This Small Business Innovation Research (SBIR) Phase II project proposes to develop a fully functional turnkey regenerative semi-active shock absorber for heavy-duty transit buses and other commercial vehicles. An appreciable amount of energy is lost in a typical suspension as heat, especially in heavy vehicles. Existing technologies have been unable to efficiently capture this energy in a cost-effective manner. This project entails hydraulic and electronic model optimization, design of vehicle-ready prototypes, fabrication, lab testing, installation, and operational testing of a hydraulic adaptive damping energy harvesting system. The objective of the project is to demonstrate real-world benefits of an efficient, adjustable damping regenerative shock absorber on a transit bus in operation with a municipal transit agency. Emphasis will be on efficiency improvements, semi-active ride control, and application specific integration requirements to ensure seamless installation and operation. Work will culminate in a fully fielded pilot demonstration and quantification of regenerated energy (improved fuel efficiency) and ride improvement benefits using the regenerative semi-active shock absorber.

The broader impact/commercial potential of this project is significant if the challenges of inexpensively, reliably, and efficiently capturing suspension energy are overcome. The technology has the potential to save millions of dollars per year in fuel for large fleets, and significantly reduce carbon emissions in the United States and abroad. Effectively incorporating an aftermarket or OEM retrofit-able regenerative energy capture system may open doors to many new regenerative technologies in the transportation and automotive sector, facilitating significant reductions in waste energy. In addition, the research may lead to enabling technology for compact, sealed, and efficient hydraulic actuators and energy harvesters across several industrial applications. This may have applications in other fields such as off grid marine (hydrokinetic) energy, aerospace actuators, heavy machinery dampers, orthotics/prosthetics, and robotics.

Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Levant Power Corporation
United States
Zip Code