Week 2

(1/16/12-1/20/12) 

1. Overview of Status of Analysis, Design, Fabrication, Test, etc

   1. • Conducted kinematics analysis

        • In X and Y axis,

          • Determined inertia of the system

          • Determined necessary torque for the system

          • Determined necessary power for the system

      • Investigated servo brushless DC motors, brushed motors with separate encoders, and direct drive servo motors

        • For the servo motors, we are required to purchase a paired driver system. However, with our load to rotor inertia, regular driver with PID will not be stable. So, we had to look into the programmable driver system but they were prohibitively expensive.

        • For brushed motors with separate encoders, we had to find a motor driver with an Analog Digital Converter that had high enough resolution that could meet our requirements.

        • Even though direct drive motor meets most of our requirements, we still need to find out about the driver of the motor. We believe that direct drive motors can provide low enough inertia ratio for PID control; however, we think this is a suboptimal solution.

      • Clarified functional and design requirements

        • Temperature requirements

          • Entire system is subject to temperature bath

        • Design requirements

          • We are allowed to divide up the chip real estate

      • Reorganized test sequence (see Multimedia tab)

2. Goals for next week

• • Redesign the platform to minimize the inertia, torque, and power specifications

  • Determine the optimal materials that can withstand the functional requirements

    • Temperature range

    • Fatigue 

    • Creep

    • Stress

  • Determine motor, controller, and encoder combination that meet the new specifications

3. Instructor comments from last meeting and actions taken

• • Focused on a single kinematic system rather than investigating multiple systems individually

4. Sponsor comments from last meeting and actions taken

• • Made a list of questions regarding the system requirements and forwarded it to Dr. Babcock, who will contact Rasco for further clarification

5. Risks and areas of concern

• • Due to the high torque requirements, the motors we will be choosing will 

  • The system has to withstand the extreme temperature for a long period of time

    • We need to find the right hardware within our budget which can fulfill all the specifications

6. Schedule

• • Finish the advanced machine shop workshop for future fabrication (Jae, Peter, Austin)

  • Finish the redesign of the model and get it approved by the sponsor (All)

  • Determine the appropriate motors/sensor combination for the design (Nathan)

  • Contact the manufacturer to clarify motor driver capabilities (Bruno)

  • Determine the material (All)

  • Estimate aggregate cost (All)

7. Budget

• • Risk Reduction: $215.20 

8. Progress

• • How to rearrange the navigation bar