Cost Model

CostNav evaluates navigation policies through a comprehensive economic cost-revenue model grounded in real-world data. All parameters are referenced from industry sources including SEC filings, AIS injury reports, manufacturer specs, and delivery platform pricing.

For the full derivation, see Section 3.1 of the paper and the cost formula spreadsheet.

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Cost Framework Overview

The total profit of a navigation policy is:

\[ \mathbb{P} = \mathbb{R} - (C_{\text{CAPEX}} + C_{\text{OPEX}} \times N) \]

where \(\mathbb{R}\) is cumulative delivery revenue, CAPEX is upfront capital expenditure, OPEX is per-delivery operational cost, and \(N\) is the number of completed deliveries.

The contribution margin per delivery is:

\[ C_{\text{ContributionMargin}} = R - C_{\text{OPEX}} \]

where \(R = P_{\text{MktRobotDeli}} \times S_{\text{EpisodeTermSLA}}\) (base delivery fee x SLA compliance; zero if timeout).

The Break-Even Point (BEP) is the number of deliveries required to recover capital expenditure:

\[ \text{BEP} = \frac{C_{\text{CAPEX}}}{R - C_{\text{OPEX}}} \]

When contribution margin is negative (\(R < C_{\text{OPEX}}\)), the BEP is undefined --- the system is not economically viable.

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Capital Expenditure (CAPEX)

One-time fixed investments incurred before deployment.

Hardware Cost

\[ C_{\text{Hardware}} = P_{\text{Robot}} + (P_{\text{Lidar}} + P_{\text{GPS}}) \]

Parameter	Value	Unit	Reference
Robot Cost (\(P_{\text{Robot}}\))	8,000	$/robot	Retail price, Segway E1 delivery robot [21]
LiDAR Cost (\(P_{\text{Lidar}}\))	3,000	$/robot	Livox LiDAR for delivery robots [28]
GPS Cost (\(P_{\text{GPS}}\))	2,000	$/robot	RTK Device (with IMU) for delivery robots [28]

Sensor Configuration

Rule-based methods (Nav2) use Robot + LiDAR + GPS = $13,000. Learning-based methods use Robot only = $8,000 (CANVAS adds GPS = $10,000).

Data Collection Cost

For learning-based navigation, the cost of collecting training data:

\[ C_{\text{DataCollection}} = P_{\text{DataCollector}} \times S_{\text{DataCollectionTime}} \]

Parameter	Value	Unit	Reference
Data Collector Wage (\(P_{\text{DataCollector}}\))	33	$/hour	U.S. median hourly wage for data collection personnel [26]
Data Collection Time	65.63	hours	Total teleoperation hours in CostNav

CAPEX Summary (Table 3 from paper)

Component	Nav2 w/ AMCL	Nav2 w/ GPS	GNM	ViNT	NoMaD	NavDP	CANVAS
Hardware	13,000	13,000	8,000	8,000	8,000	8,000	10,000
Data Collection	0	0	2,165.79	2,165.79	2,165.79	2,165.79	2,165.79
Total CAPEX	13,000	13,000	10,165.79	10,165.79	10,165.79	10,165.79	12,165.79

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Operational Expenditure (OPEX)

Variable costs incurred on a per-delivery basis, directly influenced by navigation behavior. Organized into three categories: direct costs (electricity, repair), service costs (customer compensation), and liability costs (pedestrian and property damage).

Electricity Cost

\[ C_{\text{Elec}} = P_{\text{Elec}} \times \frac{S_{\text{AvgPower}}}{C_{\text{ElectroMechanicalEff}}} \times T_{\text{AvgDeliveryTime}} \]

Parameter	Value	Unit	Reference
Electricity Rate (\(P_{\text{Elec}}\))	0.2704	$/kWh	U.S. average retail electricity price [48]
Electro-Mechanical Efficiency (\(C_{\text{ElectroMechanicalEff}}\))	0.73	unitless	Derived: battery roundtrip (0.95) x motor (0.82) x inverter (0.99) x charge (0.95) [4], [41], [42], [56]

Repair Cost

\[ C_{\text{RepairRun}} = \frac{P_{\text{Robot}}}{N_{\text{RobotLifeRun}}} \times C_{\text{Repair}} \times \frac{S_{\text{EpisodeTermPhys}}}{C_{\text{PhysicalAssistance}}} \]

Parameter	Value	Unit	Reference
Useful Life of Robots (\(T_{\text{RobotLife}}\))	2	years	Expected operational lifespan per SEC filings [30]
Useful Delivery Run Count (\(N_{\text{RobotLifeRun}}\))	18,250	run/robot	Derived: \(T_{\text{RobotLife}} \times 365 \times N_{\text{Delivery}}\)
Repair Rate (\(C_{\text{Repair}}\))	10--20	%/year	Annual maintenance cost as % of robot price [13], [15], [36]

