Rock and Roll with NASA Challenge

The next era of lunar exploration demands a new kind of wheel - one that can sprint across razor-sharp regolith, shrug off extremely cold nights, and keep a rover rolling day after lunar day. The Rock and Roll with NASA Challenge seeks that breakthrough. If you can imagine a lightweight, compliant wheel that stays tough at higher speeds while carrying lots of  cargo, your ideas could set the pace for surface missions to follow.

For this phased Challenge, Phase 1 rewards the best concepts and analyses, Phase 2 funds prototypes, and Phase 3 puts the best wheels through a live obstacle course simulating the lunar terrain. Along the way, you’ll receive feedback from NASA mobility engineers and the chance to see your hardware pushed to its limits.  In Phase 3, to prove concepts, NASA is using MicroChariot, a nimble, 45 kg test rover that will test the best designs from Phase 1 & Phase 2 at the Johnson Space Center Rockyard* in Houston, Texas.

Whether you’re a student team, a garage inventor, or a seasoned aerospace firm, this is your opportunity to rewrite the playbook of planetary mobility and leave tread marks on the future of exploration. Follow the challenge, assemble your crew, and roll out a solution that takes humanity back to the Moon.

*Please note that in the prelaunch stage of this challenge, a wheel diameter of 19-inches was stated. This has since been updated to 18-inch wheels, which is the official measurement for this challenge, going forward.

Photo Credit: Copyright Felix and Paul Studios

Design a compliant, lightweight wheel that attaches to MicroChariot, survives lunar extremes, and propels a rover at speeds up to 24 km/h over jagged terrain - all backed by your solid analysis and a build-ready plan. Deliver the idea, the CAD, and the evidence it works, and you are on the right path for NASA to give you the proving ground to show the world it can roll on the Moon.

Background

NASA is returning crews to the Moon to establish an enduring, science-driven presence that will serve as the springboard to Mars. The agency’s Moon-to-Mars Architecture lays out a phased campaign (see challenge Resources): the Human Lunar Return Segment  will test critical systems; the Foundational Exploration Segment scales up surface infrastructure; the Sustained Lunar Evolution Segment will use equipment currently being developed to create the lunar outpost, and; the Human to Mars Segment will extend operations into deep space and, ultimately, the Red Planet. In this framework, every new element - rockets, landers, habitats, spacesuits, mobility systems - must mesh like parts of a living ecosystem, each enabling the next stride outward.

Central to that ecosystem is mobility, and innovation in mobility will be key to maximizing exploration returns. The first wheels that carried astronauts on the lunar surface, in 1971, instantly tripled the exploration range and proved that a few kilograms of smart engineering could unlock kilometers of new science. Half a century later, the mobility and logistics scope has grown by orders of magnitude. Artemis cargo landers will drop equipment at sites in the polar highlands; scientific campaigns will demand daily sample runs into cratered darkness; crews will need quick lifts between power stations and habitats. All this motion is enabled through wheels. 

The challenge is a constant trade among traction, mass, materials, and durability. A new generation of wheel technology must be lightweight, compliant, robust, and scalable. These attributes underpin every ambitious surface scenario in the Moon-to-Mars roadmap.

On the Moon, the terrain is unforgiving. No roads - just sharp, electrostatically charged regolith ready to punish the unprepared. NASA’s rover engineers know that no vehicle is better than the tires it rides on. Sharp regolith abrades wheels, large temperature swings thermally stress components, and 1/6 gravity results in wheels having less traction. Rigid spoke wheels, like the ones qualified for Volatiles Investigating Polar Exploration Rover (VIPER), can crawl confidently at a slow pace, but at the higher speeds necessary to support human exploration, rigid spoke wheels are not optimal. A compliant, lightweight wheel is mission-enabling, reduces maintenance, and allows for faster pace operations - just as we have found here on Earth.

NASA and NASA partners are actively developing wheel technologies to meet the mobility demands of future lunar missions. Crowdsourcing will expand the community of solvers and invite fresh thinkers to surface “hidden-gem” technologies, materials, and compliance strategies  to fully explore the design space. Concepts will be down-selected, prototyped, mounted to the MicroChariot test rover, and tested at a NASA facility.

For solvers, the mandate is clear: re-imagine the wheel for the lunar environment, that moves faster and works longer than anything created to-date. Innovation counts, but so does manufacturability, mass efficiency, durability, and performance.

