This year’s mission is to design a container and two auto-rotating maple seed science payloads. The CanSat will be launched to 700m using a high-powered model rocket. The CanSat then descends using parachute at 15 m/s. At 500m, the first payload is released and the second payload will be released at 400m. These payloads will rotate and descend slower than 20 m/s. While descending, the container will collect its own telemetry as well as telemetry from both payloads.
Throughout this year, we have three main deliverables: the Preliminary Design Review, Critical Design Review, and CanSat hardware to launch at the competition. Since this year’s competition was transitioned to virtual, we have additional environmental tests and demonstrations. We follow a yearly design cycle, adhering to deadlines and requirements imposed by the competition. This ensures all teammates gain experience with the full engineering design process.
Figure: Diagram of 2020 - 2021 CanSat Mission
As a competition project, our problem statement has two parts. Our technical goal is to design and build a CanSat, which consists of a container and science payloads. The CanSat descends from an altitude of 670 to 725 m; first the container and payload descend together under a parachute at a velocity of 15 m/s. The first payload is then released at 500 m from the container and begins rotating rapidly to descend at a rate less than 20 m/s. At 400 m, the second maple seed will be released.
The Payload must be equipped with sensors for air temperature, air pressure, and rotation rate. It must be capable of transmitting this data in real-time to the container. The container must relay all data as well as have a GPS sensor, pressure sensor, battery voltage measurement, and audio beacon. The scope of our project is designing and building the CanSat and ground station. The launch system (a high-power model rocket) is provided by the competition organizers to standardize launches. The CanSat container must protect the science payload from damage during the launch and deployment.
Our overarching goal is to perform well in the CanSat Competition. Additionally, we need to ensure all CanSat teammates gain practical experience in the engineering design process. Finally, we must ensure our project satisfies the MAE Department’s requirements for senior design and represents UCI well at design reviews and the CanSat Competition.
While there are 66 requirements published by the CanSat Competition. The most important requirements regarding CanSat's design are listed below:
CanSat is a relatively small team that works on a tight schedule, so all members must do their part. Everyone is responsible for a critical component of the final project, and we believe everyone should have a say in how the team is run. Decisions should be made transparently, especially when they affect the whole team. Logistical information such as budgets and schedules should be easily accessible to all.
Our project advisor is Professor Roger Rangel. In addition to attending our meetings and providing technical advice, we trust him to ensure our team remains on track, and to help us resolve any conflicts that may arise. For manufacturing-related problems we can consult Fabworks and RapidTech staff, fabrication facilities on campus. We can also seek advice from external sources; previously, we received advice on fabricating our CanSat’s carbon fiber structure while obtaining quotes to have the parts cut via water-jet.
The CanSat team leads include Brandon Wong, Andrew Zhao, and Alan Wong, as shown in the organizational chart above. Brandon Wong contributes to the mechanical team and works on administrative tasks for the team. Alan Wong manages the software and electrical team, consisting of Oscar Rene Jr. Castro, Briggs Judd, and Ian Cumming. Andrew Zhao manages the mechanical team consisting of Thomas Slagle, Tyler Wong, and Joshua Brusa.
Team Leads ensure that all team members are meeting deadlines, provide guidance and advice for team members by creating and delegating tasks for each team member. Every student is involved with researching components of the CanSat. Mechanical members focus on the mechanical structure and aerodynamics while the electrical/ software members focus on the probe controls and telemetry, as well as developing the data plotting and logging features of the ground station.
Our goal is to design and build the best CanSat possible, meeting all competition requirements. In addition, we aim to provide all team members with invaluable experience in the engineering design process.
The team achieved our fall goals where we completed researching and design work and began to procure resources and begin our first prototypes. We have also submitted our Preliminary Design Report.
During winter we will focus on manufacturing and improving our designs for prototype two, and completing the CDR. In spring we will be completing testing, correcting any issues, and preparing for the competition directly after spring finals week. Our competition milestones are the Preliminary Design Review presentation on February 1st, the Critical Design Review presentation on April 2nd, and the competition from June 11th — 13th, 2021.
The mechanical team completed designs and calculations for the container and payload. We calculated the descent velocities of the parachute and wrote python sizing scripts to estimate the size of the maple seed payloads to achieve the desired velocity that the competition required. In addition, we completed the SolidWorks 3D Models, drafted drawings, and ran FEA structural simulations on the container to withstand 15G launch acceleration and 30G shock.
Figure: Container FEA Analysis
As for the software and electrical team, all electronics components (sensors, capacitors, resistors, ect.) have been selected and the container and payload PCB designs are completed. Firmware to read the sensor data and ground station is being completed. One of the prototype payload PCB boards have been completed and is currently being tested.
Figure: Payload PCB Rendering