CN114361884A

CN114361884A - CAN bus terminal resistor automatic matching design method for boxed missile

Info

Publication number: CN114361884A
Application number: CN202111683782.XA
Authority: CN
Inventors: 李欢丽; 李平; 吴超; 张杨; 荆广; 蔺子存
Original assignee: Xian Institute of Modern Control Technology
Current assignee: Xian Institute of Modern Control Technology
Priority date: 2021-12-27
Filing date: 2021-12-27
Publication date: 2022-04-15
Anticipated expiration: 2041-12-27
Also published as: CN114361884B

Abstract

The invention discloses a CAN bus terminal resistor automatic matching design method which is mainly used for automatically matching terminal resistors on a box missile at the farthest end when a launching system and a plurality of box missiles adopt CAN bus communication, and realizing the universal design of the box missiles while meeting the requirements of a CAN bus communication network on the terminal resistor setting. The invention adopts the design method of automatic matching, can realize the generalization of the boxed missile, and avoid the problems that the traditional design method needs to increase the resistance on the farthest boxed missile, thereby causing the non-generalization and the non-uniform technical state of the boxed missile; by adopting a simple mechanical and electrical combination mode, when the boxed missile is cascaded, the automatic open circuit of the resistor on the cascaded terminal is ensured, and the resistor on the terminal at the farthest end is in place.

Description

CAN bus terminal resistor automatic matching design method for boxed missile

Technical Field

The invention belongs to the technical field of electrical technology of weapon systems, and mainly relates to a CAN bus terminal resistor automatic matching design method for a boxed missile.

Background

When CAN communication is adopted, a terminal of a trunk line needs to be matched with a terminal resistor of 120 omega, in a weapon system based on a CAN bus, the CAN bus is adopted between a launching system and missiles for information interaction, when the launching system and a plurality of missiles adopt linear topological structure communication, the problem of setting the terminal resistor of a CAN bus network needs to be considered, the terminal resistor generally needs to be set at the farthest end, the traditional method is to set a matching resistor at the farthest terminal of a cable network, or independently design a terminal resistor connecting terminal to be connected on the missiles at the farthest end, or the missiles are designed into two types, one type does not have the terminal resistor and the other type has the terminal resistor, and when the missiles with the resistors are connected, the missiles with the resistors are placed at the farthest end, and the methods limit universality and have low expansibility.

Disclosure of Invention

The technical problem to be solved by the invention is that a self-short circuit/open circuit mechanism is designed, so that when missiles are cascaded, the matching resistance of a near-end missile is disconnected, and the matching resistance of a far-end missile is in place, and the convenience of use is greatly enhanced while the communication requirement of a CAN bus network is met.

In order to solve the technical problems, the technical scheme of the invention is as follows:

the terminal resistor automatic matching method designed by the method solves the problem of cascade connection of a plurality of boxed missiles, enables the terminal resistor to act on the far-end missile forever through mechanism design, improves the generalization degree, greatly reduces the external dependence degree, and enhances the convenience of operation.

The invention adopts a universal design for each case-packed missile: each box-packed missile is provided with a terminal resistor R1, a short circuit ring 1, a short circuit ring 2, a needle terminal 1, a needle terminal 2, a needle terminal 3, a needle terminal 4, a hole terminal 1, a hole terminal 2, a hole terminal 3 and a hole terminal 4.

The lower end interface 1 of each box-packed missile is a hole connector, the upper end interface 2 is a needle connector, and CAN H and CANL between the upper port and the lower port are connected through an internal cable.

When two missiles are cascaded, a lower end interface 1 of a box-packed missile 1 is butted with an interface of a launching cradle, and an upper end interface 2 of the box-packed missile 1 is butted with a lower end interface 1 of a box-packed missile 2; after a lower end interface 1 of a boxed missile 2 is in butt joint with an upper end interface 2 of the boxed missile 1, a needle terminal 1 of the boxed missile 1 is respectively connected with a hole terminal 1, a needle terminal 2 and a hole terminal 2 of the boxed missile 2, a needle terminal 3 and a hole terminal 3, and a needle terminal 4 and a hole terminal 4 of the boxed missile 1, a signal transmitted by the needle terminal 1 of the boxed missile 1 is CAN H, and a signal transmitted by the needle terminal 4 of the boxed missile 1 is CAN L; the terminal resistor R1 is 120 Ω, and R1 is connected to pin terminal 2 and pin terminal 3 to provide the matching resistance required for the CAN bus terminal.

When a certain missile is used as a tail-end node, a rear-stage connector of the missile is suspended, the pin terminal 1 and the pin terminal 2 are short-circuited by the short-circuit ring 1, and the pin terminal 3 and the pin terminal 4 are short-circuited by the short-circuit ring 2, so that 120 omega matching resistance exists at two ends of the pin terminal 1 and the pin terminal 4.

