Forward / Reverse Switch

The vehicle comes to a controlled stop exactly the same as if the accelerator has been released, and then begins to move in reverse.

As above, if the vehicle is slowing because the accelerator has been released, it continues a controlled brake, and then stops completely before engaging reverse.

Yes – except that the motor is “tuned” differently for forward and reverse, and has different limits imposed on it so that the maximum speed in reverse is less than the maximum possible speed in drive.

Correct – this is adjusted via the ‘proportional integral derivative’ (PID) tuning of the motor. In general, the regenerative braking effect reduces as the vehicle speed approaches zero. If the opposite direction of travel is selected, then the braking action is sustained.

There is no need. Especially with low speed maneuvering, it is a desirable feature to be able to switch direction of travel at any time.

Yes, Voltra could provide this, but it would not dramatically change the actual behaviour of the vehicle. It would still come to a controlled stop and then go into reverse (because reverse is selected). The only difference is that if the vehicle is in reverse, the regenerative braking is higher as the vehicle speed approaches zero.

Regenerative braking

The electric motor is a motor/generator. It has the same power characteristics whether operating as a motor or as a generator and is direction of rotation agnostic. The control of the motor is via dynamic adjustment of the torque, which can be either a positive (driving) or negative (generating) value. The torque control is via a feedback loop being a ‘proportional integral derivative’ (PID) control algorithm. The motor/generator torque values are recalculated every 2 – 10 milliseconds.

Yes – that’s what it does now, no change required. The vehicle speed, whether driving or regenerating, is set by the throttle position. A variation in the speed relative to the throttle position when going uphill versus downhill will be present, as this is the value of the positive or negative value in the PID error. This difference in speed will not be detectable by any human operator.

Software

Data available includes: Position (GPS dependent), vehicle speed, condition of all electrical subsystems, temperatures of all cell groups, voltage of all cells, motor torque, motor RPM, battery capacity, odometer value, energy use driving, energy from charger, energy used for the A/C, park brake status, throttle position, drive selection, charger status, charger charge current and voltage, Diagnostic Trouble Codes (DTC)

Other software features include: speed/power/torque limiting, charging status, location, ability to remotely disable, ability to update most vehicle software remotely, ability to link to fleet management systems, and vehicle operating history.