The Problem

Existing lunar rover wheels - engineered for low-speed, short-duration missions - cannot endure higher speeds, long lifetimes, and abrasive regolith of upcoming Artemis logistics operations.

As NASA prepares to ferry cargo between South-Pole landing zones and work sites kilometers away , it lacks a wheel that can survive the journey. The agency’s latest analysis of cargo mobility calls for traverses on slopes up to 20° and repeated runs at higher speeds to support the expected operational cadence. The Apollo LRV wheels, although successful, do not meet the current demands for sustained exploration. Higher speeds yield larger dynamic loads and increased probability of impacts with rocks and craters, due to poor visibility and shorter reaction times to avoid obstacles. Also, long service life results in repeated mechanical and thermal stresses. Therefore, non-rigid wheel technologies suitable for higher-speed, longer duration mobility are needed to meet the demands of future lunar missions.

The Lunar Environment

The Moon presents a landscape of  thermal extremes with surface temperatures that vary with latitude and solar illumination. The Equatorial region can reach +121 C (250 F), representing the warmest extreme. Conversely, permanently shadowed regions (PSRs) can experience extreme cold temperatures of as low as -255 C (-427 F).

Artemis will primarily focus on the lunar south polar region (~80 to 90 degrees latitude) due to the unique scientific and operational opportunities it provides. Unlike the equatorial region of the Moon, visited by Apollo, which follows a cycle of approximately 14 earth days of light followed by 14 Earth days of night, in the polar region the Sun appears to skim the horizon, circling the Moon's pole through a short range of altitudes. The combination of this low solar angle and the topography of the surface create sustainable exploration opportunities with locations ranging from nearly continuous sunlight throughout the year, for solar power generation, to areas that are permanently shadowed that sunlight never reaches which might yield rich natural resources. To maximize scientific and operations opportunities, mobility systems will need a wide temperature range capability.

The following table, 3.4.6.3-1 from the NASA DSNE Resource, shows that surface temperatures vary with latitude and solar illumination. The equator represents the warmest region, poles (85 deg lat) represent the coldest, and PSRs extreme cold.

Table 3.4.6.3-1 Lunar surface temperature extremes for various latitudes and solar illumination conditions from Williams et al. 2017. Mean temperatures are the plotted value with the max or min extremes taken from the error bars. Temperature for coldest permanently shadowed crater is from Paige and Siegler, 2016.

At the poles, illumination remains low-angle year-round, casting kilometer-long shadows that hide rocks, valleys, and craters until a rover’s tires touch them. Gravity, one-sixth of Earth’s, lets a vehicle haul heavier loads which magnifies inertia: once mass starts bouncing or sliding, it is harder to stop. The crater covered ground itself is no friendlier. Regolith dust is  jagged, sharp, and electrostatically clingy; laboratory tests show they abrade metals an order of magnitude faster than terrestrial basaltic sand, working their way into joints and shaving material away with every rotation. Add micrometeoroid pitting and high-energy solar and cosmic radiation, and a wheel must endure more than just rough ground; it must withstand a barrage of thermal cycling, vacuum-induced material outgassing, and radiation-driven embrittlement.

In short, the lunar worksite is a place where a poorly chosen wheel can fracture, fatigue, dig in, or grind itself away long before the rover’s mission is done. Any solution must therefore fuse compliance (to soften impacts and maintain contact), low mass (to conserve upmass and energy), and materials toughness (to outlast dust, cold, and time).

For a full range of environmental conditions see NASA's Cross-Program Design Specification for Natural Environments (DSNE).

Image 1: Example traverses showing landing locations and potential end-use locations. (NASA)

The Challenge: Structure and Goal

NASA is seeking novel rover wheel concepts that will enable advances in surface mobility and human space exploration. Of interest are flexible, lightweight wheel ideas that will reduce ground pressure, and absorb impacts during higher speed operations through rugged terrain. The selected wheel concepts will be prototyped and tested on the MicroChariot rover to demonstrate the technology and inform future flight wheel designs.

This is a three-phase, down-select challenge competition. The following provides an overview of each phase. The majority of detail is currently provided for Phase 1, as it is open to the public. More details about later stages, including their full submission requirements and judging criteria, will be released to the down-selected teams later in the challenge.

