Thesis Student : Shuttle mechanical optimization

Job Description

Problem: Currently most shuttles are designed with components sized to gut feeling. In order to optimize the components and make sure they are not over or under designed an FEA analysis of the component should be done to estimate fatigue life. In order to do an FEA analysis accurate load information is critical.

Main issues: Vehicle loads in different situations, the distribution of loads into the sub assemblies, and motor forces are not well understood/documented today.

Solution idea: A load cycle should be built showing the different load conditions a shuttle is subject to, with a corresponding duty cycle (which % of life is the shuttle exposed to which load) and motor loads. This can be done for various different applications (different types of loads). The load applied on the full shuttle should then be broken down into its load path to understand how the sub-assemblies and individual components are loaded. Histograms of load speed and acceleration would be beneficial. If time permits, these load cycles should be validated (experimental measurements of shuttles in different situations). If time permits the sub-assemblies/sub-components individual loads should be measured (load cells and/or strain gauges).

Short description:

For example on the 1D shuttle moving regular pallets, this would be something like

-Empty load : 45% of life, lift motor speed, acceleration and torque = XXX, drive motor speed, acceleration and torque = YYY

-Medium load: 10% of life, lift motor speed, acceleration and torque = XXX, drive motor speed, acceleration and torque = YYY

-Max load: 35% of life, lift motor speed, acceleration and torque = XXX, drive motor speed, acceleration and torque = YYY

-Overload: 10%, lift motor speed, acceleration and torque = XXX, drive motor speed, acceleration and torque = YYY

-Pallet is centrally loaded 80% of the time, the other 20% it applies 60% of the load on the left side