Best solution for pushing arm

my project is intelligent conveyor belt system which can Identify the color of an object and take action based on it, but I have a problem , which is the pushing arm , I cant find suitable one compatible with Arduino Mega 2560 .

I have ran across so many types like the solenoid and the DC motor ones , but they're either expensive or really slow

I want a reliable pushing arm any suggestions ?

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Powerful, fast and reliable = expensive You decide which property is least important.

For weak, fast and reliable, recycle the voice coil actuator from a dead mechanical hard disk.

mikb55: Powerful, fast and reliable = expensive You decide which property is least important.

For weak, fast and reliable, recycle the voice coil actuator from a dead mechanical hard disk.

That's actually a pretty good idea , I'll look into it .Thanks