The MicroChariot Test-Bed

For this challenge, NASA has selected the MicroChariot rover as the common design and test platform, but the ultimate goal is a wheel architecture that can scale to larger lunar vehicles to form a suite of wheels that support a wide range of mobility systems. MicroChariot is a semi-autonomous logistics rover conceived for day-to-day chores around the Artemis South-Pole base – hauling instruments, laying cabling, or ferrying supplies from landers to labs. Key facts:

• Size & Mass (terrestrial): 1.02 m × 0.51 m × 0.18 m (40 in × 20 in × 7 in) chassis; ~45 kg (~442 N curb weight on Earth).
• Payload Capacity*: ~45 kg on Earth (~442 N on Earth) ⇒ ≈ 270 kg on Moon (~442 N under lunar gravity…6× mass advantage).
• Wheels**: 457 mm (18 in) diameter, 203 mm (8 in) wide, VIPER-style rigid spokes.
• Ground Clearance: nominal 165 mm (6.5 in) on the lunar version; the Ground-Test Unit can adjust ±76 mm (±3 in).
• Drive: fully electric, four independent wheel modules, current max speed 9.65 km/h (6 mph).

*In typical stop-start logistics duty, MicroChariot will hit dips, rocks, and have braking events that spike the wheel reaction force to as much as four times the nominal static load per wheel. Designs must therefore remain structurally sound and maintain traction under these transient peaks. All designs must meet the minimum load capacity baseline of 2 × gross vehicle lunar weight (= curb-weight + payload) distributed across the four wheels or the entire gross vehicle weight supported by only two wheels, as described in the Desired Attributes.

**In the prelaunch stage of this challenge, a wheel diameter of 19-inches was stated. This has since been updated to 18-inch wheels, which is the official measurement for this challenge, going forward.

The MicroChariot Rover and Your Design

• Fit: your design must bolt onto the MicroChariot wheel hub (see diagram below) so it can be installed without changes to the wheel hub.
• Function: while tuned for a 45 kg rover + 270 kg lunar payload (510 N gross rover weight or 115 lbf), your wheel should demonstrate pathways to larger diameters and loads; NASA cares about extensibility beyond MicroChariot.
• Proof: success in Phase 3’s live Rockyard demonstration will showcase a wheel technology capable of raising the benchmark on lunar surface mobility.

Image 2: MicroChariot Wheel Hub Mounting Interface

Challenge Structure

The overarching goal is to identify, prototype, and test innovative wheel solutions that explore new  designs, potentially incorporating characteristics such as lightweight, flexible, long service-life, and scalability to reduce mission risk and expand lunar exploration capabilities.

Phase 1 – Ideation (August - October 2025)
Goal: Create an innovative wheel and tire  design and show engineering rationale and analysis.
Deliverables:

• 3-D CAD model of the wheel assembly ( STEP).
• Whitepaper (≈ 7 pages) explaining your wheel design and how it addresses the Phase 1 desired attributes listed in the “How to Win?” section below.

Outcome: Panel of experts selects the most promising concepts (up to 10) for funding and designs move to Phase 2.

Phase 2 – Prototype (January - April 2026)
Goal: Fabricate two full-scale wheels that match the Phase 1 design.
Deliverables: 

• Wheel prototypes matching Phase 1 design (quantity 2 of same wheel)
• 3-D CAD model updates (STEP)
• Video of assembly and testing progress
• Summary of design changes, lessons learned, and potential future improvements
• Deliver one wheel prototype by deadline

Outcome: Panel of experts select up to 5 teams to advance to Phase 3. Selected teams are asked to ship or bring their solutions to Phase 3.

Phase 3 – Demonstration (target: summer 2026)
Goal: Demonstrate capabilities of Phase 2 fabricated wheels on MicroChariot Rover at NASA’s Johnson Space Center Rockyard in Houston, Texas.

Deliverables: 

• Team participation at NASA Johnson Space Center Rockyard
• Presentation on wheel design in conference room setting
• Deliver two wheel prototypes before Phase 3

Outcome: Panel of experts selects the most capable wheel.  Additionally, all wheel designs showing promise will be shared within the NASA community for possible additional testing and use in future missions.

Prizes

*The distribution of Phase 1 categorical prizes across the two categories will be determined during judging. Phase 1 finalists are eligible to win categorical prizes in addition to finalist prizes. Those that win only categorical prizes will not participate in Phase 2.

**All Phase 2 participants will ship at least one wheel prototype to NASA. Winners will ship or bring their wheels to Phase 3.

