Mariners have used the fact that the position of the sun at any given moment is completely determinate. So don't track the sun, calculate where it should be.

Of course, this depends on gaining enough energy via tracking to overcome the losses incurred by moving the damn array from side to side. Also making a secure but movable support that will not fail under high wind conditions.

But I do kinda like the idea of pointing a camera at the sunflower. Oh, are they cold tolerant for winter use?

 

What happens when the sunflower dies?

Cut the heads (flowers) to take the seeds and their bodies become Green manure.

 

 

Cut the heads (flowers) to take the seeds and their bodies become Green manure.

Ok.
But they sure don't track the sun well in that condition.

 

Ok.
But they sure don't track the sun well in that condition.

The sunflowers can be track the sun power, and even we eat their seeds, but the seeds no magic power, so we can't track the sun when we using the black cloth to cover our eyes and head.

Maybe someday in the future, the scientist can figure out how the sunflowers can track the sun power, and make the ee product to be a sensitive component, but the component doesn't like the cds or solar cells, that is the biological technology.

 

I think putting sensors is the best idea.

 

Hello,

Perhaps the following schematic might help:
http://www.electroschematics.com/8019/diy-solar-tracker-system/

It tries to keep he same amount of light on both sensors.

Bertus