Need help to design mechanical mechanism

Hello everyone,

I want to create feeder cart with seperate section, that will be hangin on rails. 
Feeder cart will have four positions:

First one (First load) will be bottom gates closed, middle gates open to the top.
Second (Second load) will  be bottom gates closed, middle gates have to be locked in horizontal position.
Third  position (First unload) bottom gates open, middle gates have stay locked.
Fourth position (Second unload) bottom gates open and middle gates also open, that stuff drops out.

I want ask you advice how to design bottom and middle gates open, closing and locking mechanical mechanism (without any electronical parts). This feeder cart will be operating by one man. 
I have created middle gates mechanism, but maybe you have better solution. 


I really appreciate for any ideas.

Sorry for my english mistakes. English is not my native language.

Link to my feeder cart design:
 https://cad.onshape.com/documents/9bf2057d221de0e07143093b/w/42b5cff40a9a1fb3bed3cb14/e/cbc213062709ad380b4cb17b

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antoniraj1 month ago

Use solenoid valves in combination with pneumatic cylinders / piston arrangement. These type of arrangements are used in asphalt mixing plants all over the world

Shuchi0071 month ago

i like the link that you have shared here.

Nice design but unless the material requires it to be so complicate I would go for simple push flaps.
If manually operated it would not make much difference but the design is far easier.
Just a thought though...