Unsolicited SMSs

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The other day I received, what I consider, a spam SMS. Generally I would have just ignored it and carried on my with life, but not now. Not during exams, when I have time to do something about it.

The message was a general SMS here to receive XYZ, SMS stop to unsubscribe.

So I searched a bit for the numbers in the SMS but never came up with anything. Further searches relating to spam messages returned information on WASPA (Wireless Application Service Provider’s Association). They’re kind of like the Broadcasting Complaints Commission of bulk mail. But apart from a list of registered and affiliated parties, didn’t help much.

waspa.org.za

I also came across DMASA (Direct Marketing Association of South Africa). They have an opt-out service which requires all DMASA members to check through this list before contacting you with messages (register here). If your names on the list, they won’t contact you [1]. This is great, but not what I wanted. I wanted to know who had contacted me and why they thought they could. So I searched further.

Eventually I came across this website. It’s linked to WASPA and allows you to search a number in their database. Searching for SMS number returned Cael Media. A bulk-sms service company. I sent them a message requesting information on where they got my number.

I received a very fast reply from an employee asking for my phone number and assuring me I’ll be removed from their database and that I’d be provided with the information I requested the following day.

The one great thing is that WASPA take their job very seriously, and it appears that most bulk messaging companies are scared of stepping out of the WASPA code of conduct.

I got a heartfelt reply from Cael indicating that they’ve actually only just been WASPA accredited and are having some technical issues with their application. They offered me a refund on any expenses I may have incurred to settle the issue. I hadn’t incurred any costs, thanked them for the offer but re-stated that all I wanted was to know how they got my number.

A few days went by without any reply, so I sent an other email to them. I got a reply telling me they had got my details from Blackmoon Investments which allowed them to market to my mobile number. I haven’t been able to find out anything about Blackmoon investments, and further enquiries with Cael Media have been fruitless.

I also spoke with a friend about the situation and he showed me some communication relating to a similar issue he had had. After investigation and laying a complaint with WASPA, the company eventually revealed where they got his information. It had been bought from an overseas company. The cost of 5 million active emails and 6 million contact numbers came to $1000. Effectively R0.0007 per detail.

While I was busy on my mini-crusade, I figured I’d give Agrimark a piece of my mind as well. Since Christmas last year I had been receiving promotional SMSs from a British telephone number with specials at Agrimark. This makes matters slightly difficult, as the foreign number indicates that they are most likely not WASPA affiliated. The only email addresses I could find on their website were their branch managers, so I typed up an email to Agrimark Stellenbosch’s branch manager, basically asking to be removed from the list, and also enquiring where they got my info.

I received a very prompt, and very curt reply the next day telling me I’d been removed from the mailing list.

I replied thanking him for removing me, but that I still wanted to know where they got my number or who manages their bulk mail service. I never received a further reply.

[1] Note on the opt-out list. It’s managed by the DMASA. Some people don’t like the idea of giving their details to the very organisation which effectively manages direct marketing. Furthermore, adding your details to the list entails ID numbers, residential addresses, telephone numbers the whole lot. As a friend pointed out, you could have some fun at the bank with these details. And the big issue here is that the database was allegedly leaked, putting 39 000 people at risk of identity theft.

Design of a 2-axis, Continuous Rotation, Camera Control Platform

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This was the title of my final year project for my BEng (Mechatroics) degree at the University of Stellenbosch. It’s been a year, a loooong year, but at the same time it’s passed so quickly. I’ve probably spent more time on varsity work this year than in any other previous year, a combination of this skripsie, mechatronics and electrical design projects, interspersed between the year’s class requirements.

You can see a summary poster of the project here. And the full report here.

Skripsie is something very different to what we’ve done previously. We’re given a year to complete the project, which is a fairly long time. What I’ve appreciated is the fact that it’s the only major project we’ve been given to do individually. It’s not that I don’t like other people, it’s just that it’s sometimes nice to be able to do things my way. Most of the projects are put forth by lecturers, and they act as supervisors for the projects. I’ve been very fortunate with my supervisor and his continued support and enthusiasm for my project.

