Week 1

(1/9/12-1/13/12) 

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

   1. • Delegation of the individual component analysis

        • Linear actuators (Bruno)

        • Motor analysis (Peter)

        • Control systems (Nathan)

        • Sensor analysis (Jae)

        • Slip ring and wiring method (Austin)

2. Goals for next week

   1. • Modify the prototype to be presentable to our sponsor. The two inner rings in our prototype need to be able to rotate completely (at least 360 degrees) and independently of each other. We will not be concerned with slip rings, time contraints, and the third degree of freedom.

        • Gear changes to get more torque is achieved (Bruno)

        • Optimize the control systems so that both rings of the gimbal (Nathan)

        • Fabrication and modification of the prototype (Jae, Peter, and Austin)

      • Speak to Dr. Babcock about certain requirements

        • Weight requirements: the platform has been defined as 3kg. For a factor of safety, we have assumed 8kg. We need the sponsor to specify how heavy the platform is and what will potentially be mounted on it (e.g. size and weight of MEMS, DAC, and battery)

        • Platform thickness parameter: although the area of the broad side of the platform has been defined, the thickness of it will allow us to make modifications to our design.

        • Temperature requirement: A temperature range has been broadly defined as -60C to 160C. We are not sure if the platform has to operate at this temperature, or the entire device, moreover, we wish to understand why the platform/device must operate at these extreme temperatures and whether it is our responsibility to find a batter that will operate at these temperatures.

3. Instructor comments from last meeting and actions taken

   1. • Research closed chain systems, namely the Stewart platform and linear actuators

        • For linear actuators, electric actuators are too expensive, pneumatic actuators are not precise enough and less responsive. Although hydraulic actuators are cost effective and powerful, but they require an external reservoir and pump, are noise, and prone to leakage.

        • Stewart platform has a limited range of motion, a mere 11 degrees of motion on a single axis

        • Closed chain system as a feasible alternative is eliminated

4. Risks and areas of concern

   1. • Inertia of gimbal system

        • Motor requirements: motors are likely to be very heavy, some estimates put it at around 5kg. Thus, adding a significant amount of weight to only one side of the platform. One option is to mount the sensor part of the servo motor to the opposite joint of the gimbal to balance the weight

      • Accuracy of controls system

        • Since allowable tolerance is under 2%, the accuracy of the controls system will be crucial to the success of our design. Selection of a servo motor and coding of said motor will determine the accuracy of our device.

5. Schedule

   1. • Advance machine shop workshop (Austin, Jae, Peter)

      • Human Interface Design (Bruno, Nathan)

      • Speak to our sponsor (Babcock) on Tuesday

      • Speak to our instructor (Delson) on Wednesday

6. Budget

   1. • Acrylic: $215.00

      • Total budget: $3500.00

7. Progress

   1. • Created a template and theme