Blog 2013/2014

Trainee blog

Welcome to Aros electronics trainee blog 2013/2014. This blog is maintained by Oscar Leon and Sebastian Holmqvist, two new M.Sc graduates straight out of Chalmers University of Technology, Gothenburg, Sweden. We started here at Aros electronics in late Aug. 2013 and will be working as trainees for a total of 12 months. This is our little adventure.

2014-11-11 - Trainee recap.

It's now been 15 months since I first joined Aros. The first 12 months has been as a Trainee where I've went through a number of different stages and gained vital practical experience in hardware design, familiarizing myself with our different software platforms and gotten my hands dirty in a few projects. I got to travel as an exhibitor to Nürnberg, Germany, to attend the SPS fair and then me and Oscar teamed up to create the now famous OddWheel for the Charm fair. Finally I topped it off with a total of 6 weeks in Kortrijk, Belgium, further introducing myself to the VdW group and their products.


2014-07-15 - Updates!

Hello there,

Since almost three months ago, I became HW responsible for one of our projects towards Volvo Busses. The project deals with the control of the wiping arms on the windshield. Conventional systems are typically controlled by mechanical linkage between the two wiping arms, forcing them to have some distance and therefore makes it "impossible" for them to collide. This solution however, requires much space in the already space constrained department in the front of the buss. The mechanics is furthermore one of the most common problems with the busses.

If it was instead possible to control the wiping arms by two separate motors, much could be gained. Therefore back in 2008, Aros began a cooperation with Volvo Busses to design and manufacture the next generation wiping control systems. The system consists of two brushed dc motors featuring sensorless estimation of the existing angle position. The pictures above illustrates the jig we have here at Mölndal and the aluminum enclosure of the PCB.


2014-06-23 - Back from Van de Wiele!

So my 6 weeks in Belgium are over and all in all it's been a great experience. Since the time of my last post I've managed to adapt to the working climate at VdW and have gotten to know some more people I'll continue to work with in one way or another, now that I'm back in Sweden.

So what's the summary of my stay?

  1. Belgians enjoy food (quantity) and beer (quality)
  2. The weather is really erratic
  3. I have my work cut out for me

When I went home I brought most of my work with me. On the left you see my lab station in Kortrijk with my collegue Wim helping me debug. On the right I'm back at Aros. Sadly, most of the things I've worked on haven't been introduced to the market yet, so this post will mostly contain photos of places and food.


2014-04-28 - First week in Belgium

As part of the Trainee program I've been sent down to Kortrijk, Belgium to work at Van de Wiele HQ for six weeks (actually, 3 + 3 weeks). So last tuesday I got up early in the morning, hopped on a plane and flew to Brussels where a taxi picked me up together with an Italian sales agent also visiting VdW.

For those of you who don't know, Aros is a member of the VdW group and does many of the drives for their various textile weaving looms. Just 10 years back, all the parts were mechanised and driven by one huge motor, transferring power via cardon shafts. In order to increase flexability and minimize downtime, several parts of the machine have been disattached and are now electronically synchronised and individually driven.


2014-04-03 - Company ski trip

Last week ended with a bus trip where over 100 Aros/Iro employees went skiing together! On thursday afternoon we filled two busses and started our journey up north to Trysil in Norway. 

The weather was absolutely amazing with 10-15 degrees and blazing sun. Almost every pause (beer stop) involved stripping down to your long johns making sure you soaked up the sun as much as possible.

I even rented a (ugly ass) helmet - safety first!


2014-03-21 - After 'After After Charm event'

Reentry in the HW division! During the last week, I've been involved in the first parts of a redesign/update project of the HW of one of our existing products. The product is used in a manufacturing process where it controls a three phase PMSM motor. For this application, the board is connected to the mains power supply, which after rectification yields a high voltage dc link of 400VDC (I have never been working with HV applications before).


2014-03-13 - After 'After Charm'

In the wake of After Charm I've returned back to helping out in various projects again. For instance, I was asked to evaluate a new type of inductive encoder (incremental and/or absolute) that would potentially be very cost effective. It's a 13 bit (in theory) chip of magic that's comprised out of a circular array of Hall sensors bundled with a two pole magnet that sits on top of the rotor axis. So far it's mostly been scrutinizing the data sheet trying to work out if it meets our requirements when it comes to fault tolerances and effective resolution.

