THE ULTIMATE TAILGATESENIOR DESIGN: P10811

High Level Design•Meets or exceeds functions and capacities of stock tailgate•Provide a flat work surface for the end user•Provide a main feature clamp and auxiliary clamp•Include two storage bins•Include electrical power to the tailgate attachment•Ensuring electrical power is delivered in a safe and secure manner that will not damage the current vehicle•Provide a battery saving function dependent upon the vehicle’s current state

Electrical-12 VDC accessory outlet-Two 120VAC three prong outlets-Drop of max current to 67% to save battery when truck is off-Safety and security shutoff conditions for:

-Vehicle start-Gear shifting out of park

-Low vehicle battery-Overload

Acknowledgements: Special thanks to Chris DeMinco, Dr. Mark McVea, Dr. Chris Hoople, and Mike Hargrave for their assistance and guidance in the design and implementation of this product

Detailed Features

Mechanical and Structural Design

Electrical Power System Design

ObjectiveThe purpose of the Ultimate Tailgate Project is to take the wasted space in a stock pickup truck tailgate and turn it into a useful, completely stocked workbench. The specifications outlined in this project incorporate a prototype version of this product, with intent to easily convert to a production version at a later date. As a result the specifications are proof of concept based and do not include regulations for the Department of Transportation (DOT) or the Federal Motor Vehicle Safety Standards and Regulations (FMVSS). The final product is a fully functioning, aesthetically pleasing tailgate for a 2001 Chevrolet Silverado 2500.

Workmate Style Clamp

Electrical Housing

Storage Drawers

Auxiliary Clamp Pocket

Jonathan Brooks (ME and PM) Matthew Piatkowski (ME) Spencer Herendeen (EE)

System Breakdown Hierarchy

The Team (L-R): Spencer Herendeen (EE)Jonathan Brooks (ME and Project Manager)Matthew Piatkowski (ME)

Mechanical-Flat work surface capable of supporting 500 lb-Tailgate surface level with floor of truck bed-Workmate style clamping device-Incorporated bar clamp-Two storage drawers with 50 lb load capacity each-Matches up to stock tailgate mounting points for easy installation

The tailgate electrical system was implemented using a 2000 W power inverter from the Whistler Group. This inverter provided the necessary power and safety protections to lead to the decision for the inverter to not be self-designed. This inverter was thoroughly tested to ensure ideal characteristics and proved at 96% efficiency under a load of 2/3 of the maximum.

The safety lockout conditions were implemented using a set of relays to ensure that the power output was only active when the vehicle was in park or neutral (when the gear relay was engaged). This provides a quick switching of approximately 1 s. The set of relays also switches between a lower and higher power mode. This mode will limit the output current to 10 A when the truck is off (relay is not engaged) and 15 A when the truck is on (relay is engaged). This current is limited by a breaker which shuts off at a nominal 10 A.

The system is also provided with a LED bank to indicate to the end user whether the system power is on, and what current mode the system is currently in. The current leading to the LEDs was limited using an appropriate valued resistor.

The tailgate main structure is constructed from a mild steel square tube structure. Individual components are MIG welded together to ensure sufficient strength to withstand a strenuous work environment.

Features incorporated into the tailgate include:•Black and Decker Workmate style clamping mechanism•Two removable, modular storage drawers , each with a 50 lb load capacity•An Auxiliary one-handed bar clamp, mountable to the tailgate frame•A self actuation mechanism, consisting of two electric motors with gear reduction to allow for automated raising and lowering of the tailgate