Technical: How we built the Halsema

By Dennis Bouwers

When Motorhome-World (MH-W) first had the opportunity to create the project we call “Halsema”, we also wanted to do something special with the electronics.

MH-W has always been at the forefront of motorhome-building techniques and other technology in our industry. With the Halsema project, we incorporated some of the trends from the European sector, moving to touchscreens to control items installed in the motorhomes, or just to get information.

But we wanted to go a step further. We wanted the tablet to do almost everything.


One of the first items that our team was quite enthusiastic about, and that quickly became a “must-have,” was that the tablet must be used for driving functions like radio and GPS; it also had to be removable to be used outside whilst setting up camp.

We then had to find out how to have the tablet talk to the motorhome systems. We did quite extensive research to ultimately find a solution that could withstand the conditions that our clients would find themselves in. We ended up in the USA, where we found a company that specialises in manufacturing wireless-control devices.

The next step was to decide on the type of wireless connection that we needed. This was a crucial step in the process. We needed to think about redundancies in the system, and what could fail, and how the client would overcome the failures.

An app-based system – whether Bluetooth of Wifi – could prove to be an issue out in the bush. With a Bluetooth connection, if the tablet failed, you would have to pair the devices and download the app. We liked the WiFi connection, but again, the app was going to become an issue.

Finally, we decided on an Ethernetbased electronic relay board with an onboard web server module. This meant that we could design and write a website with buttons and gauges, connect the board to a local area network that we planned for the motorhome, then connect the entire system to a LTE router and BANG! Done!

Any device could connect to the local WiFi signal on board, even without an internet signal. Then you can connect to the website and control the motorhome. Tablet, smart phone, laptop… all would work without the need to install any additional software on any device.


In order to be able to display the motorhome’s information on the tablet (for instance, the water level, fuel, etc), we needed an electronic board (relay board), and an analogue to digital board.

An analogue to digital board is an electronic board that takes an analogue signal – in our case a 05 volt signal – and converts the signal to a digital format that the webpage could use to display the value in a gauge, or bar-like, graphic.

To explain the difference between analogue and digital signals, I will try the following explanation:

The needle fuel gauge in your car will be an analogue gauge, receiving a signal from your tank-level gauge in voltage. When you look at the LCD screen that tells you your range before you need to refuel, that is a digital signal. Your onboard computer receives an analogue signal from the fuel tank about how much fuel you have, and, after converting and computing, sends a digital signal to the screen to tell you how far you can drive. The computer is then acting as an analogue-to-digital converter.

We were going to use the analogueto- digital board (A/D board) to read and display items like the Diesel level in the sub-tank, and the temperatures and pressures in air suspension.


The creating of the local area network (LAN) was not difficult: we purchased the LTE router, pure sine wave inverter and network switch locally. The LTE router was going to act as the Wi-Fi access point as well.


Choosing the actual tablet was an easy decision. We asked the client for his preference of Apple or Android and he chose Android. So, the obvious choice was the latest Samsung 10.1 inch tablet.

Then came the big realisation that the tablet needed to be mounted, so that it could be easily and safely used while driving.

After this step, it seemed that all the hardware had been decided on and chosen. All we needed were the actual sensors − and, of course, a website.

Halsema Images


We appointed a couple of young and excited web developers to create a website for us that would look and feel the part.

The website needed to be intuitive and easy to use. We also needed big buttons as “switches”, to be safe while driving. A quick glance and the push of a button are all that is needed. The website ended up with 4 pages:
• A driving page to have all items readily at hand while driving.
• A camp page that has all items needed to set up camp.
• An information page – all gauges neatly in a row to be viewed easily.
• The air suspension page – here you can view and change to air suspension to allow the motorhome to lift and drop in height as needed.

This website was installed on the smallest web server I have ever seen installed on the web relay board. As long as there is power to the relay board and the WiFi router, any device could connect to the motorhome website. The system is protected by password, so that the campsite neighbour won’t be able to lower the roof on top of our client during the night, either accidentally or when playing the fool.

