TuSimple to Test Completely Self-Driving Trucks in New Driver-Out Pilot Program

By TuSimple's editorial team
Jul 21


To date, no one has taken a human driver entirely out of the cab of a semi-truck to deliver freight on public roads. In the coming months, we intend to change that.

The TuSimple Driver-Out pilot program is intended to validate our Navistar purpose-built Level 4 (L4) class 8 semi-truck technology. The goal for this driverless trucking pilot is to publicly demonstrate the safety, maturity, and functionality of our autonomous driving system, and validate that our autonomous driving system is ready for commercial production. This is done by completely removing the requirement for a human to operate the vehicle.

The Importance of Testing Driver-Out Autonomous Technology

Before this pilot, a human has always been the last line of defense from abnormal risks in a vehicle. Driver-Out takes responsibility away from the human driver and places it solely on our autonomous driving system. Removing a human driver from the vehicle is a tremendously complicated process that involves our proprietary software, integration of hardware from multiple strategic partners, and numerous layers of safety verification. We are building a safe and reliable system with double and sometimes triple redundancy that is intended to ensure the driverless trucking system is capable of identifying situations ahead of time, evaluating these situations, and safely resolving these situations entirely on its own.

It is important to note that there is a significant difference between the technical and operating complexity of a driver-in system (L2/L3) and our driver-out system (L4). L2/L3 systems are expected to make mistakes, even safety-critical ones. As such, they all maintain a backup human driver with full responsibility for the vehicle and the expectation that the human driver must intervene when needed. With an L4 truck, any internal hardware or software failure and all on-road scenarios must be detected and mitigated independently by the truck’s systems. Most autonomous driving systems for trucks are designed to operate in L2 and L3 in which the human bears the ultimate responsibility. The ultimate goal of developing L4 autonomous semi-truck technology is to be able to completely remove the human driver by equipping the autonomous driving system with the ability to completely replicate these types of human decisions and actions.


Driver Required
level 0

Zero autonomy; the driver performs all driving tasks.

level 1

Vehicle is controlled by the driver, but some driving assist features may be included in the vehicle design.

level 2

Vehicle has combined automated functions, like acceleration and steering, but the driver must remain engaged with the driving task and monitor the environment at all times.

level 3

Driver is a necessity, but is not required to monitor the environment. The driver must be ready to take control of the vehicle at all times with notice.

Full Driver-Out
level 4

The vehicle is capable of performing all driving functions under certain conditions. The driver may have the option to control the vehicle.

level 5

The vehicle is capable of performing all driving functions under all conditions. The driver may have the option to control the vehicle.

We believe that our proprietary autonomous driving system uniquely positions us to be the first autonomous driving company to have an L4 semi-truck perform multiple runs on public roads with a fully-loaded trailer without a human in the cab.

What is TuSimple’s Driver-Out Pilot Program?

During our Driver-Out pilot, our truck will operate autonomously from the point of origin to the end destination on a commercial shipping route between Phoenix and Tucson. The pilot will consist of multiple functional trips over several days while hauling real freight. The selected route includes scenarios experienced in most typical freight operations; terminals, surface streets, and highways that travel through city centers and suburban areas. We are also solving for more complex scenarios, such as lane closures due to accidents, real-time construction-related changes, and unknown objects on the road.

In these autonomous test runs, success will not be measured solely on delivering freight to the final destination. It will also be measured by the consistency with which our autonomous driving system navigates its way to a Minimal Risk Condition (MRC) if our system senses degradation or operates outside its Operational Design Domain (ODD). As such, the truck does not need to be able to handle every possible driving scenario, but it must be able to safely enter MRC when an unknown scenario is detected. Entering MRC successfully when system conditions change through hardware or software degradation or operation outside of its ODD will be a factor in validating the readiness of our hardware approach and our software solution.

How We Prepare for Driverless Trucking

To prepare for fully driverless trucking, we designed our autonomous system from the ground up, taking a rigorous engineering approach to analyze the functions and potential failures for each component. Goals that we have achieved towards our Driver-Out milestone include the following:

  • Removed single point of failure and—for some critical components—added double and triple redundancies
  • Designed many electrical components to support self-diagnostics and resistance to any hardware failure
  • Collaborated with our Tier-1 partners to design the first and only fully redundant, L4-capable steering and braking system for heavy trucks
  • Upgraded our truck sensor suites with a variety of integrated sensors, including an in-house designed camera system that enables night operations, a long-range LiDAR, mid-range LiDARs, radars, and an ultrasonic system
  • Designed an automatic data pipeline that employs AI algorithms to analyze and discover rare events by using the millions of miles of road data we collect, which provides a more extensive representation of potential road incidents
  • Implemented a continuous improvement process to address each new event we find on the road: capture requirements, generate system design, implement solutions, and thorough tests of updated design

Upgraded Sensor Suites

Upgraded Sensor Suits

Sensor suite location prototype

location prototype

The question for our Driver-Out program advancement is not if, but when. We are laser-focused on ensuring safety because the TuSimple team is truly designing a first-of-its-kind solution to successfully complete Driver-Out. We are currently in the third phase of a four-step process required to run a successful pilot test:

Phase 1 focused on designing the autonomous system architecture.
Phase 2 involved developing our first equipment prototype in partnership with Navistar.
Phase 3 involves completing the equipping of trucks that we use for testing, a comprehensive safety case including core areas of system engineering, functional safety, and internal process audits, as well as system validation and verification of redundancy, MRC, and our TuConnect truck monitoring system.
Phase 4 requires that we perform the final validation of our complete L4-designed solution, which we expect to complete later this year.

Requirement Definition

Product | FuSa Requirement HW & SW | Architecture & System Design

Platform Readiness

Exposure Analysis | HW & SW Integration | Component | Test Bench Verification

System Verification

Criteria Acceptance, Autonomy Release, System Verification, Optimization | Design Finalization

System Validation

Driver-Out Road Valiadtion

Q1′ 2020
Q4′ 2021

We will not begin Driver-Out autonomous testing until we have complete confidence that we have achieved our rigorous safety standards and requirements. We know that Driver-Out will be challenging, but our extensive experience over the last six years gives us confidence that we are ready for this groundbreaking program.

Posted by TuSimple

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