Watertight Solenoid with Digital Timing Control

I am in search of an expert who can design and build a solenoid for me. The solenoid should be uniquely tailored to perform the following actions:

- Pop up and down swiftly in a sequence of three times.
- It should have the capability of a digital control for timed activations.
- must be able to run on a 12v wiring for long periods of time
- solanoid must be held firmly with plate.

This unit should be housed in a container that is fully watertight, considering it will be used outdoors with potential exposure to wet conditions. The overall size of the unit must remain within the following dimensions: no longer than 300mm and no wider than 50mm in diameter.

Ideal Skills and Experience:
- Background in Mechanical or Electrical Engineering
- Strong knowledge of digital timing controls
- Experience designing waterproof/watertight units
- Proven track record of designing and building solenoids

This project requires precision and an appreciation for detail. Therefore, I am interested in freelancers who have a strong background in creating similar units and ones who understand the complexity of the project specifications. Skillful execution and successful delivery within a reasonable timeframe will be highly appreciated.