I recently installed and started teaching myself the Creo suite of tools. I needed a replacement for AutoDesk Inventor. I’ve posted the finished product of the tutorials for building a piston/ piston shaft. I would like to reach the same capability I previously held with Inventor. For those of you not familiar with Creo, Wikipedia offers this:
Engineers/pilots will notice, on my model, the abscence of wingtips and the exact airfoil is reproduced as best as possible for being lofted from drawings. This drawing was intended as low fidelity to facilitate a proposal. It meets those requirements.
Completing the Creo tutorial required some breakdown between both the text and the videos provided. Completed exercises are shown below.
A piston created in Creo (Creo Beginner Exercise 1)
A crankshaft to emphasis patterns and simplifying (Creo Beginner Exercise 2)
Two way ranging and Doppler systems are summarized. Differenced measurements or “differencing,” is explained. For additional explanation on differencing see Penn State’s course for Geospatial and GNSS professionals (https://www.e-education.psu.edu/geog862/node/1727).
There was some difficulty with projecting the slides to the screen so they have been added after the lecture was recorded.
The environment and relativity effects on radio and optical communications are introduced. One-way range measurement systems are introduced. GPS is provided as an example but it still applies to GLONASS and Galileo. Two-way range, Doppler, and differenced measurements are considered next.
Demonstrate understanding of orbital mechanics necessary to complete orbit determination course. In problem 1, position and velocity are converted between osculating elements and sub-satellite points. In problem 2, the receiver measurements confirm the node location varies over time. In problem 3 the equations of motion are numerically integrated for a GLONASS satellite for one day.
Continuing from ideal range and range rate measurements we examine how this applies in the larger context of orbit determination. We use examples to demonstrate real-world application. My apologies again for the difficulties I had bringing this recording to you.
I pick up again by reviewing the solution to the problem assigned during Lecture 1. (The link will take you to a solution using C++ on GitHub). A few common coordinate systems and reference frames are introduced, orbital perturbations are introduced, and an example problem to be solved in Lecture 4 is given to the class to start on.
We review orbital mechanics and Newton’s law of gravitation to prepare for orbit determination. We will cover the two body problem, orbital elements, and perturbing accelerations. We won’t finish the entire lecture today. We will continue on Monday.