How well does Aptera track?

[Pistonboy]

This is interesting. Could you please post what video you are referring to? Alphas are mostly display vehicles and not expected to drive well. Betas are experimental vehicles seen on the track where steering and suspension experiments were being performed. Are you referring to the times they took Betas around the industrial park to give select people a ride?

[jared-cormier]

I don’t think torque vectoring has been implemented in any of the test vehicles yet, so heavy acceleration will cause the vehicle to pull depending upon which wheel gets more traction. That said, because the motors are per-wheel and not per-axle (no axles…) then this should be very easily software mitigated. This also isn’t “tracking” per-se, it’s torque steer. Tracking is straight line, constant speed and generally is controlled by wheel toe angles and (mis)alignment. The biggest concern would be torque steering while under high lateral loads (heavy acceleration out of a corner) as the cg shifts around and puts more load on the outboard wheel (giving it more traction), so the software will need to have some sort of accelerometer input to compensate correctly, but these are cheap and most electronic devices have them now.

[john-malcom]

I have not observed such behavior in any of the videos I have seen. Where did you see that? If in the moose test video that was driver input to negotiate the course. Electronic stability control and torque factoring prevents that from happening on its own

[macgreiner]

Has there been any discussion regarding the amount of rudder effect the two front wheel pods will have at speed? I wonder how this impacts steering stability at speed?

[len]

I have only heard the “ vehicle” is rated for ~ 100 mph / 110 mph rpm limited. I suppose confirmed as they move to production intent

[vernon-sinnott]

[macgreiner]

Thanks – not sure I caught anything in there describing whether ruddering will be an issue.

[jeffrey-parker]

I don’t think I understand your concern…

If you think a straight board-like member will try to keep the vehicle going in the direction that they are pointed. Yes, that is what “rudders” do.

If the rudder is straight and stationary (stabilizer) and the vehicle tries to turn, there would be a resistance (drag) to the turn as fluid (air) would be stopped by the stabilizer. But if the rudder is able to move, then as the rudder turns then the fluid is redirected and the resistance is reduced, and the turn is “assisted”.

The air strake or stabilizer pictured on the LMP2 car tries to keep the car going straight with less drag in the high-speed straights and adds drag/downforce while going around corners.

Now if that air strake was moveable, it would A) be called a rudder, and B) directly affect the yaw and assist in changing the horizontal direction in which the nose is pointing.

In my opinion the Aptera has both, rudders (wheel pants) and a stabilizer (rear wheel aero cover). So gets the best of both? And even if there is a great gust of wind directly perpendicular to the wheel pants and the rear wheel, the Aptera is aerodynamically designed to slip through the air in all directions. You’d probably feel less of an effect than a big boxy car.

[christopher-barrett]

I wonder what the effect you speak of is. I believe that the “torque vector system” is better than traction control, and the aerodynamic nature of the shell of the vehicle makes it likely to be extremely stable, similar to a track car. Maybe, due to light nature, above 110MPH it might be a problem, but I doubt that too. Just a limit on the motor so it will last, and not overheat.

[kerbe2705]

@Simon Meyer At one point we discussed if Aptera was planning to use “differential steering” (the front-wheel version of torque vectoring) at speed, switching to adjusting wheel speed to effect course corrections rather than turning the front wheel pants, causing them to act like rudders.

Unless it’s an emergency maneuver, most steering at speed is rather gentle and incremental so the wheel pants won’t be turned radically into the onrushing air stream.