As I need to test the sensor in the lab, I enlisted a collegue to help me with the mounting. We're talking offsets less than 2/10 of a mm so my original approach with a glue gun and popsicle sticks wasn't really an option ;) Using a motor with a pre-mounted incremental optical encoder I'll be able to compare it to an already valid solution.


2014-02-28 - After Charm resumé

Yesterday we had visitors. Around 3 pm, over 40 interested students gathered in our reception. We huddled them all up and started off with a company presentation and then moved on to describe some of the workflow involved in our motor design. After that, the students were divided up into groups and guided through both the production downstairs and then showcased some of the products in our labs.

The night ended with some food, drinks and a pubquiz. A big thanks to our house band of the night - The Office!


2014-02-21 - AfterCharm reminder!

Do not forget our AfterCharm event, which will be held here at Aros in Mölndal next thursday (2014-02-27).


2014-02-16 - Summary of OddWheel Project


2014-02-08 - Summary of CHARM!

Aros Electronics participated in Chalmers studentkårs arbetsmarknadsdagar, also known as CHARM event! We were located in the southen part of the V building, not that far from the exhibitors lounge :-) 


2014-02-03 - Presenting Aros OddWheel!

From the project start in early January, one month later we're finally finished! So without further ado, here it is - the Aros OddWheel!


2014-01-27 - OddWheel progress (cont'd)

Much effort has been put on the manufacturing parts of the project lately, were we've been visiting our company partner IRO and used some of their very nice machines and tools. The idea was to assemble the motor to the side of the chassis, connect it to the planetary gear (by axle shaft), lock the planetary gear axle with chassis, and let the gear spin synchronously with the rim. The center holes are for encoder and lock mechanism for gearbox. 


2014-01-27 - OddWheel progress

In between waiting for the manufacturing of the mechanical parts, I've set off with getting the 3-phase Permanent-Magnet Synchronous Motor (PMSM) running on Oscar's development board. Since the current rotor axis doesn't extend out the backplane I had to make a quick jig for mounting the encoder (the blue part) on the front. It's amazing what some screws and heat-shrink tubing can accomplish.

With some help from the guys at work I successfully got the incremental encoder working, set up an initial rotor alignment and successfully turned the motor using a speed controller. With some more tuning of the current controller we'll start working on the control loop for the actual OneWheel.


2014-01-21 - CAD design of OddWheel locked!

Progress of the Mechanical Assembly of the OddWheel project! The following are some snapshots taken during the development of the mechanical design and assembly done in Catia V5:


2014-01-03 - OddWheel Roll/Pitch estimator!

The Xmc Development Board was in addition to the Aros staff desired functionality/requirements, also designed to support an Inertial Measurment Unit (IMU). This device typically contains a gyroscope, accelerometer and sometimes a compass, resulting in 3,6 or 9 degrees of freedom respectively (x-,y-,z axis, accordingly). Having hardware support for these devices, typically the roll/pitch (and depending on application, yaw) angles can be calculated by simple geometry.

The IMU is redicously small. Seriously. 3x3mm!


2013-12-30 - Aros new pick and place machines! (Sidetrack)

Recently the company invested in a new Siemens ASM production line. It consists of four double-tray Pick-and-Place machines connected in series, together with tray feeders, operator stations, conveyors, etc. These are used to "populate" the PCB boards with all the components before sending them through the oven where they're "baked". With a theoretical speed of around 40 000 components per hour - that's over 10 components a second - they're pretty damn fast.


2013-12-20 - Start of Trainee Project!!

Already during the trainee interview, we were told by our Chief Technical Officer that one of the many things we got the opportunity to perform here at Aros, was to make a creative and technical project involving Aros motor control technology. This project will be carried out during the year, and act as a support column which the hardware and software parts of the trainee programme is based upon!

Inspired by Glenn and our colleagues Segway, we quickly decided that we wanted to do some kind of self balancing robot, but did not go into further details. The XMC development board was already in the requirement specification designed to be able to drive a large variety of motors and supply voltage. Therefore this board will be used as HW in our design project!

What can be a greater source of information than youtube/internet? We found this cool self-balancing skateboard:



2013-12-16 - Christmas spirits and DC I/O EtherNet

With most of December behind us, the office is buzzing with activity in order to meet all the deadlines before signing out for Christmas. It seems as if most of my collegues will make the most out of this Christmas' generous amount of "klämdagar".

