You do not need to do any kind of Solidworks or Autocad rendering of the design. And yes, you will be using pictures of your model, but labeling it with the full-scale measurements of the design in meters (no uncertainties here, because design dimensions by nature do not have uncertainty).
You should also say somewhere in the report the size of the model, i.e. you created a scale model of the design that is 1/50th the size. It probably wouldn't hurt to also include the dimensions of the model.