mechatronics/mechanical design: Electronically controlled liquid flow in measure of .03 oz(1ml)

You have to design a small container with three housings and its three separate taps connected to each separately. That means, non of these solvent should get mixed anytime. Container capacity will be about 150ml -200ml. And will carry liquid with density more of skimmed milk. You have to come with a design approach of a electronically controlled tap which will allow to pass liquid in measure of ml. Measurement will be in ml, that means, electronically it will be signaled to pass 1 ml or 2 ml or 3 ml up-to 20 ml. Also, as solvent settles at bottom of container after leaving it for some time, so container has to be shaken well before releasing liquid. Your challenge is how to achieve it with a cheaper solution yet maintaining accuracy. Cost of end product is a very critical on selecting design to go with. If you take part in this contest then it is important for me to contact you based on your design approach. So please don't forget to share along with when taking part. As a solution you need to provide me the complete design which I could post to my vendor for creating physical model. Embedded/electronics part is our responsibility, you have to come up with mechanical design along with any motor you are using, such as stepper motor or DC motor, etc (just for example, please don't get biased by it). More the ready solution available, better for us to go with. Thank you.