This tuesday the whole staff was invited to Hamnkrogen at Gothenburg's own amusement park, Liseberg. Despite the missing snow (what's up with that?), if there's one place that really gets you into that Christmas spirit, it's Liseberg. The buffé actually stretched beyond my eyesight and I made sure to stuff my face full, as is customary :)


2013-11-29 - SPS/IPC drives fair recap!

Since a couple of years back, Aros Electronics has been represented at the SPS/IPC drives fair in Nüremberg in Germany. The fair is Europe's leading exhibition for electric automation, with 114,000 sqm, 1622 exhibitors and 60 000 visitors.


2013-11-22 - Software phase

With most of the hardware design done and our boards soon shipped to prototyping, we're leaving the hardware phase of the trainee program and now entering the software phase. Basically, this means we'll start to familiarize ourselves with Aros' real time embedded operating system, ArOS, try and make some code contributions to some on-going projects and learn everything there is to know about motor control, sensor fusion, field buses, etc.


2013-11-19 - XMC DevBoard - PCB components assembled!

Since Aros obviously needs to keep producing their high volume products, the time slot available for manufacturing of prototypes is limited. During the end of the PCB CAD I was slightly stressed that I would miss my time slot, but worked hard to finalize the design and send the gerber files away for board manufacturing in time.


2013-11-14 - XMC DevBoard PCB has arrived!

Just received the board from the supplier!


2013-11-10 - Back from vacation

This week I just got back on track after my vacation in Dubai. So while Oscar was submerged in CAD layout work, I layed by the pool and worked on my tan ;) I've recharged my batteries and this past week I've been a busy bee catching up.

Some time has passed since my last update, so I thought I'd show you the results from my own PCB layout.


2013-11-04 - XMC DevBoard PCB design locked

Just finished the layout for the XMC board. My colleagues from HW department gave me very good feedback, which I put into the pcb design.



2013-10-17 - Aros engineering school

During the autumn, Aros are running single day courses in SW, HW, motor control and marketing strategy. It feels good that some of the courses taught at univerisy can be to some use, but there are some new areas which was not considered in the school environment that was further adressed here. Basically it involves how industry solves problem and make robust solutions. After the courses it feels like I've gotten further familiarized with the Aros atmosphere, and how we choose to approach and solve problems and make sure that they do not happen again.


2013-10-04 - DC I/O EtherNet and SPS/IPC preparations

As part of my training I have been assigned to construct a PCB of my own. A generic board with 16 digital inputs and 16 digital outputs. It's nicknamed DC I/O EtherNet and is basically a new version of an older product. What's exciting is that this board will not only sport the new XMC platform, 3 electrically isolated zones and a switched power supply - it will also be compatible with the ODVA EtherNet/IP standard.


2013-09-26 - XMC DevBoard schematics

When starting designing the board, I knew that it could benefit some of the R&D department if Aros did create a prototype/lab board for internal use. The board would in addition be based on the new house processor, the XMC 4500 infineon cpu. The board would in addition be used by me and Sebastian for a display project at chalmers. Sounds fun! I've previously only designed two PCB's before, and these were made in a hobby-like fashion. I also have been using the Arduino platform for various projects, and now I got my opportunity to do something (hopefully?!) better, in an engineered type of fashion.

I started off with discussions with my colleagues, trying to ensure that I had collected all desired functionality before I even begin. I wanted to emphasize this because I knew it would be a lot harder to fit the functionality to an already designed board, than having all desired information from the beginning.

Having collected this data, I summarized the desired functionality in a typical Aros document "Requirement Analysis - ReqAnal". Who came up with this shortening?


2013-09-20 - Hardware phase

These past two weeks have included company internal courses in Requirement analysis/specification and Hardware construction. We also had a quick look at Safety at work. Speaking of safe work - thanks to a former employee, we conducted a field trip to Sweden's biggest Nuclear rector site, Ringhals. Going there on friday the 13th really spiced things up as we ventured into the transformer station of nuclear reactor 1.


2013-09-02 - First days - Up and running!

In the picture below you can see both Oscar (left) and Sebastian (right) posing with our house-robot Glenn. This is taken just a few weeks in as new trainees at Aros. In this post I'll try to summarize what these first few weeks involved.