***Prize funds can be used at the discretion of the winners and can be used for travel and shipping of solutions; shipping and travel costs are at the expense of the winners.

Timeline

How to Win?

To be eligible for an award, your proposal must, at minimum:

• Satisfy the Judging Criteria requirements.
• Thoughtfully address the Submission Form questions.
• Be scored higher than your competitors!

Ready to answer the challenge? Below are the key pieces you need to submit to Phase 1.

Phase 1 Technical Requirements & Performance Targets:

The following requirements must be met to be considered for a Phase 1 Finalist prize:

Must-Have Requirements

1. Compliant design: wheel structure must flex to absorb obstacle impacts and reduce peak loads, while operating at speeds up to 24 km/h (15 mph) on lunar-simulant terrain.
2. Hub integration: no part of the concept may intrude into a central keep-out (see hub diagram (Image 2) for measurements); attachment to the outer hub surface is allowed.
3. Phase 1 package: submit a STEP 3-D CAD model and approximately 7-page whitepaper detailing innovation, compliance mechanism, expected performance, materials, construction method, mass estimate, and preliminary analysis or test data.

Phase 1 Desired Attributes (Scored Advantage)

The following elements are desired, in addition to the must-have requirements:

1. Low mass: target less than 2.3 kg (5 lb) per wheel while maintaining strength.
2. High strength-to-weight ratio: use analysis and material data to justify claims.
3. Geometry: outer diameter 483 mm (18 in) and width 203 mm (8 in). Please note that strict geometry is not a hard requirement for Phase 1 submissions. However, being able to adapt your design to meet the geometry requirement in Phase 2 will be required. Therefore, if your Phase 1 design does not already meet these requirements, you should demonstrate in your plan how you intend to adapt the design in Phase 2.
4. Innovative: clearly distinct from publicly documented compliant tire technology, including but not limited to the Apollo LRV wire-mesh tires and the Spring Tires.
5. Dust tolerance: self-clearing tread or geometry that limits regolith intrusion.
6. Lunar environment compatibility: materials and construction must function over a large temperature range, in vacuum, abrasive dust, and on uneven terrain.  Please note wheel designs able to withstand the broadest range inclusive of Moon polar region (~80-90 degrees latitude) temperatures will be given preferential ranking and those including the extremes of PSRs will be ranked even higher.
7. Scalability: concept can be adapted for various sizes and varying loads.
8. Compliance: designed to absorb obstacles at speed up to 24 km/h without structural damage and minimize ground pressure. Please note that wheels able to withstand larger rocks at higher speed and have lower ground pressures will be given preferential ranking.
9. Load capacity: solvers should strive for higher load capacity designs to account for dynamic loading associated with desired higher speed operations. The minimum load capacity for this challenge will be  256 N per wheel. This is determined by a calculation of 2 × MicroChariot’s lunar gross mass (≈ 45 kg rover + 270 kg payload) distributed across four wheels under lunar gravity. This force is intended to cover expected loads under quasi-static driving conditions (i.e., slow speeds, weight distributions) and represents the minimum bar for this challenge. Solutions that can withstand larger masses, drive at greater speeds, or with greater load distribution variability, will be given preferential ranking.
10. Traction: propel rover over 20° slopes, rocks, crater rims, and in loose soil. Please note that proposals that demonstrate the likelihood of higher tractive performance will be given preferential ranking.
11. Simplicity: few parts, minimal fasteners, straightforward assembly, low-maintenance, uses broadly available materials and standard fabrication techniques. Provide a rough cost for the manufacturing of a single wheel of your design.
12. Long service life: target design life up to 1,000 km in lunar environment. Please note that proposals that demonstrate the likelihood of a longer wheel service life will be given preferential ranking.

Submissions that meet all Must-Have items will be judged competitively on the Desired Attributes they achieve and how well those strengths are documented in the whitepaper.

Judging Criteria

Submissions will be assessed based on the following factors. As this is a down-select challenge, detailed phase 2 and 3 judging criteria will be released to phase 1 and 2 finalists at the start of each subsequent phase.

• Phase 1 (Ideation) Criteria:

• Phase 2 (Prototype) Criteria: Evaluation will assess the functionality of the delivered prototype, the quality of construction, adherence to the submitted design, and results from any self-conducted testing or demonstration via video submission.
• Phase 3 (Demonstration) Criteria: The primary evaluation will be based on the prototype's performance during the live demonstration at the NASA Rockyard and the team’s presentation of their wheel development. The Rockyard Evaluation includes results from durability testing and traction performance to propel the vehicle and traverse obstacles.