To be able to choose the sensors, we needed to finalise the list of items we needed to control, or information we wanted to display. This meant coming back to reality. This was the meeting during which all ideas had to be able to become real. Any idea about controlling some motorhome system with a firm plan on how to get it done was accepted to the list; any item that could not be made a reality was dropped.

So, here is the final list of those that made it to reality.

• GPS whilst driving. We purchased and downloaded the Tracks 4 Africa app, and that was done.

• Full music control. This was done by researching a system that would play music through speakers throughout the motorhome, to be listened to during travelling and while camping.

• We found a Bluetooth amplifier that would connect to the tablet and had an auxiliary input, so that we could connect the DStv decoder to the amplifier as well.

• We added some good-quality speakers and we had sound. We were very pleased with the end result. It was not too much, but not too little, either. Just so.

• Tyre Pressure Monitor System (TPMS). Some other IVECO 4×4 owners might know already that the standard rims of the IVECO 4×4 do not easily allow a TPMS system to be installed. We had to import new rims from Australia and add new Hankook tires to the Halsema to allow an internal Bluetooth TPMS to be installed. We downloaded the app for it, and we had a TPMS on the tablet, available to be viewed at any time.

• Diesel transfer switch. As on most of MH-W Discoverer Xtremes, we installed a diesel sub-tank and a transfer pump to fill the main tank from the sub tank. We used one of the relays on the relay board to activate the transfer pump and start the diesel transfer.

• Cameras. The front page of the website had “virtual buttons”. These buttons did not occupy a physical relay, but we used these to switch the view between 3 IP cameras. There was a camera for reversing, one for the roof − to see obstacles not high enough for the motorhomes – and one camera pointed at the front left wheel so that the driver can keep an eye on where the front left wheel is located on the path, when traversing narrow or dangerous paths.

• Lift roof button. This is the first button on the camp page. It is amazing to watch people’s faces light up in disbelief when this button is pressed. The lift roof is honestly one of the best projects I have ever been a part of.

• Alden satellite system. To protect the dish, we mounted it vertically on the rear of the motorhome. We added an electric actuator, so that with the press of a button (on the tablet, of course) the entire platform rotates 90 degrees and the dish is ready to be used.

• Outside light. Also attached to the relays on the board, it is easy to switch the light on and off when needed, without having to leave the braai.

• Fiamma awning. The range comes with the ability to motorise them, so adding this option to Halsema was a natural step.

• Entry step. As most of our Discoverer Xtreme customers would know, the double entry step is motorised and operated by using a button on the inside. On Halsema, we duplicated this button on the tablet camp page.

• TV lift systems. We managed to procure the best and most silent TV lifts. We had to bring them in from the US as well, but I tell you, they’re fantastic… absolutely fantastic, and you’ll love them! There is a television at the bedside, and one in an outside hatch, in front of the outside bar.

• Air suspension. We had a solenoid valve system supplied by the client, and although we had to do some modification to the actual system to make it perform through our relay switching board, it works very well through the tablet. There is an up and down button for each wheel corner of the vehicle.

• Coupled with the air-suspension system, we added the compressor on/ off switch on the tablet.

Next were all the info sensors that worked through the A/D board. In the end, these included:

• Diesel sub tank fuel level
• Water tank level
• Amp (current) meter for 12v DC. This one is quite handy as it shows you whether you are draining or charging the house batteries
• Fridge inside temperature
• Freezer inside temperature
• Outside / inside ambient temperature
• Air suspension pressure in all 4 corners
• Camper battery voltage
• IVECO battery voltage
• AC voltage (camp site plug voltage)


We also had to build in a manual override, in case something happened to the tablet or any other device. There needed to be a manual switch for each of the items controlled by the tablet. We thought it wise also to add some analogue dials to show some of the info displayed by the tablet. So, even if all technology fails, there are still buttons to control all items.


When we had all our electronic boards, drawings, sensors and connectors, it was up to our magicians to climb into the physical work and install all the designed dreams and aspirations.

And magic they performed. MH-W’s electricians really came to the party. They took on the mammoth task of taking all that was in our heads and installing it onto Halsema.

The end result was what we wanted: all the control and information-viewing of a motorhome via a tablet. Motorhome- World made this a reality.

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