In-store 'Sat-nav' up and working now in a Tesco branch - come and try it!

We now have a comprehensive 'sat-nav' system working INSIDE one of our Tesco stores!

The new service is able to show you where all your wanted products are on a store map, show you where you are on that map, and guide you round the store to pick up your products using the shortest route.

The prototype system is installed at the Tesco Extra, Romford (Gallows Corner) in north-east London, and we need to recruit a large control group of customers (including staff) who would like to try it out on their Android smart-phones.

Would you like to give it a go? If so apply to join our control group (info below) which will assess the accuracy and reliability of the service from a technical perspective.. If you're accepted, here is what you'll experience:

1. Install our prototype app on your Android smart phone (it's not in the Android Marketplace, you'll be sent a link to download it directly and you'll need to change a setting temporarily to allow non-marketplace apps on your phone to install it).
2. Build up a shopping list on it (just like you can with Tesco Finder).
3. Send that shopping list to another customer with the same app on their phone so they can go shopping on your behalf (so I'm happy for members of a household to be in the control group).
4. Head to Tesco Extra Romford (click for map link).
5. Start the app as you walk through the front door.
6. See a comprehensive store map with all the items in the shopping laid out on it.
7. Press a button and the app will find the shortest distance between the products and create a route for you.
8. Show you where you are on the map with a blue dot with an accuracy of within 3 metres.
9. Walk the store following the route. The blue dot will move around the map as you move around.
10. If you want to find any product 'adhoc', we'll find it in the store and show you where it is on the map. 

So now we need your help. If…

1. You live or work near Tesco Extra, Romford, and
2. You have an android phone with Android OS v2.2 or later installed on it, and 
3. You're prepared to change your phone's application settings temporarily to allow installation of apps from 'Unknown Sources' just while you install our app, and
4. You are prepared to run an R&D app and accept no liability from us if we cause your phone problems (although it doesn't do anything more than require access to your wifi and location-based services on your phone), and
5. You accept that the app, being R&D, is a bit geeky but you are prepared to fiddle and play with it, and
6. You accept the system, being R&D, may just not work from time to time.

...then I would love to hear from you.

To join the control group, write to our R&D project manager Ben Martin at ben.martin@techfortesco.com with subject 'SATNAV APP'. Ben (@realbenm) has been running this exciting project from the start, so he'll look forward to hearing from you. Indeed you'll receive further instructions in a few days after contacting us. In the message please indicate what make and model of Android handset you have, and the version of Android it is running.

The service is only available publicly to Android phone owners at this time, because we don't want the app in it's current state going into the public app stores. Only Android easily offers the ability to install apps from 'Unknown Sources'.

Please note that we won't be rolling this out to customers in general for a while because we have to think about how useful it's going to be. The system involves a lot of infrastructure installation in the stores so we need to get all kinds of people involved in thinking about the customer experience. It would be awful if we did all this work but few customers really used it.

We must also see how we would put the technology into our production applications and make it really easy for everyone to use. There's also the possibility that the infrastructure is not reliable right now.

This project is in R&D for a good reason, and we are allowed to prove the viability - or otherwise - of anything we might wish to offer our customers. Sometimes R&D is close to production, and at other times it is far away. 


Apologies to other companies offering this service who contacted me after my original blog post that kicked off this project. We've had to operate under strict NDA with our chosen provider and not even intimate there was a such as system under construction. Until now!

How to make "Sat-nav" work inside a Tesco Store

If you have been reading in the media about my proposal to have a form of in-store "satellite navigation"-style location based awareness for Tesco Finder app users, I thought I would take you on a dive into the sort of research we're doing to see if we can make this work.

Now we don't do 'tech' for its own sake so let's examine the use cases:

1. "As the customer, I wish to be guided to the product I am looking for in the store".
2. "As the customer, I wish to be alerted by my phone whenever I am close to a product I have stored in my shopping list".
3. "As the customer, I wish to be alerted by my phone whenever I am close to products on special offer that are similar to products in my shopping list".
4. "As the customer, I want you to show me a map of the store layout, and on it show where both I am and where all the products in my shopping list are located".

Wow, we need some good data to satisfy these requests! Let's see what we have:

1. We know where all grocery products are in every UK Tesco branch as long as it is bigger than an Express-sized format. This data is already provided to Tesco Finder users.
2. We are already obtaining good aisle and shelf location spatial data from software that is used by Tesco merchandising teams that creates planograms. We haven't made this live yet but it's looking good. Tesco Finder would take this data and draw out all the aisles on the screen. We're making sure we describe the layout using as few characters of data as possible (I hope other app writers think as carefully about your data plan limit and keep the amount of data transferred down as much as all Tesco app authors do).

So we know every product that every Tesco branch stocks, and where it is laid out spatially in that branch. We know what products are on special offer and what the nature of that offer is. We just need to update the Tesco API server interface to make the spatial/map data available in as few characters as we can, and code a version of Tesco Finder to support the store map. That work is in progress, and we have found everything we need to make it work.

So "all" that is left now is to work out where the customer is, on a phone that loses the GPS signal as soon as they enter the Tesco branch. Hmmm...!

As you can imagine, all of our Tesco stores have wifi wireless network access points built into various parts of the building. These provide staff with the ability to enjoy network connectivity from their various handheld devices as they go about their tasks, so this is a critically important part of our in-store infrastructure.

Each access point has a unique identifier - a Media Access Control (MAC) address - which it supplies in every piece of signal data it transmits. We can tune into the wireless data chatter and read the MAC address without actually having to connect the phone to the access point. Indeed the phone doesn't have to transmit anything - just listen.

If we were to:

1. Tell the phone (using the API) where the access points are on the store map and what their unique MAC addresses are, and
2. Get the phone to measure the relative signal strengths of the wireless signals coming from these MAC addresses...

..then we could get the Tesco Finder app to work out where it thinks it is on the map.

Some fairly simple mathematical formulae is all that's required but given that a picture paints a thousand vector symbols, you can see how it would work in this diagram (click image for larger version):

I have colour-coded 6 access points so you can see how the phone might work out where it is in the store. Given that the lower signal strength is most likely to mean a more distant access point, and because the phone knows where all the access points are located, it can work out where it is.

Job done? Not quite... radio waves are a finicky phenomenon (I should know as I am a licensed radio amateur). From a radio point of view, Tesco sells a diabolic mix of products that reflect, refract and absorb signals. As the phone moves around, these three corrupters of signal purity will be in full force wrecking the ability of the app to work out where it is.

For example, walk down the aisle full of bottled waters and it is quite possible that nearer access points will become weaker than more distant ones as these stronger signals are absorbed more by the water. Walk down the baked bean aisle and those tins are reflecting signal like you wouldn't believe. These rarely affect the staff equipment since the system allows staff devices to roam quickly between access points. It's only us who needs to know about each particular access point. 

So now you know why this an R&D project. Tesco Finder needs to work out (probably through some sort of averaging) where it thinks it is in a way that is quick and accurate enough to be credible to the customer. If we crack this, it means that we can provide in-store "satnav" style help with zero change in the infrastructure. We're going to have a damn good go!

P.S. Once again can I point out to journalists that I am Head of R&D for Tesco.com (which just so happens to that part of Tesco pushing apps out in an R&D context). I am not Head of R&D for Tesco. Somebody else is!