Incident: Electric Motorcycle Software Glitch Causes Power Loss and Recall

Published Date: 2014-01-17

Postmortem Analysis
Timeline 1. The software failure incident with Zero's electric motorcycles happened in 2012 and 2013 as per the article [23828]. Therefore, the timeline of the software failure incident can be estimated as follows: Step 1: The article was published on 2014-01-17. Step 2: The incident with the electric motorcycles occurred in 2012 and 2013. Step 3: Based on the above information, the software failure incident likely occurred between 2012 and 2013.
System 1. Zero's bikes controller software [23828] 2. Motor encoder and controller communication system [23828]
Responsible Organization 1. Zero Motorcycles - Zero Motorcycles was responsible for causing the software failure incident by releasing bikes with a problem in the controller software, leading to the recall of all 2012 and 2013 models [23828].
Impacted Organization 1. Zero Motorcycles [23828] 2. National Highway Traffic Safety Administration [23828]
Software Causes 1. The failure incident was caused by a problem with the controller software in Zero's electric motorcycles, leading to a loss of power while riding [23828]. 2. The glitch in the software was related to a failure of communication between the motor encoder and the controller, resulting in the motor shutting down unexpectedly [23828]. 3. The software issue was widespread and affected multiple 2012 and 2013 Zero models, leading to a recall of all 667 motorcycles built in those years [23828].
Non-software Causes 1. The failure incident was caused by a glitch related to the motor encoder failing to communicate properly with the controller, resulting in the motor shutting down unexpectedly [23828]. 2. The issue was also attributed to random, infrequent, and unrelated signal faults that could not be avoided in the lifetime of the motorcycle, as identified by Zero Motorcycles and Sevcon [23828]. 3. Previous recalls by Zero in 2012 for similar issues, such as sticking throttles and front brake bracket problems, indicate a history of mechanical issues beyond just software glitches [23828].
Impacts 1. The software failure incident led to a loss of power while riding the electric motorcycle, causing the rider to come to a stop on the side of the freeway, posing a safety risk [23828]. 2. The incident resulted in a recall of all 2012 and 2013 Zero model motorcycles due to the controller software problem, affecting a total of 667 motorcycles [23828]. 3. The failure to communicate between the motor encoder and the controller caused the motor to shut down randomly, leading to potential breakdowns and inconvenience for the riders [23828]. 4. The software glitch impacted the reputation of Zero Motorcycles, as it was not the first time such issues had occurred, with previous recalls for similar problems in 2012 [23828].
Preventions 1. Regular and thorough testing of the controller software before releasing the electric motorcycles to the market could have potentially prevented the software failure incident [23828]. 2. Implementing a more robust communication protocol between the motor encoder and the controller to ensure accurate and reliable data transmission could have helped prevent the glitch that led to the motor shutdown [23828]. 3. Conducting more extensive quality assurance processes during the development phase to catch and address any potential software bugs or faults before the motorcycles are sold to customers could have mitigated the issue [23828].
Fixes 1. Upgrading the firmware on all affected motorcycles [23828] 2. Sending the logs into Zero for analysis and repair [23828] 3. Bringing the motorcycle to the nearest dealer for a firmware/software flash update [23828]
References 1. Electric motorcycle community 2. Zero Motorcycles 3. National Highway Traffic Safety Administration 4. Sevcon 5. Zero's director of powertrain engineering 6. Zero's director of customer experience 7. Zero's letter to the National Highway Traffic Safety Administration 8. Zero's owners 9. Zero's nearest dealer

