Tesla Inc (TSLA)

[boston745]

Researcher Discovers Tesla Design Flaw That May Cause Unintended Acceleration; NHTSA Reopens Investigation

The National Highway Traffic Safety Administration (NHTSA) has reopened its investigation into a potential design flaw in Tesla vehicles, which may lead to sudden unintended acceleration. This comes after allegations were made that a voltage spike deep within the control systems could cause the vehicle to incorrectly read an accelerator input, even when none has occurred.

When Voltage Spikes Trigger Unintended Acceleration
Under certain circumstances, such as slow driving, when the power steering requires more power, the draw on the 12-volt battery can cause a significant spike in the system. This voltage surge could lead the inverter to incorrectly conclude that the accelerator pedal has been pressed, resulting in unintended acceleration.

This unexpected acceleration could theoretically happen when a voltage spike, lasting only microseconds, occurs simultaneously as the car performs an ADC check, also lasting microseconds. Belt suggests that the frequency of these events aligns with the 200 or so incidents reported between 2013 and 2019.

Adding complexity to this issue, Belt contends that due to the nature of the fault, it does not get logged as an error. The inverter’s misinterpretation of a voltage spike as a throttle input leaves no trace, leading to discrepancies between Tesla's vehicle data and owners' accounts, possibly explaining why the ODI initially denied the petition.

While Belt's allegations primarily focus on the Model 3, which features a unique inverter design, he notes that similar errors could occur in Model S and Model X vehicles. This opens up the potential for a broader scope in the ongoing investigation.

NHTSA Petition Claims Tesla Sudden Unintended Acceleration Is Real

What's worse is that the incorrectly increased sensor signals will be sent via the CAN bus to the vehicle logs, causing Tesla and NHTSA to conclude that the driver caused the sudden increase in torque by stepping on the accelerator pedal. But in this case, the sudden acceleration was caused not by the driver stepping on the accelerator pedal but by a random superposition of a negative-going voltage spike (which is about 100 microseconds long), and the sampling time of the analog-to-digital converter (which is about 10 microseconds long). This random superposition explains the low occurrence rate of sudden acceleration in Tesla vehicles

SUA has impacted every main Tesla car model S/X, 3/Y, & even the Cybertruck. Im not aware of an incident involving a Semi...yet...although the one that drove into the trees with an engine fire may have experienced SUA.
As this issue has impacted just about every Tesla model and year, i doubt Dr Belt's theory in relation to the the origin of the fault, is exactly correct and certainly not easy to fix as its still a problem. Thus i expect the NHTSA will deny this petition at some point despite this issue continuing to plague Teslas. I believe the problem of SUA is EM interference induced which impacts other EVs as well per a study in China. EMI can cause these voltage spikes to compensate from a drop in voltage as described in the following quote. E3 usually pertains to EM blast from a nuclear explosion but during geostorms/unrest this same sort of voltage depression can be observed in electrical systems.

E3 can also affect subtransmission and distribution systems by causing harmonic distortion and voltage depression. The voltage regulators at the substation will attempt to correct for low voltage levels on distribution circuits. This attempt can result in overvoltages when the E3 stimulus decays to a low value

Part 2 - Proof Electromagnetic radiation is causing EVs to go out of control and spontaneously combust.

4). Among the data records during the accidents according to the background data of the crashed vehicles or the data of on-vehicle terminals, the position values of most accelerator pedals were very high(99%) while the values of brake pedals were 0% or only non-zero in very limited moments (see Fig. 1 and Fig. 2).

Continued very high accelerator pressure with no braking is how you differentiate SUA from pedal misapplication.

In  recent  years,  there  have  been  numerous  out-of-control  accidents  of  electric  vehicles.

Occasional fault of electronic control unit caused by  electromagnetic interference

External  electromagnetic  interference  refers  to  that  caused  by electromagnetic  radiation  of  various  electrical  facilities  including  the  high  voltage  transmission  line, broadcasting  TV  devices  and  radio  communication  equipment  as  well  as  natural  phenomena  such  as lightning.

Electromagnetic  wave  interferes  the  electric  control  system  of  automobile  through  wiring  harness and  car  body to  make  it  hard  to  perform  or  even  send  wrong  instructions leading  to  wrong  actions  of various  actuators,  affecting  the  safety,  reliability  and  stability  of  automobile  driving.  The electromagnetic  interference  affects  the  automobile  electronic  control  system  mainly  in  two  ways:  one is  to  affect  the  input  signal  of  the  sensor  of  the  electronic  control  system,  causing  distortion  and resulting  in  electric  control  signal  where  the  ECU  output  does  not  match  the  driver's  intention,  which leads  to  the  wrong  operation  of  the  actuator;  the  other  is  to  interfere  the  ECU  output  signal  to  result  in its deviation,  misleading the operation of  the actuator.

The most common cause of Natural EMI includes:

Lightning

Solar Magnetic Storms

Earth’s Magnetic Field Flux

Cosmic Radiation

Quote Sources:
https://www.notateslaapp.com/news/1515/investigation-into-unintended-acceleration-of-teslas-reopened-could-a-design-flaw-be-at-fault
https://www.autoevolution.com/news/breaking-nhtsa-petition-shows-tesla-s-sudden-unintended-acceleration-is-real-and-curable-217525.html
https://www.researchgate.net/publication/346368508_Special_Investigation_and_Countermeasure_Suggestions_on_Electric_Vehicle_out-of-control_Accidents