Quote:
Originally Posted by geraldjust
Seems like the torque sensor is a active type. That on the ring their active circuitry that then puts out to voltages that correspond to the torque. so im thinking some sort of voltage divider but then its a fixed rate and doesnt taper off. You would also lose more "help" that the rack gives.
Second option would be a op-amp and a external chip controlling the curve. i think that more "programmable" but would be more complicated.
Third, maybe some zener diodes to always max out right before the limit. Simple, wont cut the PS, and it will leave it the feeling of its operating range the same.
I dont think the angle data or speed would be needed. if people are calming that this still happens at speeds out at the track i think.
|
Thanks for those pics. This makes things clearer. Im pretty sure the two rings are not the actual sensor but a rotary union/lead through. I would assume that there is a strain gauge sensor on side of the shaft, which is supplied with the measuring signals/voltage by those two rings.
Nevertheless, the actually important point is, that there is a cable with connector between the sensor and the ECU unit. So it should be absolutely feasible to put an additional unit in between which limits the output voltage and in this way avoids the cut off. Using the correct connectors and pins, this could be a Plug&Play solution.
Angle data would only be needed to still keep the "lock overload protection". Means, If more then eg 90% of max steering angle is achieved, the system behaves as normal/factory. All the add-in unit needs to do is to just hand through the actual signal of the torque sensor without touching it if this angle over 90% condition is met. If the angle is below that (condition is not met), the max torque sensor output is simply limited to the equal of 5.9Nm by that hypothetical add-in box.
This would keep the behavior of the system in Standard driving conditions Like factory. Under Racing conditions, where the problematic higher loads are supplied to the steering rack, the maximum available support is limited to the value which is anyway the maximum allowed by the factory electronics. Only difference is that the cut off is avoided by never exceeding the 5.9 respectively 6Nm.
It could be kind of a "voltage limiter", which allows only voltages below {voltage equal to 5.9Nm} to pass. Everything above that value would be limited to {voltage equal to 5.9Nm}. This unit is pretty much always on and only bypassed (means actual torque sensor voltage is delivered to EPS ECU) if steering angle is above 90% of maximum.
As said, Im no expert in electronics and programming. Im the mechanical guy. But I would guess that such a box/logic should not be that big deal.
CAN hi/lo should be anyway present at the main connector of the EPS ECU and a power supply for the add-in unit is anyway needed, what I guess can also be found in this connector. So there would be two points where the add-in unit is connected inline the factory harness. Once at the main connector for power and can, and once between the torque sensor and the EPS ECU unit.