Electric rail vehicle

1. An electric rail vehicle comprising:

a bogie frame defining a longitudinal axis and a lateral axis perpendicular to the longitudinal axis, the bogie frame having a stiffness mismatch between the lateral and longitudinal axes;

a set of bumpers mounted to the bogie frame, the set of bumpers comprising an abutment surface at a maximal extent of the electric rail vehicle along the longitudinal axis;

a payload interface configured to mount a cargo payload to the electric rail vehicle;

a bolster bowl rotatably mounting the payload interface to the bogie frame;

a plurality of suspension elements coupling the payload interface and the bogie frame which are symmetrically distributed relative to a midsagittal plane of the bogie frame;

an electric powertrain mounted to the bogie frame and comprising a plurality of rail wheels;

a battery electrically coupled to the electric powertrain;

a set of sensors mounted to the bogie frame, the set of sensors comprising: a bumper feedback sensor and a GPS sensor; and

a vehicle controller mechanically coupled to the bogie frame and configured to autonomously control the electric powertrain based on measurements from the set of sensors.

2. The electric rail vehicle of claim 1 , wherein the set of bumpers comprises a pair of bumpers arranged at opposite ends of the bogie frame along the longitudinal axis.

3. The electric rail vehicle of claim 1 , wherein each bumper comprises bumper suspension defining a compression axis parallel to the longitudinal axis, wherein the bumper feedback sensor is coupled to the bumper suspension and configured to measure an axial compressive force along the compression axis.

4. The electric rail vehicle of claim 3 , wherein the bumper feedback sensor comprises a load cell.

5. The electric rail vehicle of claim 3 , wherein the vehicle controller is configured to autonomously control a motor of the electric powertrain based on the axial compressive force along the compression axis.

6. The electric rail vehicle of claim 1 , wherein the set of sensors further comprises a camera and a set of range imaging sensors, the set of range imaging sensors comprising a LIDAR or a Radar.

7. The electric rail vehicle of claim 1 , further comprising:

a set of hydraulic brakes; and

a set of electromechanically actuatable parking brakes;

wherein the electric powertrain is configured to dynamically harvest energy by regenerative braking.

8. The electric rail vehicle of claim 1 , wherein the plurality of suspension elements comprise: an anti-roll bar; a pair of nested coil springs; a set of chevron springs aligned with an axis of the pair of nested coil springs; and a damper.

9. The electric rail vehicle of claim 1 , wherein a torsional stiffness about the lateral axis is at least triple a torsional stiffness about the longitudinal axis.

10. The electric rail vehicle of claim 1 , wherein the stiffness mismatch of the bogie frame comprises: greater torsional compliance along the longitudinal axis and greater spanwise rigidity parallel to the lateral axis.

11. The electric rail vehicle of claim 1 , wherein the plurality of rail wheels defines a first axle and a second axle, wherein a torsional stiffness of the bogie frame about the longitudinal axis between the first and second axles is between 500,000 in*lbf/deg and 1,500,000 in*lbf/deg.

12. A rail system for autonomously transporting a cargo container, the rail system comprising:

a pair of autonomous bogies, each bogie of the pair comprising:

a payload interface, the cargo container removably mounted to the payload interface;

a bogie frame defining a longitudinal axis and a lateral axis perpendicular to the longitudinal axis, wherein the bogie frame is more torsionally compliant about the longitudinal axis than about the lateral axis;

a set of bumpers mounted to the bogie frame, the set of bumpers comprising an outboard bumper comprising an abutment surface at a maximal vehicle extent along the longitudinal axis and extending beyond the cargo container along the longitudinal axis;

a bolster bowl rotatably mounting the payload interface to the bogie frame;

a plurality of suspension elements coupling the payload interface and the bogie frame which are symmetrically distributed relative to a midsagittal plane of the bogie frame;

an electric powertrain mounted to the bogie frame and comprising a plurality of rail wheels;

a battery electrically coupled to the electric powertrain; and

a bumper feedback sensor coupled to the outboard bumper and configured to measure compressive force at the outboard bumper.

13. The rail system of claim 12 , wherein the bumper comprises bumper suspension defining a compression axis parallel to the longitudinal axis, wherein the bumper feedback sensor is coupled to the bumper suspension and configured to measure an axial compressive force along the compression axis, wherein a vehicle controller of a first bogie of the pair is configured to autonomously control a motor of the electric powertrain based on the axial compressive force along the compression axis.

14. The rail system of claim 12 , wherein each bogie further comprises a GPS sensor arranged beneath a base plane of the cargo container.

15. The rail system of claim 12 , wherein a first bogie of the pair further comprises a camera and a range sensor oriented towards a second bogie of the pair.

16. The rail system of claim 12 , wherein each bogie of the pair further comprises a second bumper opposite the outboard bumper along the longitudinal axis.

17. The rail system of claim 12 , wherein a longitudinal length of each bogie is less than 12 feet.