156B Week 6

Overview of Status of Analysis, Design, Fabrication, Tests, etc.

• • The sensors were tested individually, but five did not respond well. Five new sensors will be fabricated to replace them. The sensors will be tested with circuitry that will be incorporated in the final DAQ system to lock in signal conditioning before finalizing the PCB design. After verifying the output of every sensor, the final layout will be arranged, encased in epoxy, and adhered to the final acrylic plate. Once the force hammer arrives, each sensor will be individually calibrated to extract the sensitivity constant for each sensor which will be utilized in the data analysis code to normalize the voltage readings.

  • Op-Amp circuitry delivered to Kaitlynn for intermediate testing before final PCB design is completed, need to see if the new sensors are any more sensitive than the ones currently being used for DAQ testing.

  • 16 to 1 Multiplexing circuit developed, some interesting finds, including switching time issues that might be due to high impedance sensors interfacing with the multiplexers switching too fast to ensure complete rise time of the multiplexer to the next sensor output.

Accomplishments from Previous Week

• • Tested individual sensor output (Kaitlynn)

  • Tested impact capability of adhesive epoxy for final layout (Kaitlynn)

  • Updated Multimedia on webpage to include testing throughout the design process (Kaitlynn)

  • Updated Team page to include team and sponsor pictures (Kaitlynn)

  • Selected bilayer potting compounds--Hard and Soft (Reuben)

  • Selected heat sink for microcontroller (Reuben)

  • Received Final golf faces (Reuben)

  • Delivered signal conditioning circuitry to Kaitlynn for testing (Chris)

  • Developed 16:1 multiplexing circuit, and developed code to switch between the multiplexers faster than 1 MHz (Chris)

  • PCB layout further developed, but on hold until new sensors are confirmed to respond favorably to Op-Amp signal conditioning (Chris)

  • PCB layout sent to Steve Roberts for look through and questions answered regarding bypass capacitance, ground plane layout (Chris)

  • Inertial Measurement Units researched for potential use as angle calculation (Chris/Reuben)

  • Developed trigger accelerometer code (Chris)

  • Started receiver enclosure CAD (Michelle)

  • Continued to optimize efficiency of MATLAB code (Michelle)

Goals for Next Week (list names after each item). Use specific and measurable objectives.

• • Fabricate five additional sensors to replace those not responding well (Kaitlynn)

  • Test sensors on circuitry used for DAQ to compare output in preparation for final PCB design (Kaitlynn)

  • Ensure new sensors respond appropriately to impact (Kaitlynn)

  • Arrange layout with working sensors (Kaitlynn)

  • Encase layout in epoxy (Kaitlynn)

  • Send final Driver head for manufacturing (Reuben)

  • Finalize adhesion process to golf face (Kaitlynn/Reuben)

  • Finalize potting mold CAD to insert driver head (Reuben)

  • Continue CAD of receiver enclosure (Michelle)

  • Finish optimizing MATLAB code that grabs data from Arduino serial monitor (Michelle)

  • Run long wires to accelerometer fixed to golf club head and swing to test if accelerometer can trigger an event (LED blink) (Chris)

  • Test if high impedance sensors can be converted to low impedance by placing conditioning Op-Amps between sensors and multiplexers instead of simply running sensors directly to multiplexers (Chris)

  • Test to mitigate crosstalk between sensor channels when switching multiplexers quickly (Chris)  

  • Finalize PCB layout corresponding to test data from Kaitlynn, and op-amp and crosstalk testing (Chris)

  • Shift to "tiered" layout, that uses wires to connect breakout boards instead of directly placing breakout boards flush with PCB to allow for better use of vertical space in the club.  Breakout boards and PCB will be suspended in potting compound (Chris) 

Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)

• • Recommends calibrating the sensors with the layout encased. Just make sure the sensors work before encasing them. (4/29 via Zoom)

  • Theoretically, the readings should not be different depending what side of the sensor is impacted. The discrepancy could be from how it was taped down, how flat it was positioned, or how taught it was pulled. (4/29 via Zoom)

  • Is 10 bit sufficient resolution? Recommends trying to step up to 12 bit. (4/29 via Zoom)

  • Work on sensor calibration with the DAQ system once it's completed. (4/29 via Zoom)

  • Recalls TaylorMade mentioning they see strains up to 1%. We emailed Brandon to see if there was any documentation to support this, but that data came from their FEA simulation, and no tests were physically done. (4/29 via Zoom and email)

Instructor Comments from Last Meeting and Actions Taken to Address these Comments  (indicate date of comments and if via email or in person)

• • N/A

Comments from Other Students in the Class (indicate date of comments and if via email or in person)

• • N/A

Risks and Areas of Concern

• • N/A

Resources or Information Required but not Available

• • Need impulse hammer for sensor calibration 

Schedule

• • Design final PCB and send out for manufacturing

  • Integrate sensor layout with DAQ system

  • Start force testing upon impulse hammer arrival (ETA 4 May)

Budget (list amount spent and amount remaining)

• • Amount Spent: $1,609.69

  • Amount Remaining: $1290.31

Progress on Report and Webpage

• • Report first draft completed

  • Webpage first draft completed

  • Continue to fill in Design of Key Components

  • Update report and webpage with additional testing and results found this week