Submission

Phase 1 (Ideation) deliverables are a CAD model and whitepaper (approximately 7 pages). Your deliverables will be submitted via electronic form and will need to provide the following information:

• Title
• Two-sentence short description
• Publicly releasable abstract that introduces your team and your idea without revealing proprietary details
• Objective measurements of your wheel’s design and its projected performance, including Mass Budget using format provided in Table 1 and Speed vs Rock Size performance using format provided in Table 2
  • Note for Mass Budget: The confidence level columns in the provided mass budget table are included to capture and understand your confidence in the various components’ masses, based on your research and assumptions, see example entries in Table 1 below.
  • Note for Speed vs Rock Size: The values in the table are meant to indicate the speeds at which your wheel can operate while rolling over various size rocks and under various loads. The rock size of 0 indicates maximum speed. For example, “⅛” indicates rolling over a rock that is ⅛ the diameter of your wheel.
• Narratives to support and justify stated measurement projections, and to address Phase 1 Desired Attributes and the sections outlined in the Phase 1 Judging Criteria
  • Note: Narrative sections are organized to follow Judging Criteria - Phase 1 (Ideation) Criteria structure and thus inputs should use questions in criteria as guidance to inform responses.
• CAD model
• Optional images
• Curriculum Vitaes (CV) or Letters of Support (if applicable)
• Link to a short build and/or simulation video (if applicable)

Table 1: Mass Budget Table with example entry

Table 2: Speed vs Rock Size Table

Phase 2 and 3 submission requirements will be provided to phase Finalists at the start of each subsequent phase.

Rules

Participation Eligibility:

The Prize is open to anyone age 18 or older participating as an individual or as a team. Individual competitors and teams may originate from any country, as long as United States federal sanctions do not prohibit participation (see: https://www.treasury.gov/resource-center/sanctions/Programs/Pages/Programs.aspx and https://www.acquisition.gov/far/52.225-5). If you are a NASA employee, a Government contractor, or employed by a Government Contractor, your participation in this challenge may be restricted.

Submissions must originate from either the U.S. or a designated country (see definition of designated country at https://www.acquisition.gov/far/part-25#FAR_25_003), OR have been substantially transformed in the US or designated country prior to prototype delivery pursuant to FAR 25.403(c). 

Submissions must be made in English. All challenge-related communication will be in English.

You are required to ensure that all releases or transfers of technical data to non-US persons comply with International Traffic in Arms Regulation (ITAR), 22 C.F.R. §§ 120.1 to 130.17.

No specific qualifications or expertise in the field of rovers is required. Outside individuals and non-expert teams to compete and propose new solutions.

To be eligible to compete, you must comply with all the terms of the challenge as defined in the Challenge-Specific Agreement.

Intellectual Property

HeroX will provide prize-winning solutions to the government under unlimited rights as specified in clause FAR 52.227-14 Rights in Data–General (April 2015). Unlimited rights means the rights for the Government to use, disclose, reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly on the web or elsewhere, in any manner and for any purpose, and to have or permit others to do so.

You may be required to complete an additional form to document this license if you are selected as a winner.

Registration and Submissions:

Submissions must be made online (only), via upload to the HeroX.com website, on or before November 4, 2025 at 5pm ET. No late submissions will be accepted.

Selection of Winners:

Based on the winning criteria, prizes will be awarded per the weighted Judging Criteria section above.

Judging Panel:

The determination of the winners will be made by HeroX based on reviewby relevant NASA specialists.

Additional Information

• By participating in the challenge, each competitor agrees to submit only their original idea. Any indication of "copying" amongst competitors is grounds for disqualification.
• All applications will go through a process of due diligence; any application found to be misrepresentative, plagiarized, or sharing an idea that is not their own will be automatically disqualified.
• All ineligible applicants will be automatically removed from the competition with no recourse or reimbursement.
• Innovator is responsible for shipping prototype in Phase 3. International participants are required to manage all requirements regarding US customs for Phase 3 shipping of solutions. Prototypes will not be returned.
• No purchase or payment of any kind is necessary to enter or win the competition.
• Void wherever restricted or prohibited by law.