When a certain missile is used as an intermediate node, other missiles are cascaded with the missile at the later stage, a pin connector of the missile is inserted into a hole connector of the missile at the later stage, the short-circuit ring 1 and the short-circuit ring 2 move along with the movement of the position of the hole connector, the pin terminal 1 and the pin terminal 2 are insulated, the pin terminal 3 and the pin terminal 4 are insulated, and the short-circuit ring cannot short-circuit the missile, so that the matching resistance between the pin terminal 1 and the pin terminal 4 is automatically disconnected.

According to the invention, the self-short circuit/circuit-breaking mechanism CAN ensure that the near-end matching resistor is automatically disconnected when the boxed missile is cascaded, ensure that the far-end matching resistor is in place, and meet the requirement of a CAN bus on the matching resistor.

The invention has the beneficial effects that: the self-short circuit/break circuit mechanism designed by applying the terminal resistance automatic matching design method ensures that all cascaded box-packed missiles have consistent technical states, has universality and provides great convenience for joint debugging joint test production; the designed self-short circuit/open circuit mechanism adopts a simple mechanical and electrical combination mode, has high reliability and ensures the stability of missile communication performance; the economy is good, and the cost can be effectively reduced through the universal design.

Drawings

Fig. 1 is a diagram of an application of the method for automatically matching the termination resistance in the present invention.

Fig. 2 is an equivalent diagram of an application diagram of the automatic matching of the termination resistance in the present invention.

FIG. 3 is a schematic block diagram of an automatic terminal resistance matching method according to the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1, each of the box-packed missiles has a universal design, and the lower port 1 is a hole connector and the upper port 2 is a pin connector, and CAN H and CANL between the upper and lower ports are connected by an internal cable. When two missiles are cascaded, a lower end interface 1 of a box-packed missile 1 is in butt joint with an interface of a launching cradle, and an upper end interface 2 of the box-packed missile 1 is in butt joint with a lower end interface 1 of a box-packed missile 2.

As shown in the schematic diagram of fig. 2, after the lower end interface 1 of the boxed missile 2 is butted with the upper end interface 2 of the boxed missile 1, the pin terminal 1 (transmission signal is CAN H) is connected with the hole terminal 1, the pin terminal 2 is connected with the hole terminal 2, the pin terminal 3 is connected with the hole terminal 3, and the pin terminal 4 (transmission signal is CAN L) is connected with the hole terminal 4, respectively, after the connection, the short circuit rings 1 and 2 move, the pin terminal 1 is disconnected with the pin terminal 2, and the pin terminal 3 is disconnected with the pin terminal 4, so that there is no 120 Ω matching resistor between the pin terminal 1 and the pin terminal 4, that is, there is no 120 Ω matching resistor between the CAN H and the CAN L at the position of the boxed missile 1.

The boxed missile 2 is positioned at the farthest end, no connector is arranged on the boxed missile and is in butt joint with the boxed missile, and only the interface 2 of the boxed missile is a needle connector. The short circuit ring 1 short circuits the pin terminal 1 and the pin terminal 2, the short circuit ring 2 short circuits the pin terminal 3 and the pin terminal 4, and when viewed from the pin terminal 1 and the pin terminal 4, 120 Ω matching resistance exists between the pin terminal 1 and the pin terminal 4, that is, 120 Ω matching resistance exists between the CAN H and the CAN L at the position of the boxed missile 2. An equivalent diagram of an application diagram of the boxed missile is shown in figure 3, namely, a matching resistor of 120 omega is automatically formed at the farthest end, and the setting requirement of a CAN bus on the matching resistor is met.

The invention relates to an automatic matching design method of a CAN bus terminal resistor, which is mainly used for automatically matching the terminal resistor on a box-packed missile at the farthest end when a launching system and a plurality of box-packed missiles adopt CAN bus communication, and realizing the universal design of the box-packed missiles while meeting the setting requirement of a CAN bus communication network on the terminal resistor. The invention adopts the design method of automatic matching, can realize the generalization of the boxed missile, and avoid the problems that the traditional design method needs to increase the resistance on the farthest boxed missile, thereby causing the non-generalization and the non-uniform technical state of the boxed missile; by adopting a simple mechanical and electrical combination mode, when the boxed missile is cascaded, the automatic open circuit of the resistor on the cascaded terminal is ensured, and the resistor on the terminal at the farthest end is in place.

Claims

1. A CAN bus terminal resistor automatic matching design method for a boxed missile is characterized by comprising the following steps:

each box-packed missile has a universal design, the lower end interface 1 is a hole connector, the upper end interface 2 is a pin connector, and CAN H and CANL between the upper port and the lower port are connected through an internal cable;

2. The CAN bus termination resistance automatic matching design method for the boxed missile as in claim 1,

when a certain missile is used as a tail-end node, a rear-stage connector of the missile is suspended, the pin terminal 1 and the pin terminal 2 are short-circuited by the short-circuit ring 1, and the pin terminal 3 and the pin terminal 4 are short-circuited by the short-circuit ring 2, so that 120-ohm matched resistance exists at two ends of the pin terminal 1 and the pin terminal 4;