
Don’t Let Me Down!
Offloading Robot VFs Up to the Cloud
Khasa Gillani∗†, Jorge Mart´
ın-P´
erez†, Milan Groshev†, Antonio de la Oliva†, Robert Gazda‡
Abstract—Recent trends in robotic services propose offloading
robot functionalities to the Edge to meet the strict latency
requirements of networked robotics. However, the Edge is typi-
cally an expensive resource and sometimes the Cloud is also an
option, thus, decreasing the cost. Following this idea, we propose
Don’t Let Me Down! (DLMD), an algorithm that promotes
offloading robot functions to the Cloud when possible to minimize
the consumption of Edge resources. Additionally, DLMD takes
the appropriate migration, traffic steering, and radio handover
decisions to meet robotic service requirements as strict latency
constraints. In the paper we formulate the optimization problem
that DLMD aims to solve, compare DLMD performance against
the state of the art, and perform stress tests to assess DLMD
performance in small & large networks. Results show that DLMD
(i) always finds solutions in less than 30ms; (ii) is optimal in a
local warehousing use case; and (iii) consumes only 5% of the
Edge resources upon network stress.
Index Terms—robotic, optimization, offloading, Edge
I. INTRODUCTION
NETWORKED robotic services are being adopted to en-
hance operational automation and performance in some
uses cases, e.g., assembly robots in Industry 4.0, or remotely
controlled robots. However, in such use cases, strict latency
requirements [1] are difficult to meet upon network congestion
or large latencies towards the servers hosting the networked
robotic services.
To overcome such limitation, recent works [2], [3] propose
to split the networked robotics functionality into Virtual Func-
tions (VFs), and offload them to servers with more computa-
tional resources. Offloading VFs of a robotic service implies
solving the VF embedding problem. A plethora of works in the
literature have tackled the problem during the last years using
artificial intelligence [4] and bin packing-alike heuristics [5].
The solutions guarantee that resources – e.g. bandwidth and
CPUs – are not exhausted, and typically minimize the latency
of the embedded service. Recent works have adapted the VF
embedding problem to robotic services – see [2], [3], [6]
– but failed to consider either the latency [2]; radio signal
quality [3], [6]; or robot mobility [3]. Consequently, the robotic
service may not fulfill strict service latency requirements,
suffer from low bitrates, or service disruption – due bad radio
connectivity/coverage.
∗Khasa Gillani is with the NETCOM Lab at IMDEA Networks Institute,
†Khasa Gillani, Jorge Mart´
ın-P´
erez, Milan Groshev, Antonio de la Oliva are
@Departamento de Ingenier´
ıa Telem´
atica, Universidad Carlos III de Madrid
‡Robert Gazda is with Future Wireless at Interdigital Inc.
This work has been partly funded by the Spanish Ministry of Economic Af-
fairs and Digital Transformation and the European Union-NextGenerationEU
through the UNICO 5G I+D 6G-EDGEDT and 6G-DATADRIVEN.
far Edge
Cloud
near Edge
service
v1v2
(a)
(b)
(c)
Fig. 1: Don’t Let Me Down! fosters offloading the robot
service VFs up to the cloud (a), yet preventing the cloud large
latencies (b) and running out of coverage (c).
To that end, in this paper we propose Don’t Let Me Down!
(DLMD), an algorithm that fosters offloading robotic VFs to
the Cloud to minimize the Edge usage while considering (i) the
robotic service latency constraints; (ii) the wireless connectiv-
ity; and (iii) robot mobility. DLMD fosters offloading the VFs
to the Cloud as long as the latency constraints are fulfilled, and
takes VF migration and radio handover decisions to prevent
large latencies and out of coverage situations – see Fig. 1.
II. DON’T LET ME DOWN!PROBLEM FORMULATION
In this section we formulate the VF embedding problem that
DLMD solves to take adequate offloading, migration and radio
handover decisions for robotic services. We consider a hard-
ware graph Gwhose vertices V(G)correspond to switches
and servers. Specifically, we consider the three tiers of servers
illustrated in Fig. 1a: Cloud, far Edge, and near Edge; each
with decreasing latency towards the robot, respectively.
The goal of the VF embedding problem is to offload robot
VFs minimizing the resource consumption at the Edge, and
satisfying the robotic service constraints. In the following Sec-
tions II-A to II-D we specify the robotic service constraints,
and in Section II-E we formulate the associated VF embedding
problem statement, and prove its NP-hard complexity.
A. Robot computational constraints
The VF embedding problem must ensure that the robot
VFs do not exhaust the computational resources C(n)of each
server n∈V(G):
X
v∈a(n)
C(v)≤C(n),∀n∈V(G)(1)
That is, the computational requirements of all VFs vassigned
to a computing node a(n) = {v1, v2, . . .}must be lower than
its available computational resources C(n). On top, it must
ensure that all VFs V(Si) = {v1, v2, . . .}of a robotic service
Siare offloaded at some computing node n:
X
n∈V(G)
P(v, n)≥1,∀Si∈ S, v ∈V(Si)(2)
arXiv:2210.14208v3 [cs.RO] 14 Feb 2023