Just a peeve of mine, students conflating what they want to with what they have to do.
Teacher gives an assignment prompt. No specific demand to do a particular thing. Student thinks up a thing that may or not be possible. When a student asks for help in how to do an impossible thing, and says it's the assignment requirement, it's misleading and makes people unable to realize that just saying 'no, that's not possible' is an option because everyone things the demands come from the teacher, not from the student's imaginings. I.e., it's as if you told us that your teacher told you to build a transmitter and a receiver with one Arduino at your disposal.
Now, explain what the assignment is actually asking for, and then we can better suggest how you can fulfill the requirements with what equipment you have. Explain the equipment that you have. What kind of power source or sources do you have available? What are the details about your DC motor? You said this was a part of something bugger, so maybe describe what needs to happen.
There may very well be for you to accomplish some variation of your vision, you just have to be willing to help those who are trying to help you learn from the experience.