Overview of Status of Analysis, Design, Fabrication, Tests, etc.
The derivation of the equations of motion have been done but the controller has not been designed
The final unistrut structure has been designed including mounting brackets and the required bearings and brake
Accomplishments from Previous Week
Equations of motion for the pendulum system were derived
A simulation was run in Working Model to visualize the system during wave motion
More information about the brakes was obtained
The parts list was verified by our sponsor
A new Solidworks model of a A-frame unistrut structure was designed
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Finalize control algorithm on the simulation (Ky/Chris)
Demonstrate the system response in Matlab
Order the materials and appropriate hardware from McMaster (Ky)
Design the handles for physical testing of the system under oscillation (Derrick)
This will be for ease of operation and will not inhibit the initial build time
Find a set of barbell weights for use as the dummy weight where the antenna would be (Zhan)
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
4/25/2012 (Sponsor Meeting)
Our sponsor brought in one of his colleagues to discuss the list of parts and the structure itself
He could not foresee any issues with the design or the components but suggested we check the slipping torque of the locking collar
An idea came up for water jetting a rocker base for the setup but was determined to not be necessary
He additionally advised that we make the control system account for surging or purely translational motion
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
4/23/2012 (Professor Meeting)
Professor Tustaniwskyj advised the purchase of at least 2 brakes just in case one fails
We spoke with our sponsor and he agreed that it would be a good idea to order a backup
Suggested we look into increasing the voltage to make the system respond more quickly
The manufacturer informed us that increasing the voltage does increase the response time, but he was unsure on the limit and relationship of these variables
Asked us to look into expediting shipping directly to San Diego instead of routing through New Jersey
Rerouting through New Jersey would need to take place only if the brake size was not on the shelf and had to be bored out
Suggested locking a washer to the bearing for easy removal and replacement
Comments from Other Students in the Class (indicate date of comments and if via email or in person)
None
Risks and Areas of Concern
The control method has still not been determined
Currently, we are planning on implementing PID control with manually tuned gains
A control algorithm that could predict the pendulum motion would be more accurate but may not be necessary
To make disassembly easier, a design with locking washers instead of press fits needs to be completed
The force required to pivot the structure during testing is unknown
Resources or Information Required but not Available
In regards to the control of the system, we are not certain how to accomplish control of a nonlinear set of motion equations
Our approach wat to attempt a Laplace transformation in order to get the transfer function, but this does not seem possible
The contact from the brake manufacturing company could not tell us if the brake could be gradually applied or if the system was full on/off
Schedule
Describe upcoming milestone
Update Gantt chart.
Budget (list amount spent and amount remaining)
$0 Spent
$4000 Remaining
Progress on Report and Webpage
The rough draft of the final report has been updated and compiled into one document
This week, the report will be revised and finalized for the first submission