Method and system for multi-hop path selection for mobile robots based on cloud platform

Patent metadata

Field	Value
Publication number	US-11071038-B2
Application number	US-201916672069-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Nov 1, 2018
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

This disclosure relates generally to a method and system for multi-hop path selection for mobile robots based on cloud platform providing an optimal path for end-to-end communication in the multi-hop network. Multi-hop path selection for mobile robots, conventionally performed at mobile robot end, may not provide an optimal path as mobile robots are unaware of the global scenario of the multi-hop network. Further, computation at mobile robot end is not an energy efficient solution. The disclosed cloud system communicates the optimal path to the source mobile robot to reach the destination mobile robot through the plurality of Access Points (APs). Multi-hop path selection for mobile robots, currently performed at mobile robot end, may not provide an optimal path as mobile robots are unaware of the global scenario of the multi-hop network. The optimal path computed at cloud system increases the life-time of robotics network there by increasing the efficiency.

First claim

What is claimed is:

1. A processor implemented method providing a cloud system ( 102 ) based dynamic path selection in a multi-hop network, the method comprising:
determining, by one or more processors ( 202 ) of the cloud system ( 102 ), an optimal path for establishing a communication between a source mobile robot (R s ) 312 and a destination robot (R d ) 314 among a plurality of mobile robots in the multi-hop network in accordance with a subnet information comprising a network map and a cost map, wherein the subnet information is received from a plurality of Access Points (APs) in the multi-hop network, and wherein the determined optimal path defines a multi-hop sequence of Access Points (APs), selected from the plurality of Access Points (APs), to enable the communication between the source mobile robot (R d ) 312 and the destination mobile robot (R d ) 314 ,

wherein, determining the optimal path comprises:
identifying, a plurality of paths for communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 by:
establishing, a forward link between the source mobile robot and the destination mobile robot by computing a forward link cost function at each Access Point (AP) starting from a first Access point (AP) among the plurality of Access points (APs) connected to the source mobile robot (R s ) 312 and a first set of intermediate Access points (APs) among the plurality of Access points (APs) that terminate at a second Access Point (AP) connected to the destination mobile robot (R d ) 314 , wherein the initial value of the forward link cost function at the first Access Point (AP) is set to zero; and
establishing, a backward link between the destination mobile robot 314 and the source mobile robot (R s ) 312 by computing a backward link cost function at each Access Point (AP) starting from the second Access Point (AP) connected to the destination mobile robot (R d ) 314 and a second set of intermediate Access Points (APs) among the plurality of Access Points (APs) that terminate at the first Access Point (AP) connected to the source mobile robot 312 , wherein the initial value of the backward cost function is set to the computed final forward cost function at the second Access Point (AP); and

selecting, the optimal path for communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 from the identified plurality of paths comprising the multi-hop sequence of Access Points (APs), wherein an end-to-end forward link cost function and an end-to-end backward link cost function computed for the selected optimal path is minimum, and an end-to-end Outage Probability value for the optimal path is minimum; and

communicating, the optimal path to the source mobile robot 312 by broadcasting the optimal path through the plurality of Access Points (APs) to establish communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 .

2. The method as claimed in claim 1 , wherein the cloud system 102 identifies the first Access Point (AP) associated with the source mobile robot (R s ) 312 and the second Access Point (AP) associated with the destination mobile robot (R d ) 314 , to compute the forward link cost function and the backward link cost function, from the network map provided by each Access Point (AP), wherein the network map of each Access Point (AP) provides a list of mobile robots connected to each Access Point (AP) and a list of Access Points (APs) connected to each Access Point (AP).

3. The method as claimed in claim 1 , wherein the forward link cost function for a current Access Point (AP) is computed by summation of forward link cost function of an Access Point (AP) in previous hop and a value of a Cost Function (CF) parameter between the Access Point (AP) in previous hop and the current Access Point (AP).

4. The method as claimed in claim 3 , wherein the cloud system ( 102 ) obtains the values of the Cost Function (CF) parameters for the plurality of mobile robots and the plurality of Access Points (APs) of the multi-hop network from the cost map received in the subnet information from the plurality of Access Points (APs) in the multi-hop network, wherein the Cost Function (CF) parameters are computed by each Access Point (AP) for communication link between each Access Point (AP) and the plurality of mobile robots, and each Access Point (AP) and Access Points (APs) connected to each Access Point (AP).

5. An cloud system ( 102 ) based dynamic path selection in a multi-hop network, wherein the dynamic path selection system ( 102 ) comprises:
a processor ( 202 );
an Input/output (I/O) interface ( 204 ); and
a memory ( 208 ) coupled to the processor ( 202 ), the memory ( 208 ) comprising:
a dynamic path selection module ( 212 ) is configured to:
determine, an optimal path for establishing communication between a source mobile robot (R s ) 312 and a destination robot (R d ) 314 among a plurality of mobile robots in the multi-hop network in accordance with a subnet information comprising a network map and a cost map, wherein the subnet information is received from a plurality of Access Points (APs) in the multi-hop network, and wherein the determined optimal path defines a multi-hop sequence of Access Points (APs), selected from the plurality of Access Points (APs), to enable the communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 ,

wherein, determining the optimal path comprises to:
identify a plurality of paths for communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 by:
establish, a forward link between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 by computing a forward link cost function at each Access point (AP) starting from a first Access point (AP) among the plurality of Access Points (APs) connected to the source mobile robot (R s ) 312 and a first set of intermediate Access Points (APs) among the plurality of Access Points (APs) that terminate at a second Access Point (AP) connected to the destination mobile robot (R d ) 314 , wherein the initial value of the forward link cost function at the first Access Point (AP) is set to zero; and
establish, a backward link between the destination mobile robot (R d ) 314 and the source mobile robot (R s ) 312 by computing a backward link cost function at each Access Point (AP) starting from the second Access Point (AP) connected to the destination mobile robot (R d ) 314 and a second set of intermediate Access Points (APs) among the plurality of Access Points (APs) that terminate at the first Access Point (AP) connected to the source mobile robot (R s ) 312 , wherein the initial value of the backward cost function is set to the computed final forward cost function at the second Access Point (AP); and

select, the optimal path for communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 from the identified plurality of paths comprising the multi-hop sequence of Access Points (APs), wherein an end-to-end forward link cost function and an end-to-end backward link cost function computed for the selected optimal path is minimum, and an end-to-end Outage Probability value for the optimal path is minimum; and

communicate, the optimal path to the source mobile robot (R s ) 312 by broadcasting the optimal path through the plurality of Access Points (APs) to establish communication between the source mobile robot (R s ) 312 and the destination mobile robot (R d ) 314 .

6. The cloud system ( 102 ) as claimed in claim 5 , wherein the cloud system 102 is configured to identify the first Access Po

Assignees

• Tata Consultancy Services Ltd

Inventors

• Karjee Jyotirmoy
• Rath Hemant Kumar
• Pal Arpan
• Varma Ashwini Kumar

Classifications

• Y02D30/70

  in wireless communication networks · CPC title

• H04W40/12 Primary

  based on transmission quality or channel quality · CPC title

• H04W40/246

  Connectivity information discovery · CPC title

• H04W40/22 Primary

  using selective relaying for reaching a BTS [Base Transceiver Station] or an access point · CPC title