Software-Defined Throttle-by-Wire System for an Autonomous-Ready E-Buggy Platform

The program was initiated to demonstrate that a software-centric throttle architecture could meet the precision, safety, and scalability demands of autonomous-ready vehicle platforms, without the mechanical complexity that limits conventional designs.

Key objectives included:

• Develop a software-defined throttle architecture minimizing mechanical dependencies
• Enable precise, closed-loop torque control with high-resolution sensor feedback
• Support dual-mode operation for seamless manual and autonomous control
• Achieve ASIL D-ready functional safety with no single points of failure
• Enable SDV alignment and Level 3+ autonomous readiness
• Reduce cost and accelerate time-to-market through modular, reusable design

We designed and implemented a software-defined Throttle-by-Wire system that replaces mechanical throttle linkages with a fully electronic, software-controlled architecture. The system supports both manual driver input and autonomous control commands within a single unified platform, enabling seamless transition between driving modes without hardware changes.

The control architecture is built for real-time precision, functional safety, and SDV readiness, with a modular software design that supports OTA-based feature upgrades and future capability expansion without hardware redesign.

Key Highlights

RTOS-Driven Real-Time Throttle Control

• We implemented an RTOS-based architecture on the NXP S32K Series microcontroller, isolating critical throttle signal processing and torque control tasks from non-critical functions. This ensures deterministic execution timing and stable throttle response under high computational load, a prerequisite for safe autonomous operation.

High-Precision Closed-Loop Feedback System

• We designed a closed-loop control strategy using high-resolution Hall-effect sensors to continuously monitor wheel speed and drivetrain response. Sensor readings are compared against target torque demands in real time, enabling immediate correction of deviations and eliminating lag and drift from throttle execution.

PID-Based Torque Control Algorithm

• We implemented a PID control algorithm that continuously computes the error between the target and actual speeds and dynamically adjusts the throttle output accordingly. This delivers smooth acceleration, precise torque control, and oscillation-free performance across the full operating range.

CAN-Based ECU Communication

• We used CAN as the primary communication layer between throttle control units, sensors, and ADAS modules. This replaces complex point-to-point wiring with a reliable serial bus, enabling synchronized real-time data exchange across the full control network.

Dual-Mode Throttle-by-Wire Operation

• We implemented dual-mode operation that processes both driver pedal input and digital throttle commands from ADAS or autonomous controllers. The system determines the active control source at runtime and executes the appropriate torque demand, enabling safe handoff between manual and autonomous driving modes.

ASIL D-Ready Safety Architecture

• We designed a safety framework with redundant sensing, signal validation, and independent control paths to eliminate single points of failure. The architecture meets ASIL D readiness requirements and ensures safe, predictable throttle behaviour across normal operation, fault conditions, and edge cases.

SDV-Ready and Cost-Optimized Design

• We delivered a modular, software-defined throttle platform with a clean separation between hardware interfaces and application logic. This structure supports OTA-based feature upgrades and future capability additions without hardware changes, while reducing integration complexity across development, manufacturing, and validation.

• Delivered precise, software-controlled torque response, resulting in smoother acceleration and improved vehicle stability during real-time operation
• Reduced energy consumption through intelligent torque mapping and demand-based actuation, leading to improved drivetrain efficiency
• Enabled a production-ready Throttle-by-Wire platform, successfully supporting seamless integration with Level 3+ autonomous systems
• Lowered system complexity and cost by eliminating mechanical dependencies and simplifying architecture
• Accelerated development cycles by reducing integration effort and validation timelines through reusable software components
• Established an SDV-ready platform capable of continuous feature evolution through OTA updates without hardware redesign