Granted Patent B2

US 12,728,729 · App. 18/233,555 · Granted Sep 8, 2026

Inventors: Gregory August Theodosakis (Martinez, GA); Russell William King (Evans, GA); Jonathan Daniel Bowen (North Augusta, SC)

Assignee: TEXTRON INNOVATIONS, INC

B60L15/10B60L7/14B60L50/60B60L58/12B60L2200/22B60L2240/12B60L2240/16G01C9/08

Abstract

Claims (83)

1 . A method of controlling a utility vehicle, the method comprising:

initially setting a maximum speed constraint imposed on the utility vehicle to an initial value;

receiving a state of charge signal that indicates a current state of charge of a lithium battery which provides electric power for utility vehicle propulsion; and

based on the state of charge signal that indicates the current state of charge of the lithium battery, adjusting the maximum speed constraint imposed on the utility vehicle from the initial value to an adjusted value that is different from the initial value;

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing an incline assessment operation that indicates whether the utility vehicle is currently traveling down an incline to prevent the maximum speed constraint imposed on the utility vehicle from being lowered from a first speed limit to a second speed limit unless the utility vehicle is currently traveling down an incline;

wherein the utility vehicle includes an electric motor that provides utility vehicle propulsion;

wherein performing the incline assessment operation includes:

providing an incline assessment operation result indicating that the utility vehicle is traveling front-to-back down the incline in response to the electric motor rotating in a predefined direction and regenerating an amount of energy that exceeds an energy regeneration threshold;

wherein the initial value is the first speed limit;

wherein the adjusted value is the second speed limit that is slower than the first speed limit;

wherein adjusting the maximum speed constraint imposed on the utility vehicle includes:

lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit; and

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing a comparison operation that compares the current state of charge of the lithium battery indicated by the state of charge signal to a predefined state of charge threshold for the lithium battery, a result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery, the maximum speed constraint for the utility vehicle being lowered from the first speed limit to the second speed limit in response to the result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery.

2 . The method of claim 1 wherein the utility vehicle includes a set of inertial measurement units (IMUs); and

wherein providing the incline assessment operation result occurs in response to a set of output signals from the set of IMUs.

3 . The method of claim 1 wherein the utility vehicle includes an accelerator pedal and a motor controller coupled with the accelerator pedal, the motor controller initially mapping angular deflection of the accelerator pedal to a first linear utility vehicle propulsion response from zero to the first speed limit; and

wherein lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit includes:

remapping the angular deflection of the accelerator pedal to a second linear utility vehicle propulsion response from zero to the second speed limit in place of the first linear utility vehicle propulsion response.

4 . The method of claim 1 wherein a current speed of the utility vehicle is lower than the first speed limit and higher than the second speed limit; and

wherein the method further comprises:

slowing the utility vehicle from the current speed to at least a rate of the second speed limit in response to lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit.

5 . The method of claim 1 wherein a current speed of the utility vehicle is lower than the first speed limit and the second speed limit; and

wherein the method further comprises:

maintaining the current speed of the utility vehicle below the second speed limit.

6 . The method of claim 1 wherein the utility vehicle includes a battery management system (BMS) coupled with the lithium battery, the state of charge signal that indicates the current state of charge of the lithium battery being received from the BMS; and

wherein the method further comprises:

receiving a current voltage signal that indicates a current voltage of the lithium battery, the current voltage signal being different from the state of charge signal that indicates the current state of charge of the lithium battery.

7 . Electronic circuitry to control a utility vehicle, the electronic circuitry comprising:

a battery system interface; and

a controller coupled with the battery system interface, the controller being constructed and arranged to perform a method of:

initially setting a maximum speed constraint imposed on the utility vehicle to an initial value,

receiving, through the battery system interface, a state of charge signal that indicates a current state of charge of a lithium battery which provides electric power for utility vehicle propulsion, and

based on the state of charge signal that indicates the current state of charge of the lithium battery, adjusting the maximum speed constraint imposed on the utility vehicle from the initial value to an adjusted value that is different from the initial value;

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing an incline assessment operation that indicates whether the utility vehicle is currently traveling down an incline to prevent the maximum speed constraint imposed on the utility vehicle from being lowered from a first speed limit to a second speed limit unless the utility vehicle is currently traveling down an incline;

wherein the utility vehicle includes an electric motor constructed and arranged to provide utility vehicle propulsion;

wherein performing the incline assessment operation includes:

providing an incline assessment operation result indicating that the utility vehicle is traveling front-to-back down the incline in response to the electric motor rotating in a predefined direction and regenerating an amount of energy that exceeds an energy regeneration threshold;

wherein the initial value is the first speed limit;

wherein the adjusted value is the second speed limit that is slower than the first speed limit;

wherein adjusting the maximum speed constraint imposed on the utility vehicle includes:

lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit; and

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing a comparison operation that compares the current state of charge of the lithium battery indicated by the state of charge signal to a predefined state of charge threshold for the lithium battery, a result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery, the maximum speed constraint for the utility vehicle being lowered from the first speed limit to the second speed limit in response to the result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery.

