From the last blog, the electronics were connected to the finalized components such as the car’s 12 volt battery, steering wheel’s limit switches, and solenoids. Further progress has been made to the code as well, such as changing the shift sequence so the drivers don’t have to reach over when shifting from neutral to first gear while holding the clutch lever located in the cockpit’s left side. An additional improvement that was made, although not required, is giving the drivers the ability to shift into neutral from any gear. This will prevent the need to press the paddles multiple times as opposed to a single press of a dedicated button for this quick-action. Current electrical tasks involve replacing the Arduino jumper wires with the finalized solid-core wires.

                                                      Figure 1: Electronic components assembled

The pneumatic components have been nearly finalized. The air tank used is 80 cubic inches rated for 4500 PSI, the regulator used is custom adjustable output pressure from 0 - 250 PSI from Palmer’s Pursuit Shop, an on/off valve will be used for continuous airflow, the cylinder will be swapped for a larger bore size, and hoses were purchased. The current setup for the tank can be shown below: 

                           Figure 2: Air Tank with On/Off Valve, Custom Regulator, and Hose output

Due to budget, a cheaper alternative was used for the 4/2 solenoid by using 3 3/2 solenoids on a rack. This can be seen below:

                                                               Figure 3: Solenoids Purchased

With these solenoids, one solenoid will control stroke A, another stroke B, and the third solenoid will control the piston's return to neutral position. Since these solenoids are rated for around 120 PSI as maximum working pressure, the larger bore-size piston is needed to prevent maxing out the solenoid. The old cylinder will be returned for a full refund and the additional air tank regulator will be as well. The air tank shield dimensions have been updated to 5” x 10” but the wall thickness and FEA is still pending because it needs to withstand the air tank exploding.

In the work period of February 15 to March 22, the team plans on finalizing purchases for any miscellaneous fittings required, working on validation plans for the project, and finishing the remaining fabrication. The fittings needed are reducers from the solenoid rack to the hose. As for validation plans, the pneumatic system and electronics will be tested soon, however, a high-pressure pump is still needed. This pump has been provided by a Cougar Racing team member but it needs a new filter to prevent it from pumping water into the air tank. Once this filter is obtained, experimental validation can be started to measure the force output by the cylinder. The remaining fabrication will be mounting tabs required to add parts to the FSAE chassis, the steering wheel, electronics housings, and air tank shield.

Some present electrical obstacles concern making the electrical connector for the quick release. This involves male and female ports being separated when the steering wheel is disconnected, allowing the wire harness to remain in the car. The electrical connector will be made up of 3D prints and copper pogo pins.

Additional obstacles in terms of pneumatics will be the high-pressure pump filter depending on the budget required. To resolve this, immediate action is needed to prevent any further delays. The air tank shield needs to be further developed and revised through FEA. A validation plan will need to be established however, it's likely to increase to a wall thickness that will be harder to test with.

Overall, the team needs to finish fabrication as soon as possible and begin to implement a validation plan for all components to meet our milestones.