How to use Relays and Vacuum pumps with Arduino ?

Hello everyone, This is my first time posting so please forgive me for some amateur mistakes.

I am a mechanical Engineering student and recently started working with Arduino and have no knowledge in electronics.

So, I am working on a project ie., Automatic window cleaner (link to the video) and I have made the basic body and have successfully ran two Gear DC motors via Bluetooth to control the up-down and sideways motion of my robot.
But now for suction I am very much confused and would really appreciate if you could help me.

I am using Arduino Uno and Adafruit Motor Shield [v1.2] and Bluetooth module HC-05 to run my motors.

For the Pumps I am using 12V Vacuum pumps

There are some doubts that I want to clear so please If you can help with the questions below:-

  1. Can I treat the Vacuum pumps as DC motors to use them with my motor shield and control them via Bluetooth ?

  2. I am using Solenoid valves and to switch the Solenoid Valves On/OFF I am using Relays, How can I control the relay to control the Solenoid Valves.

  3. These Solenoid Valves produce some 'Back EMF' and to protect the circuits from 'Back EMF' I am using a diode. Will a diode work or should I use a MOV (Metal Oxide Varistor) instead.

  4. And how can I activate the Relays (to control the Solenoid Valves) with the same Bluetooth app that controls my DC motors.

If you could help me in any why that would be appreciated.

Thank You very much

#!1) yes, a motor is a motor, your vacuum motors are just motors in the electrical sense.

#2) a solenoid is a coil. a relay is a coil. you need power to turn on the relay. this seems to be redundant.
you could use a FET or transistor, if you use a FET, make sure it is a logic level device. this means that you can use the Arduino 5volt and control a 24 volt coil. if you do not get a logic level FET, then you need to use the same voltage on the gate as you get on the drain.

here is the general use

#3) see links above. the diode is what is typically used

as for #4, not sure if I understand. a motor is a coil, a solenoid is a coil, a relay is a coil. all are driven with a FET or transistor, the signal is 5 volts. what that 5 volts connects to has nothing to do with how the 5v signal is generated.

runaway vaccuum.

if one foot does not grasp, you might have an open port and no vacuum. on a CNC table that holds down parts, we typically use a ball and a spring.

the spring is very light, the ball is pulled in by the FLOW of air. if the FLOW is great, the ball is pulled back and seals the hole. then there is only vacuum, no flow.

if the opening is covered, there is no flow, the spring holds the ball away from the port and the vacuum is directly on the plate being held down.

another style has a ball that sits high and only when the material pushes on the ball, does the port open and allow vacuum to reach the part.

the concept is that an open port and allow for the loss of suction.

http://www.m-powertools.com/products/vacuum/ball-valves.htm
http://anver.com/vacuum-components/vacuum-cups/cups-holddown/