8 . The electronic circuitry as in claim 7 wherein the battery system interface is constructed and arranged to receive the state of charge signal that indicates the current state of charge of the lithium battery from a battery management system (BMS) coupled with the lithium battery; and

wherein the method further comprises:

receiving, through the battery system interface, a current voltage signal that indicates a current voltage of the lithium battery, the current voltage signal being different from the state of charge signal that indicates the current state of charge of the lithium battery.

9 . The electronic circuitry as in claim 7 wherein a current speed of the utility vehicle is lower than the first speed limit and higher than the second speed limit; and

wherein the method further comprises:

slowing the utility vehicle from the current speed to at least a rate of the second speed limit in response to lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit.

10 . The electronic circuitry as in claim 7 wherein a current speed of the utility vehicle is lower than the first speed limit and the second speed limit; and

wherein the method further comprises:

maintaining the current speed of the utility vehicle below the second speed limit.

11 . A utility vehicle, comprising:

a battery management system (BMS) having a lithium battery;

a utility vehicle propulsion system constructed and arranged to provide utility vehicle propulsion using electric power from the lithium battery; and

electronic circuitry coupled with the BMS and the utility vehicle propulsion system, the electronic circuitry being constructed and arranged to perform a method of:

initially setting a maximum speed constraint imposed on the utility vehicle to an initial value,

receiving, from the BMS, a state of charge signal that indicates a current state of charge of the lithium battery which provides electric power for utility vehicle propulsion, and

based on the state of charge signal that indicates the current state of charge of the lithium battery, adjusting the maximum speed constraint imposed on the utility vehicle from the initial value to an adjusted value that is different from the initial value;

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing an incline assessment operation that indicates whether the utility vehicle is currently traveling down an incline to prevent the maximum speed constraint imposed on the utility vehicle from being lowered from a first speed limit to a second speed limit unless the utility vehicle is currently traveling down an incline;

wherein the utility vehicle propulsion system includes an electric motor constructed and arranged to provide the utility vehicle propulsion; and

wherein performing the incline assessment operation includes:

providing an incline assessment operation result indicating that the utility vehicle is traveling front-to-back down the incline in response to the electric motor rotating in a predefined direction and regenerating an amount of energy that exceeds an energy regeneration threshold;

wherein the initial value is the first speed limit;

wherein the adjusted value is the second speed limit that is slower than the first speed limit;

wherein adjusting the maximum speed constraint imposed on the utility vehicle includes:

lowering the maximum speed constraint imposed on the utility vehicle from the first speed limit to the second speed limit; and

wherein adjusting the maximum speed constraint imposed on the utility vehicle further includes:

performing a comparison operation that compares the current state of charge of the lithium battery indicated by the state of charge signal to a predefined state of charge threshold for the lithium battery, a result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery, the maximum speed constraint for the utility vehicle being lowered from the first speed limit to the second speed limit in response to the result of the comparison operation indicating that the current state of charge of the lithium battery exceeds the predefined state of charge threshold for the lithium battery.

12 . The utility vehicle of claim 11 , further comprising:

a set of ground engagement members;

wherein the electric motor is further constructed and arranged to operate the set of ground engagement members, and

a motor controller coupled with the electronic circuitry, the motor controller being constructed and arranged to control the electric motor;

wherein the motor controller includes a set of inertial measurement units (IMUs); and

wherein the incline assessment operation result is based on input from the set of IMUs.

13 . The method of claim 1 , wherein adjusting the maximum speed constraint imposed on the utility vehicle includes:

decreasing the maximum speed constraint based on the state of charge signal indicating that the current state of charge has reached a predefined state of charge threshold, the current state of charge being a percentage of a full charge of the lithium battery.

14 . The method of claim 1 wherein adjusting the maximum speed constraint further includes:

lowering the maximum speed constraint in response to detecting that the state of charge signal exceeds a predefined state of charge threshold and the incline assessment operation result indicating that the utility vehicle is traveling front-to-back down the incline.

Assignments (2)

Continuity (1)

References Cited (65)