Kenworth — Design-for-Assembly Training Cart

During my Kenworth internship, I designed and built a modular cart for transporting design-for-assembly training materials. The cart disassembled into manageable sections that all fit inside a single shipping box. The training materials traveled in separate boxes, and the cart assembled without tools in under a minute.

I led the project from gathering end-user requirements through concept development, detailed CAD, design reviews, and assembly. I coordinated with the research and development team to have the parts manufactured and assembled the finished cart myself.

Kenworth’s design-for-assembly training used large sheet-metal box kits to demonstrate how design choices affect assembly. Participants worked with deliberately difficult-to-assemble kits and compared them with an improved design. Smaller demonstrations introduced additional assembly principles.

The existing utility cart was overcrowded and lacked organization. Loading materials into a vehicle was time-consuming, individual kits were difficult to access, and the setup was unsuitable for long-distance shipping. Expanding the training to additional plants required a better transport and storage solution.

I organized meetings with trainers and other end users to understand their needs and translate them into design requirements.

• Keep each manual lift below Kenworth’s 35-pound ergonomic limit.
• Allow one person to load, unload, and maneuver the system.
• Organize materials for easy access to individual training kits.
• Support shipping between plants.
• Provide durability for repeated use and adaptability as training materials changed.
• Meet the project’s budget and schedule.
• Demonstrate design-for-assembly principles in the cart’s own construction.

I used a first-principles approach to distinguish the underlying requirement from an assumed solution: the entire cart did not need to weigh less than 35 pounds—each manual lift did.

This opened up different approaches to loading and transport. One concept used a hydraulic lift-and-transfer mechanism inspired by ambulance stretchers, while others divided the system into smaller loads.

I gathered ideas from coworkers and used a weighted decision matrix to compare concepts against the design requirements. A concept review with multiple levels of management narrowed the options to two. I developed both in CAD to investigate their feasibility in greater detail, then held a second review to select the final approach.

The final design used a sheet-metal frame divided into four sections, connected by PETG 3D-printed snap latches. The handle separated into three sections. Heavy-duty ULINE boxes held the training kits, with custom 3D-printed internal dividers to organize the materials.

An additional box stored beneath the assembled cart served as its shipping container. When disassembled, all sections of the cart fit inside that single shipping box. The training kits traveled in separate boxes.

The complete cart exceeded 35 pounds, but separating it into modules kept each individual packed load below the lifting limit. The latch system allowed the cart to be assembled in under a minute without tools.

I refined the detailed CAD through design reviews, worked with the research and development team to manufacture the parts, and assembled the cart myself.

Before my internship ended, I observed it being used in a training session. It performed well during that initial use, and the trainers reported that it made the session run more smoothly.

Long-term durability and shipping performance were not validated during my internship.

This project reinforced the value of a first-principles approach: defining the actual need before committing to a solution. Reframing the weight constraint around individual lifts allowed me to explore mechanical assistance and modularity rather than simply reducing the weight of a single cart. The selected modular approach addressed both safe loading and shipping.

Participating in the design-for-assembly training and applying feedback to my own design also strengthened my understanding of simplicity, assembly, and usability. Carrying the project from end-user conversations through manufacturing and initial use showed me how those considerations shape a practical engineering solution.