ISO/TS 21815-2:2021

TECHNICAL ISO/TS
SPECIFICATION 21815-2
First edition
2021-07
Earth-moving machinery — Collision
warning and avoidance —
Part 2:
On-board J1939 communication
interface
Engins de terrassement — Avertissement et évitement de collision —
Partie 2: Interface de communication embarquée
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 5
5 Logical interface . 5
5.1 Logical groups . 5
5.2 Negotiation . 6
5.3 Initialisation . 6
5.4 Operation . 6
6 Physical interface . 7
6.1 General . 7
6.2 Machine connector . 7
6.3 CxD connector . 8
6.4 Override switch . 9
6.5 Physical layer .10
7 J1939 communication protocol .10
7.1 General .10
7.2 PGN:CxD»machine status .11
7.2.1 General.11
7.2.2 PGN description .12
7.2.3 SPN structure .14
7.3 PGN:CxD»MachineCommand .37
7.3.1 General.37
7.3.2 PGN description .37
7.3.3 SPN structure .39
7.4 PGN:Machine»CxDr eply .43
7.4.1 General.43
7.4.2 PGN description .45
7.4.3 SPN structure .46
7.5 PGN:Machine»CxDdata (PR OPULSION) .54
7.5.1 General.54
7.5.2 PGN description .55
7.5.3 SPN structure .56
7.5.4 PROPULSION subsystem .57
7.6 PGN:Machine»CxDstatus .62
7.7 PGN:Machine»CxDcommand .62
7.8 PGN:CxD»MachineR eply .63
7.9 PGN:CxD»MachineData .63
7.10 PGN:Time/ Date .63
8 Documentation .64
8.1 Machine documentation .64
8.2 System documentation.64
Annex A (informative) Communication sequences .66
Annex B (informative) Trust mechanisms .74
Annex C (informative) Implementation examples for override and standby modes .80
Bibliography .82
Foreword
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This document was prepared by Technical Committee ISO/TC 127, Earth-moving machinery,
Subcommittee SC 2, Safety, ergonomics and general requirements.
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iv © ISO 2021 – All rights reserved

Introduction
The increasing use of detection systems and avoidance technology has been supporting operators to
safely operate machines in the field of mining and construction. At the same time, there are demands to
set standards for machines and systems detecting, alerting and intervening to mitigate collision risk.
There are currently two existing standards in the field: ISO 16001 and ISO 17757. These standards
provide guidance for visibility aids and object detection systems and for autonomous and semi-
autonomous machines, however, there is currently no standard that describes collision risk awareness,
warning signals and collision avoidance actions of the machinery operated by humans where there is a
risk of collision.
Collision warning and avoidance systems are developing technologies; and the algorithms are not yet
mature and well understood. This document is intended to foster innovation and accelerate the pace of
improvements in new collision warning and avoidance technologies. The performance requirements of
this document are technology neutral and do not specify technologies to meet the requirements.
The systems described in this document are intended to assist the operator of the machine. As current
technologies are unable to achieve full collision warning/avoidance in every situation, the responsibility
for safe operation of the machine remains with the operator of the machine.
This document defines a protocol for communication between a machine and a connected device to
allow the connected device to command the machine to slow down, stop or to maintain a stationary
state where the machine can move in a linear (i.e. forwards-backwards) direction along a travel path.
Machines with rotational movements (e.g. excavators) and machines with compound movements (e.g.
machines with
...