Software Taxonomy of Faults

Category Option Rationale
Recurring one_organization, multiple_organization (a) The software failure incident related to Zero Motorcycles' products has happened again within the same organization. The article mentions that Zero Motorcycles had a similar issue in the past, where they had to recall 315 bikes for a similar problem in 2012. This indicates a recurring software failure incident within the organization [23828]. (b) The software failure incident related to similar issues has also occurred at other organizations. The article mentions that Zero Motorcycles is not the only company facing such software glitches. It states that modern cars and bikes are more like rolling computers, and repairs often involve updating software. This suggests that similar incidents may have occurred in the automotive industry or other industries where software plays a crucial role [23828].
Phase (Design/Operation) design, operation (a) The software failure incident in the article is related to the design phase. The issue stemmed from a problem with the controller software in Zero's electric motorcycles. The glitch was identified as a failure to communicate between the motor encoder and the controller, leading to the motor shutting down unexpectedly [23828]. (b) The software failure incident is also related to the operation phase. The failure occurred while the motorcycle was in operation, causing the rider to lose power and experience issues while riding on the highway. The software glitch affected the functionality of the electric motorcycle during its operation, leading to safety concerns for the rider [23828].
Boundary (Internal/External) within_system (a) The software failure incident described in the article is within_system. The failure was attributed to a problem with the controller software of Zero's electric motorcycles. The issue was related to a glitch in communication between the motor encoder and the controller, causing the motor to shut down unexpectedly [23828]. The company had to work with its motor partners to fix the problem and issued a recall to upgrade the firmware on all affected motorcycles [23828].
Nature (Human/Non-human) non-human_actions, human_actions (a) The software failure incident in the article was primarily due to non-human actions. The issue stemmed from a glitch in the communication between the motor encoder and the controller of the electric motorcycles manufactured by Zero. This glitch caused the motor to shut down unexpectedly, leading to power loss while riding [23828]. (b) Human actions were involved in addressing the software failure incident. Zero, the company behind the electric motorcycles, worked extensively with their motor partners at Sevcon to find a fix for the glitch. Engineers and technicians from both companies collaborated to upgrade the firmware on the affected motorcycles to resolve the issue. Additionally, Zero made efforts to make the firmware upgrade process easy for the owners by providing instructions on how to send logs and get the necessary updates done at the nearest dealer [23828].
Dimension (Hardware/Software) hardware, software (a) The software failure incident described in the article was primarily due to hardware-related issues. The failure was attributed to a problem with the controller software in Zero's electric motorcycles, specifically related to the motor encoder not communicating effectively with the controller due to signal faults originating in the hardware components [23828]. The issue led to the motor shutting down unexpectedly, causing the motorcycle to lose power while in operation. (b) The software failure incident was also related to software issues. The glitch in the controller software, which caused the motor to shut down due to communication failures with the motor encoder, was a key software-related problem identified in the article [23828]. This software issue led to the recall of 2012 and 2013 Zero models to upgrade the firmware and address the underlying software fault.
Objective (Malicious/Non-malicious) non-malicious (a) The software failure incident described in the article is non-malicious. The failure was attributed to a problem with the controller software in Zero Motorcycles, specifically related to a glitch in communication between the motor encoder and the controller. This glitch caused the motor to shut down unexpectedly, leading to issues for the motorcycle riders [23828]. The company, Zero Motorcycles, acknowledged the issue and took steps to address it by issuing a recall for affected models and working on a firmware upgrade to fix the problem [23828]. (b) The software failure incident was not caused by malicious intent but rather by a technical issue in the software that affected the functionality of the electric motorcycles. The failure was not a result of deliberate actions to harm the system but rather a consequence of a software bug that impacted the communication between components in the motorcycle's electric motor system [23828].
Intent (Poor/Accidental Decisions) accidental_decisions (a) The software failure incident described in the article was not primarily due to poor decisions but rather a technical issue related to the controller software of Zero's electric motorcycles. The failure was attributed to a glitch in the communication between the motor encoder and the controller, leading to the motor shutting down unexpectedly [23828]. The company had been working on the firmware for several months before realizing the widespread nature of the issue, indicating that it was more of a technical challenge than a result of poor decisions. (b) The software failure incident can be categorized more as an accidental decision or unintended consequence rather than a failure due to poor decisions. The issue with the controller software causing the motor to shut down unexpectedly was not a deliberate choice but rather a technical flaw that needed to be addressed through firmware upgrades [23828]. The incident was described as a glitch in communication between components rather than a result of intentional poor decisions made by the company.
Capability (Incompetence/Accidental) accidental (a) The software failure incident in the article was not due to development incompetence. The issue with the Zero motorcycles was identified as a glitch in the communication between the motor encoder and the controller, leading to the motor shutting down unexpectedly. The problem was traced back to a failure to communicate effectively between these components, rather than a lack of professional competence in the development process [23828]. (b) The software failure incident in the article was accidental. The glitch that caused the motor to shut down unexpectedly was described as a failure to communicate between the motor encoder and the controller. This issue was not intentional but rather an accidental flaw in the system that led to the recall of the affected motorcycles [23828].
Duration temporary The software failure incident described in the article was temporary. The issue was related to a glitch in the controller software of Zero's electric motorcycles, specifically affecting the communication between the motor encoder and the controller. This glitch caused the motor to shut down unexpectedly, leading to temporary loss of power for the rider [23828]. The company, Zero, acknowledged the problem and issued a recall for affected models to upgrade the firmware, indicating that the failure was not permanent but rather a result of specific circumstances related to the software glitch.
Behaviour crash, omission, value, other (a) crash: The software failure incident described in the article can be categorized as a crash. The incident involved the electric motorcycle losing power while in operation, leading to a complete shutdown of the motor and causing the rider to be stranded on the side of the freeway [23828]. (b) omission: The software failure incident can also be categorized as an omission. The failure of the controller software to properly communicate with the motor encoder resulted in the system omitting to perform its intended function of accurately determining the position of the magnetic rotor inside the electric motor, leading to the motor shutting down unexpectedly [23828]. (c) timing: The software failure incident does not align with a timing failure as the system was not described as performing its intended functions too late or too early in the article [23828]. (d) value: The software failure incident can be categorized as a value failure. The system performed its intended functions incorrectly due to the failure of the motor encoder to communicate effectively with the controller, leading to the motor shutting down and causing the motorcycle to lose power unexpectedly [23828]. (e) byzantine: The software failure incident does not align with a byzantine failure as there were no mentions of inconsistent responses or interactions in the system behavior described in the article [23828]. (f) other: The other behavior exhibited by the software failure incident is a recurring issue despite previous recalls and attempts to fix similar problems in the past. The article mentions that Zero Motorcycles had faced similar issues before, including recalls for sticking throttles and front brake bracket problems, indicating a pattern of software-related failures in their products [23828].

