Abstract: An energy storage module for use in an electric vehicle, such as a lift truck, is disclosed. The energy storage module includes a bank of super capacitors or ultra-capacitors which are connected between the battery and the load. In operation, the energy storage module charges the capacitors, and uses the charged capacitors to level the load on the battery, limiting spikes in current draw, and assuring a substantially smooth discharge profile, wherein the battery discharge is substantially steady state. The energy storage module further includes sensors for determining when the battery and load are connected.

Abstract: Wear of a pump is estimated using a process that involves operating the pump to drive a hydraulic actuator that moves a member. The actual speed of the member is determined and the speed of the pump is sensed. Pressure of fluid conveyed from the pump to the hydraulic actuator also is sensed. A predicted speed of the member is calculated based on the speed of the pump and the pressure of the fluid. The predicted speed is compared to the actual speed and the result is employed to provide an indication of a degree of wear of the pump. The difference between the predicted speed and the actual speed increases as the pump wear increases.

Abstract: A system and method that maintains the dynamic stability of a material handling vehicle having a vertical lift. The method allows static vehicle properties, such as vehicle weight, wheelbase length, and wheel configuration, and dynamic operating parameters, such as vehicle velocity, floor grade, lift position, and load weight, to be accounted for when maintaining the dynamic stability of a moving material handling vehicle. The method may include calculating and predicting center-of-gravity parameters, wheel loads, and projected force vectors multiple times a second and adjusting vehicle operating parameters in response thereto to maintain vehicle stability.

Abstract: A method for counting the pallets or loads moved by a lift truck using internal sensors is disclosed. The lift truck includes a weight sensor for weighing a load, a height sensor, for measuring a height of the forks, and a distance sensor for determining whether the vehicle has moved. When the data from each of these sensors exceeds a corresponding minimum value, a vehicle control system increments a pallet counter. A count of the number of pallets moved is therefore maintained without the need for tracking specific pallets of for adding expensive components and devices.

Abstract: Wear of a pump is estimated using a process that involves operating the pump to drive a hydraulic actuator that moves a member. The actual speed of the member is determined and the speed of the pump is sensed. Pressure of fluid conveyed from the pump to the hydraulic actuator also is sensed. A predicted speed of the member is calculated based on the speed of the pump and the pressure of the fluid. The predicted speed is compared to the actual speed and the result is employed to provide an indication of a degree of wear of the pump. The difference between the predicted speed and the actual speed increases as the pump wear increases.

Abstract: A system and method that maintains the dynamic stability of a material handling vehicle having a vertical lift. The method allows static vehicle properties, such as vehicle weight, wheelbase length, and wheel configuration, and dynamic operating parameters, such as vehicle velocity, floor grade, lift position, and load weight, to be accounted for when maintaining the dynamic stability of a moving material handling vehicle. The method may include calculating and predicting center-of-gravity parameters, wheel loads, and projected force vectors multiple times a second and adjusting vehicle operating parameters in response thereto to maintain vehicle stability.

Abstract: An energy storage module for use in an electric vehicle, such as a lift truck, is disclosed. The energy storage module includes a bank of super capacitors or ultra-capacitors which are connected between the battery and the load. In operation, the energy storage module charges the capacitors, and uses the charged capacitors to level the load on the battery, limiting spikes in current draw, and assuring a substantially smooth discharge profile, wherein the battery discharge is substantially steady state. The energy storage module further includes sensors for determining when the battery and load are connected.

Abstract: A method for counting the pallets or loads moved by a lift truck using internal sensors is disclosed. The lift truck includes a weight sensor for weighing a load, a height sensor, for measuring a height of the forks, and a distance sensor for determining whether the vehicle has moved. When the data from each of these sensors exceeds a corresponding minimum value, a vehicle control system increments a pallet counter. A count of the number of pallets moved is therefore maintained without the need for tracking specific pallets of for adding expensive components and devices.

Abstract: A state-of-charge indicator system monitors the battery current and voltage during operation of a lift truck. Selected current and voltage samples are used to calculate the internal battery resistance and this is employed to calculate a “dynamic” battery voltage. This dynamic battery voltage is used as input to a stored look-up table which provides a battery state-of-charge value.