Final Product

Final Product

So what is it? Well it’s basically a turret that is capable of continuous rotation. You get a bunch of pan/tilt cameras on the market, but they all stop after 360textdegree or less. The department I did my project with had purchased several Basler a311fc cameras to play with and desired a platform they could use for tracking. It’s a very nice camera, good quality and capable of fairly high capture rates (50fps @ 640×480, 132fps @ 320×240) and comes with some nifty software (Basler Pylon Driver) to control it. So the major issue was to transfer data and power to the camera. I looked at a couple of wireless solutions but for simplicities sake eventually went with slip rings. Picked up 2 slip rings (at quite a cost, well I was surprised at the expense) from Moog.

a slipring

a slipring

Next issue was control. My control systems has never been the strongest, so decided to stick with some open loop control in the form of stepper motors. Picked up a 220Nmm and 440Nmm stepper motor to control the tilt and pan respectively. They’re bi-polar hybrid stepper motors with a 0.9textdegree step size. I drove them both in half-step mode effectively giving me 0.45textdegree accuracy. To drive them I made use of a combination of L297 and L298 ICs from ST.

The idea was to be able to control this all from a PC, so some software development and integration was also required. To bring it all together I made use of an Arduino Uno. I developed a GUI in Python which then communicated via a serial connection with the Arduino. I was originally going to use Java for this, but couldn’t get a serial connection running. Chatted to some friends who suggested Python and found this post with a nice example. For testing I also got hold of two AS5040 hall effect sensors from Austria Microsystems. These rotary encoders give a 1024bit resolution, effectively 0.35/textdegree. I managed to find some nice code for the Arduino to read the data via SSI over at RepRap.

CAD Model

CAD Model

This was also the first time I’ve had the opportunity to develop CAD models of something and have it built. We’ve done several machine design projects over the years, but they’ve all been conceptual only. I didn’t machine the stuff myself, but it was pretty cool when I built the thing, and compared it to my model, and it looked the same.

screenshot of the UI

screenshot of the UI

So I handed in the final report on the project today. Unfortunately it’s not working 100% at the moment, and one of the motor driver circuits got damaged, so I need to repair that before my presentation in a few weeks time.

But until then, it’s 3 exams in 3 weeks, so ought to be pretty chilled. And I’m almost an engineer o/

Karoo to Coast

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“Julle’s die mooiste mense!“, that’s the way my ride started off on Sunday as I completed my first Karoo to Coast bike ride. It’s 100km of almost purely dirt roads that takes you from Uniondale up and down the mountains to end off in Knysna.k2c

100km is a long way, and my constant self-reassurances that it must all be downhill (seeing as we started at 700m and ended at sea-level) did little to help when all the climbing occurred. Something that did help was the beautiful scenery, spectators with cheers of support, water points and a stunning 14km down hill. 14km. Of down hill. It was great!

Although the road wasn’t closed to traffic we were very lucky, along the entire 100km, I probably only encountered 2 or 3 non-official cars. This makes life on the down hills much nicer. Speaking of down hills, and up hills for that matter, and puddles, this is my only complaint, however it is not at all unique to the K2C.

I’m not the fastest climber, and as such I make a point to keep well left and out of the way of the faster riders. I’m also slightly paranoid, and constantly check around em to see where people are. If I want to pass someone I check to see I won’t get in someone’s way and I make a dash. All I want is for other people to do the same on the downhills. Downhills are where I can make up all the time I lost on the uphill. I’m comfortable going fairly fast on the downhills. It’s fun, but when you’re coming down and getting held up the whole time it get’s annoying, especially people who don’t hold their lines through a corner. Obviously cutting corners is the easiest way to get down fast, and I do it often, but I make sure I won’t be cutting someone else off.

Grabbed these off actionphoto.net they take great photos at all the events

My problem with puddles is more people’s lack of desire to get wet and muddy in an inherently dirty past time. About 15km into the ride there was a big puddle of water in the middle of the road and everyone tries to go around, half the people climbed off their bikes at this stage. I rode straight through the middle. Why? Because no one else was there, and it’s fun to make a spray of muddy water :)

Most of these problems are just an issue of too many people in the same spot, and is, I guess fully understandable, and I accept them as part of cycling, but it would be nice if they weren’t there.

In any case I cycled the full route with my dad and we finished with equal times of 05:36:08, nothing amazing, but I was quite happy with it. He did somehow manage to grab the position in front of me, us finishing 816 and 817 of 1987 finishers. The cutoff being 8hours. We also stopped for a nice swim in a river along the way to cool off on what was a rather warm day.

Although the race started in Uniondale, we spent the night at a nice B&B in de Rust, I believe the place was called Riverside or something similar. We had lovely pizza the previous night at the backpackers in de Rust whose restaurant is apparently only open on Fridays.

Included in this post are the logs from my GPS which I carried along, and which managed to die 15km from the end. Max speed clocked out at 66km/h.

Overall had a great ride on a spectacular route and look forward to doing it again next year.