|Questions Regarding Braking
1. How are the existing vehicle brakes coordinated with the LHI system?
The LHI system simply monitors brake pedal position. The only modification to the brake system is that a very short inactive region of pedal travel is added at the top of the stroke allowing the LHI system to do some or all of the slowing or stopping of the vehicles without using the brakes at all. Aside from the small amount of dead band at the top the brakes work normally. Software controlling the LHI system can detect wheel slippage as well as a panic stop, and in both conditions the brakes function as normal.
2. What happens in case of LHI system malfunction?
Failure of the LHI system has no effect on the operation of the truck or bus. There are three levels of redundancy which prevent the unintended movement (both acceleration or deceleration) of a vehicle because of the LHI system.
3. How does the system handle changes to vehicle dynamic behavior during braking, such as braking while cornering or on slippery or loose surfaces (because of rear-only braking) and while transitioning to service brakes?
As mentioned above, the LHI system can detect wheel slippage and will disable the system when appropriate. Also, the system can detect the potential for slippery conditions and may disable the system if appropriate. Ultimately a driver is responsible for the safe operation of the vehicle by knowing how the hybrid truck or bus will perform.
Questions Regarding the Accumulators
4. What happens when the accumulator becomes fully charged?
When the accumulator is fully charged the controller uses a bypass function to maintain the same braking force on the vehicle without adding more fluid to the accumulator. The maximum setting of this valve will not allow over-pressurization of the high pressure accumulator. Further, the maximum fluid level of the system will not allow the accumulator to be overfilled as the pumps will run out of fluid prior to that event.
Questions Regarding Engine/Transmission control
5. What is being changed from stock on my vehicle to integrate the LHI system?
The LHI system is a “piggy-back” system – meaning that it is simply added to the existing drivetrain without removing or changing any major components. The system routinely gathers information about the vehicle’s operation (such as speed) from the vehicle, in addition to input received from the driver. The LHI control system simply collects that data and uses in its own parallel operating control system.
6. Is the engine shut down while braking?
LHI does not currently employ engine shut down technology—so all auxiliary systems work as stock.
Questions Regarding Driver Control & Feedback
7. Is the system fully automatic? If not, how does the driver control it?
The operator controls the dynamics of the vehicle as they normally would with the brake and accelerator pedals. Although the feel of the vehicle may be slightly different due to increased performance of the brakes and acceleration, the system is designed to be completely transparent to the operator. Most drivers feel the performance changes and adapt their driving style without knowing it. Much the same as you would drive a Porsche Cayenne differently than a Volkswagen Bug.
8. What feedback does the driver get?
The driver gets an integrated dashboard tablet display that shows them the fuel savings they are achieving and the status and efficiency of the regeneration system in real time.
Questions Regarding Service Life and Warranty
9. How reliable is the system? What maintenance is required, and what is the expected lifetime?
The Lightning Hybrids hydraulic hybrid system is based on industrial components used in standard heavy equipment like tractors and industrial machinery. It is designed to be ultra-low maintenance for five years, with one filter change and one bladder change.
10. Will the system void my original manufacturer’s warranty?
No, the system does not negatively interfere with the operation of the vehicle, so your OEM warranty will not be voided.
11. What is Lightning Hybrids’ standard warranty for the system?
Three years and 50,000 miles. Extended warranties are available.
12. How much does the LHI system weigh?
The system weighs about 450 lbs.
13. Are there grant and tax incentives available for the LHI system?
Yes. The LHI system qualifies for a variety of grants and incentives at the local and national levels. LHI can assist you in finding and applying for funding when appropriate.
Video: Dashboard Monitor
Frequently Asked Questions about Our Hydraulic Hybrid System