Service Compensation Cost

Failed deliveries incur compensation for customer refunds:

\[ C_{\text{ServiceCompRun}} = S_{\text{EpisodeTermSpoiled}} \times P_{\text{MktFood}} + (S_{\text{EpisodeTermTimeout}} + S_{\text{EpisodeTermPhys}}) \times P_{\text{MktRobotDeli}} \]

Parameter	Value	Unit	Reference
Market Robot Delivery Price (\(P_{\text{MktRobotDeli}}\))	3.49	$/run	Consumer delivery fee for campus robot services [47]
Avg Market Food Price (\(P_{\text{MktFood}}\))	31.93	$/run	Derived: \(P_{\text{Refund}} - P_{\text{MktRobotDeli}}\)
Avg Refund Price (\(P_{\text{Refund}}\))	35.42	$/run	Industry average order value for delivery failures [43]

Pedestrian Safety Cost

Modeled using the Abbreviated Injury Scale (AIS), measured from collision delta-v:

\[ C_{\text{PedestrianRun}} = \sum_{\text{AIS}} P(\text{AIS} \mid \Delta v) \times P_{\text{PedDamageAIS}} \times K_{\text{InjuryAdjustment}} \]

where \(P(\text{AIS} \mid \Delta v)\) is the probability of AIS severity given impact speed [51], and \(K_{\text{InjuryAdjustment}}\) adjusts for vehicle weight differences between the delivery robot and the crash report reference vehicle.

Parameter	Value	Unit	Reference
Avg Pedestrian Damage (AIS0)	380	$/event	Economic cost per MAIS pedestrian incident [3], [22]
Avg Pedestrian Damage (AIS1)	8,487	$/event	Same as above
Avg Pedestrian Damage (AIS2)	60,464	$/event	Same as above
Avg Pedestrian Damage (AIS3)	261,200	$/event	Same as above
MAIS Report Passenger Vehicle Weight	4,536	kg	Derived: 10,000 lbs = 4,536 kg, per MAIS Injury Report [51]

Property Damage Cost

Collisions with urban infrastructure incur repair or replacement costs:

\[ C_{\text{PropertyRun}} = \sum_j S_{\text{PropContact}_j} \times P_{\text{PropDamage}_j} \]

Parameter	Value	Unit	Reference
Mailbox Damage Cost	50	$/event	Municipal replacement cost [45]
Trash Bin Damage Cost	50	$/event	Municipal replacement cost [7]
Building Glass Damage Cost	300	$/event	Estimated repair cost [54]
Bollard Damage Cost	65	$/event	Estimated replacement cost [52]

OPEX Summary (Table 3 from paper, $/run)

Component	Nav2 w/ AMCL	Nav2 w/ GPS	GNM	ViNT	NoMaD	NavDP	CANVAS
Electricity	0.0029	0.0031	0.0005	0.0009	0.0003	0.0001	0.0027
Service Compensation	5.4021	10.1322	3.4900	3.1410	3.4551	3.4900	3.8910
Pedestrian Safety	29.3200	20.5800	11.6400	29.8900	9.7600	9.3000	14.3800
Property Damage	0.0000	1.0000	3.6500	6.0000	12.0000	0.0000	6.0000
Repair	10.8493	7.2329	5.2603	11.8356	6.9041	2.9589	6.5753
Total OPEX	45.5743	38.9482	24.0407	50.8675	32.1195	15.7491	30.8490

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Revenue

\[ R = P_{\text{MktRobotDeli}} \times S_{\text{EpisodeTermSLA}} \]

Revenue per delivery is the market delivery fee ($3.49), modulated by SLA compliance. Deliveries exceeding the timeout receive zero revenue. Food intactness determines service completeness.

Parameter	Value	Unit	Reference
Delivery Runs per Day (\(N_{\text{Delivery}}\))	25	runs/day	Reported daily throughput per robot, SEC filings [29]
Delivery Failure Rate (\(C_{\text{DeliveryFailure}}\))	0.06	%/run	Operational failure rate per SEC filings [29]
Operator:Robot Ratio (\(N_{\text{Fleet}}\))	4	robot/operator	Level 4 autonomy supervision ratio per SEC filings [29]
Robot Operator Wage (\(P_{\text{Operator}}\))	24	$/hour	U.S. median hourly wage for robot operators [27]

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Simulation-Measured Inputs

These values come from the Isaac Sim physics simulation and feed into the cost formulas above:

Parameter	Value	Unit	Reference
Robot Speed (\(C_{\text{RobotSpeed}}\))	6.00	km/h	Maximum operational velocity, Segway E1 spec [40]
Robot Max Speed (\(C_{\text{RobotMaxSpeed}}\))	12.80	km/h	Maximum nominal speed of Segway E1 [28]
Robot Weight (\(C_{\text{RobotWeight}}\))	50	kg	Maximum off-load weight, Segway E1 [28]
Avg Delivery Time (\(T_{\text{AvgDeliveryTime}}\))	0.3667	hr/run	Mean delivery duration from operational deployments [39]
Max Delivery Time (\(T_{\text{MaxDeliveryTime}}\))	1	hr/run	Maximum guaranteed delivery time [1], [37]
Avg Delivery Distance (\(T_{\text{AvgDeliveryDistance}}\))	4	km/run	Mean delivery distance per SEC filings [29]
Max Delivery Distance (\(C_{\text{MaxDeliveryDistance}}\))	6	km/run	Maximum operational delivery radius [38]
Charge Efficiency (\(\eta_{\text{charge}}\))	0.95	unitless	Estimated charge efficiency [41]
Battery Roundtrip Efficiency (\(\eta_{\text{batteryroundtrip}}\))	0.95	unitless	Estimated battery roundtrip efficiency [4]
Inverter Efficiency (\(\eta_{\text{inverter}}\))	0.99	unitless	Estimated inverter efficiency [42]
Motor Efficiency (\(\eta_{\text{motor}}\))	0.82	unitless	Estimated motor efficiency [56]

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Future Enhancements

Enhancement	Description
Cost-Aware Reward Shaping	Use the cost model as a reward signal for RL, enabling agents to directly optimize for profitability
Cloud Inference Costs	Model latency and bandwidth costs for cloud-based VLA policies
Dynamic Pricing	Adjust revenue based on demand, distance, time of day
Fleet Management	Optimize across multiple robots (routing, charging)
Traffic Rule Compliance	Factor in fines and liability costs from traffic violations

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References

#	Reference
[1]	AGV Network. Starship Technologies FAQs. FAQ page, 2024.
[3]	Association for the Advancement of Automotive Medicine. Abbreviated Injury Scale: 2015 Revision. Chicago, IL, 6 edition, 2018.
[4]	Battery Design. Round-trip efficiency of lithium-ion batteries. Battery Design article, 2024.
[7]	City of Hot Springs. Frequently asked questions. Solid Waste FAQ, 2026.
[13]	Jared Worth. Maximizing humanoid robot longevity: the power of maintenance-free components. igus Toolbox article, 2024.
[15]	Lucas. The ROI of autonomous mobile robots in your DC. Lucasware article, 2020.
[21]	Multirotors.store. Segway outdoor delivery robot. Store Listing, 2025.
[22]	National Highway Traffic Safety Administration. The economic and societal impact of motor vehicle crashes, 2019. Report No. DOT HS 813 403, 2023.
[26]	Salary.com. Data collector salary information. Salary.com listing, 2025.
[27]	Salary.com. Robot operator salary information. Salary.com listing, 2025.
[28]	Segway Robotics. Segway E1 robot specifications (E1 delivery parameters). Specification PDF, 2025.
[29]	Serve Robotics Inc. Serve robotics inc. form 10-k for fiscal year 2023. U.S. Securities and Exchange Commission. Available at SEC EDGAR database.
[30]	Serve Robotics Inc. Serve robotics inc. form 10-q. U.S. Securities and Exchange Commission, 2024. Available at SEC EDGAR database.
[31]	Serve Robotics Inc. Serve robotics inc. form 424b4 prospectus. SEC EDGAR filing, 2024.
[36]	Standard Bots. How much do robots cost? 2026 price breakdown. Standard Bots article, 2026.
[37]	Starship Technologies. Starship technologies launches commercial rollout of autonomous delivery. Press release, 2024.
[38]	Starship Technologies. Starship dimensions. Dimensions spec page, 2024.
[39]	Starship Technologies. Starship technologies celebrates one year of robot deliveries in Finland. Press release, 2024.
[40]	Starship Technologies. Starship robot technical specifications. Starship Deliveries industry page, 2024.
[41]	STMicroelectronics. GaN-based Li-ion Battery Charger Demo. Seminar PDF, APEC 2023.
[42]	Texas Instruments. TIDA-010056: 48V 3-Phase Inverter. TI TIDA design page, 2024.
[43]	The Restaurant HQ. Food delivery statistics. Article, 2024.
[45]	Town of Wrentham, MA. Mailbox damage claims (news flash). Article, 2026.
[47]	University of South Carolina. Grubhub and Starship delivery. USC Dining Services page, 2024.
[48]	U.S. Energy Information Administration. Electric power report. EIA electricity data page, November 2025.
[51]	Wang, J.-S. Mais(05/08) injury probability curves as functions of delta v. NHTSA report PDF, May 2022.
[52]	We Are Bollards. How much does it cost to install a bollard? Blog post, 2024.
[54]	Wittenberg University. Wittenberg university damage charge schedule 2024-2025. Damage Charge Schedule PDF, 2024.
[56]	ZAU. M250W Hub Motor Specifications. ZAU motor spec page, 2024.