IoT System Layer

Layer Option Rationale
Perception embedded_software The software failure incident described in the article is related to the embedded software layer of the cyber physical system. The issue was specifically related to a problem with the controller software in Zero's electric motorcycles. The failure was caused by a glitch in the communication between the motor encoder and the controller, leading to the motor shutting down unexpectedly, as described by Zero's director of powertrain engineering, Ryan Biffard [23828]. The firmware upgrade issued by Zero to address this issue indicates that the root cause of the failure was within the embedded software of the motorcycles.
Communication link_level The software failure incident described in the article was related to the communication layer of the cyber physical system that failed at the link_level. The failure was due to a glitch in the communication between the motor encoder and the controller, which led to the motor shutting down unexpectedly, causing the motorcycle to lose power [23828]. The issue was specifically related to the motor encoder sending signals back to the controller to indicate the position of the magnetic rotor inside the electric motor. If the encoder detected any anomalies, it would shut down the motor, resulting in the motorcycle losing power while in operation. This failure at the link_level highlights a critical communication breakdown within the system that impacted the overall functionality of the electric motorcycle.
Application TRUE The software failure incident described in the article was related to the application layer of the cyber physical system. The failure was attributed to a problem with the controller software of Zero's electric motorcycles, specifically with the firmware controlling the motor encoder's communication with the controller. This issue led to the motor shutting down unexpectedly, causing the motorcycle to lose power while in operation [23828].

Other Details

Category Option Rationale
Consequence property, delay, non-human, theoretical_consequence (a) death: The software failure incident did not result in any deaths as per the articles [23828]. (b) harm: There is no mention of people being physically harmed due to the software failure incident [23828]. (c) basic: The software failure incident did not impact people's access to food or shelter [23828]. (d) property: People's material goods, money, or data were impacted due to the software failure incident as Zero Motorcycles had to issue a recall for every 2012 and 2013 model due to a problem with its controller software [23828]. (e) delay: People had to postpone activities due to the software failure incident, as the individual in the article had to stop his commute, turn around, and head home due to the issue with the electric motorcycle [23828]. (f) non-human: Non-human entities were impacted due to the software failure incident, specifically the electric motorcycles manufactured by Zero Motorcycles [23828]. (g) no_consequence: There were observed consequences of the software failure incident, such as the need for a recall and the inconvenience caused to the motorcycle owners [23828]. (h) theoretical_consequence: There were potential consequences discussed regarding the software failure incident, such as the possibility of wireless updates being pushed to vehicles in the future to address issues promptly [23828]. (i) other: There were no other consequences mentioned in the articles [23828].
Domain transportation (a) The failed system in the incident was related to the transportation industry, specifically electric motorcycles. The software failure incident affected Zero Motorcycles, leading to a recall of all 2012 and 2013 models due to a problem with the controller software [23828]. The issue stemmed from a failure in communication between the motor encoder and the controller, causing the motor to shut down unexpectedly, as described by Zero's director of powertrain engineering, Ryan Biffard [23828]. The firmware upgrade to address the glitch was necessary to ensure the proper functioning of the electric motorcycles and prevent potential safety hazards on the road [23828].

Sources

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