Ultrasonic Sensor Data Transmission via Voltage and Current Modulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current ultrasonic sensor systems face limitations in data transmission rates and internal interference due to existing digital bus technologies like LIN and PSI5, which are not optimized for ultrasonic measurement systems, leading to inefficiencies and increased costs.

Innovation Solution

A method that combines voltage-modulated and current-modulated data transmission using a modified PSI5 data bus interface, allowing for bidirectional, fully digital communication at higher rates (up to 378 kbaud/s) with reduced self-interference, enabling efficient data transfer of ultrasonic echo information and features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If LIN bus is used for data transmission, then wiring harness can be simplified, but data transmission rate is limited to 20 kbit/s

Engineering Contradiction:
Improvewiring harnessVSAvoiddata transmission rate
Core Design Contradiction:
Device complexityVSSpeed

Solution Approach 1:

The patent combines voltage-modulated transmission (for commands from control unit to sensor) and current-modulated transmission (for data from sensor to control unit) into a single bidirectional communication interface, merging the advantages of LIN bus simplicity with PSI5 bus high-speed capability

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The communication interface is designed to perform multiple functions: voltage-modulated command transmission, current-modulated data transmission, and bidirectional communication, allowing a single interface to replace multiple separate connections

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Speed

If PSI5 bus is used for data transmission, then data transmission rate increases to 189 kbit/s, but self-interference during measurement increases due to high modulation current

Engineering Contradiction:
Improvedata transmission rateVSAvoidself-interference
Core Design Contradiction:
SpeedVSObject-generated harmful factors

Solution Approach 1:

The patent applies different modulation methods to different transmission directions: voltage-modulation for control unit to sensor transmission and current-modulation for sensor to control unit transmission, optimizing each direction for its specific requirements while minimizing interference

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The communication protocol uses periodic synchronization pulses and structured data frames with specific timing, allowing the system to manage transmission cycles in a way that minimizes interference with ultrasonic measurement operations

Inventive Principle:
Principle #19Periodic action

3Productivity

If bidirectional communication is implemented on the same data bus, then communication efficiency improves, but internal interference during simultaneous communication increases

Engineering Contradiction:
Improvecommunication efficiencyVSAvoidinternal interference
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The communication interface dynamically switches between voltage-modulated and current-modulated transmission modes depending on the direction of data flow, allowing flexible adaptation to different communication requirements while minimizing interference

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The protocol ensures continuous synchronization through regular SYNC pulses and maintains steady communication flow with structured data frames, preventing gaps or conflicts that could cause interference during bidirectional communication

Inventive Principle:
Principle #20Continuity of useful action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances data transmission rates, reduces internal interference, and simplifies the design, allowing for faster object detection and more efficient ultrasonic sensor operation with lower costs and higher precision, while maintaining reliable communication.

Implementation Method 1

The sensor emits an ultrasonic pulse and measures the reflection of the ultrasonic pulse caused by an object, i.e. its echoes. The distance between the ultrasonic sensor and the object is calculated using the measured runtime of the echo and the speed of sound.

Methodology Applied
Scientific EffectUltrasonic pulse emission and echo reflection: Ultrasound

Implementation Method 2

The distance between the ultrasonic sensor and the object is calculated using the measured runtime of the echo and the speed of sound.

Methodology Applied
Scientific EffectSpeed of sound: Speed of Sound

Implementation Method 3

data is current-modulated from the sensor to the control unit

Methodology Applied
Scientific EffectCurrent modulation:

Implementation Method 4

data is voltage-modulated from the control unit to the sensor

Methodology Applied
Scientific EffectVoltage modulation:

Data Source

PatentEP3084468B1Method for connecting a sensor
Publication Date: 2022.01.05 ROBERT BOSCH GMBH

AI summary

The invention relates to a method for operating a sensor system, in particular an ultrasound sensor system, comprising at least one ultrasound sensor and at least one control device. Data is transmitted in a current-modulated manner from the at least one ultrasound sensor to a control device. Data is transmitted in a voltage-modulated manner from the control device to the at least one ultrasound sensor.