USPS Retrofit Project
Long Live the Long Life Vehicle
From LLV to eLLV.
The program is like so:
Take a dozen LLVs from the USPS in varying degrees of state of repair. Retrofit using two methods:
1. A custom-fit BEV skateboard from Canoo, taken from their initial design. The body of the LLV would either be refurbished or remade to accommodate any structural needs of the skateboard, without substantially altering interior design. Examine whether a cargo modularization system would improve loading and unloading.
2. An implementation of Lordstown/Skaphe in-hub wheel motors. Take out the old engine and drivetrain and implement a drive-by-wire system. As a prototype, offer hybridization through either a hydrogen fuel cell system or traditional diesel /gasoline system, doubling as a generator for niche use cases where the route plan exceeds the designed operating range.
The aim of the prototype stage is to assess feasibility, cost, time-to-implement, and performance.
Feasibility study:
- assess the mechanical alteration requirements of the skateboard chassis and LLV body frame to successfully complete the integration between the two.
- construct a wiring harness system and structural dash replacement for steering and electronics
- do a comparative analysis between Canoo and Lordstown/Skaphe solutions
The retrofit process involves three primary procedural elements:
1. Collect the 100,000+ LLVs from around the nation.
This process, as conceptualized, requires receiving delivery or taking possession of USPS LLVs from jurisdictional fleets while ensuring those fleets can keep up with operational demands. Whether this entails replacing the LLV on a 1-to-1 rate at the time of exchange, arranging through the organizational body of the USPS to purchase and distribute vehicles in anticipation of the loss of the LLV from the fleet, or taking a sufficient supply of excess vehicles and going through one jurisdiction at a time through a 1-to-1 exchange, the aim is to ensure smooth operation and seamless reintegration of service vehicles.
Moving from purely gasoline-powered or hybrid USPS vehicles requires an investment in EV infrastructure that should precede or coincide with with the rollout of EVs.
In principle, the eLLV project is best suited for urban environments, and the vehicle could be kept in service arguably forever. Should this "life-extending" retrofit project merely serve as a stopgap, after about 7 years, LLVs requiring a mandatory battery exchange would be transitioned instead to the rural postal system to be used to supplement or replace the civilian fleet of consumer-grade minivans and station wagons. Some portion could be retrofitted again for donation to the Vehicles for Veterans program, fitted with wheelchair lifts and locks and panel windows.
This timeframe considers primarily the anticipated reliable life of Lithium-based battery packs, which is the dominant method of energy storage at present. The aim would be to, at that 7-year mark, replace the Lithium-based pack with solid-state batteries, further improving the weight baseline of the LLV, thus improving the cost-to-benefit analysis as it pertains to energy use/cost over the long term.
2. Strip and Teardown the LLV for Refurbishment
Remove all internal components.
Isolate the aluminum body frame.
Paint-strip the body, and perform rust and damage refurbishment.
Reconstitute the body frame, replacing/welding as necessary.
Paint and seal the body.
3. Rebuild the LLV as an eLLV
According to the methods from above, rebuild the chassis frame, integrate wiring, battery, and electronics elements into the eLLV body, and mount the body to the BEV chassis.
The essential wholesale retrofit process of operational and idle LLVs involves several key phases:
1. Rotate out old LLVs with new product expeditiously.
This sequence requires replacement vehicles to be on-hand.
2. Process intake vehicles at scale.
This approach requires up to four central processing facilities oriented around the large-batch dipping/stripping of body frames, and consolidation of LLV parts. LLVs can be assembled in batches regionally, then transferred to the centralized site for bulk processing, on a phased schedule. As disassembly is a manual process with a traditional mechanic's or welder's level of experience, this can be performed in whatever way is deemed suitable, but oriented around original analysis of "time-to-disassemble", with diagrammatic disassembly instructions and educational videos to facilitate the process and protect any particular components.
Upon arriving at the centralized site by car carrier and/or train, the LLV is registered with a transfer log tracking origins. Internal components are segregated and assessed for repurposing / resale or scrap. A generalized assessment log of the state of repair will be generated, with notation of any anomalous features, which can subsequently used to make assessments about environmental factors and mitigation measures (undercarriage powdercoating, graphenated sealant, fender enhancement, et cetera).
eLLV Thermal Management
eLLV Thermal Management Solutions
As part of the LLV retrofit process, there are certain potential changes that would allow the box-on-wheels to improve overall performance and address safety concerns.
1. Flettner Vent Air Circulation
The Flettner vent is a top-mount rotating passive fan that intakes air as air motion forces the vent fan to rotate. This effectively serves to circulate interior hot air by forcing in cooler outside air while expelling hot cabin air.
2. Filtered Air Intake Routing
Depending on the configuration of the dash, air can be circulated by integrated fan intake or passive motion-induced intake, directing air from the front of the vehicle through a filter and into the cabin at abdomen level, in addressing the newest safety conditions for USPS drivers. Drivers are required to maintain a particular body temperature on the basis of the NGDV RFP. While non-A/C circulation methods are not the same as full power coolant-based systems, hybridization of coolant-plus-passive-air circulation can potentially significantly reduce thermal strain on drivers.
3. Residual Battery Heat Recirculation
Lithium Batteries produce heat and require some amount of active cooling. In colder climates, heating can also be an issue, particularly for initial start. In general, the heating and cooling requirements can be directed into the cabin as residual heat from the system, or could theoretically be diverted/oversized for the purpose of cabin Air Conditioning.
4. Advanced Windshield
USPS plate windshields are standard pieces of equipment for the LLV but can be upgraded within the same form-factor to reduce solar radiation affecting drivers and heating the cabin area. This can be done by adding improved radiation dispersal materials or adding additional reflectors.
5. GPS and Communications Electronics
As part of the technology upgrade associated with the EV electronics, additional sensors and connectivity to cellular data networks can be employed for the purposes of vehicle tracking and data analytics. This data can be employed to supplement existing data for the purpose of narrowing NGDV requirements for a given region.
In addition, onboard sensors addressing internal temperature concerns for the purpose of protecting electronics can be employed to track and warn regarding extreme temperatures, and can be employed in that way to direct driver to shade or cover, or dynamically adjust aforementioned technical solutions. These methods might indicate a need to roll up windows to temporarily direct onboard cooling/heating elements to adequately raise/reduce temperatures as needed.
