Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Design of a Data-Logger for Acceleration and Direction

Status
Not open for further replies.

R.Duke

Newbie level 3
Joined
Apr 5, 2015
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
61
I am trying to choose components and design a data logger for tracking the acceleration and direction/heading of a car.
The design needs to meet only a few requirement specifications and i don't need to concern myself with the software implementation.

The system needs to record direction of travel and acceleration every ten seconds and store it in an appropriate memory location with a timestamp.
It also needs to be able to upload this data to a PC.

I was thinking I will use a PIC18 and copy the circuit of a Ready for Pic board I already have from Mikroelektronika.
That will take care of the oscillator and power supply to the micro derived from a battery pack.

However I am looking for advice pertaining to the additional components and interfacing methods.

A 2-axis accelerometer was considered but would a 3-axis be better? I assume the heading can be extrapolated from the acceleration on each axis.
I guess that an analogue output is also desirable?

use a real time clock module seems appropriate for the timestamp, though the interfacing method is not chosen.

An SD card was considered for data storage though again, i have not looked into the interfacing method (spi or what).

Is it likley that my RTC will require i2c and the SD card will require SPI?

I was thinking of allowing serial transfer over ftdi for real time viewing, but im unsure about the ability to implement all 3 interfacing methods on the one chip simultaneously.

Any tips or assistance is greatly appreciated!

Thanks!
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,489
Helped
14,048
Reputation
28,351
Reaction score
12,706
Trophy points
1,393
Location
Bochum, Germany
Activity points
276,162
An accelerometer isn't suitable to derive travel and heading information. It would be even difficult to track the movement with a gyroscope. If you want this information, think about a GPS receiver.

Is it likley that my RTC will require i2c and the SD card will require SPI?
Yes. Chose a PIC with respective hardware interfaces for your convenienece, e.g. a recent 18FxxK chip. Or use hardware SPI and software I2C with an older single MSSP PIC.
 

R.Duke

Newbie level 3
Joined
Apr 5, 2015
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
61
given that i only require acceleration and direction of heating, i considered GPS to be a bit overkill.

What about an accelerometer with a magnetometer for direction?
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,489
Helped
14,048
Reputation
28,351
Reaction score
12,706
Trophy points
1,393
Location
Bochum, Germany
Activity points
276,162
Travel is the double integral of forward acceleration. Calculate how the error increases with time for your preferred acceleorometer device and check if it's acceptable.
 

R.Duke

Newbie level 3
Joined
Apr 5, 2015
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
61
I will not be implementing the software side of this project.

I will simply be designing the hardware.
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,489
Helped
14,048
Reputation
28,351
Reaction score
12,706
Trophy points
1,393
Location
Bochum, Germany
Activity points
276,162
Isn't it that any project should start with a feasibility consideration?
 

R.Duke

Newbie level 3
Joined
Apr 5, 2015
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
61
of course.
I am simply stating that any development with a hands-on approach is beyond the scope of this post.

Thanks
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top