The conversion we had made to Mr Jones roof by Alu-Cab in Cape Town by having it lift up when stationary, totally revolutionised the way we can utilise and live him. It has meant we have a “loft” area where we sleep and a downstairs section in which we can standup/sit in to change, cook, ride out storms, etc
The roof is designed to be lifted-up manually with the assistance of some very strong gas struts but of course we carry quite a lot of accessories on it and while we had increased the pressure in the gas struts and have for 4 years been manually opening it, it does still require a fair bit of muscle power to get it going. This was a concern for us, as Tania would not be able to open it if at some point in the future Stuart was to get injured or be sick and weak for a period of time.
Alu-Cab have various products for different vehicles and so when we saw they had an automatic opening solution for their canopy camper we got quite excited, unfortunately they did not have a solution for the Land rover Icarus conversion. So with no stock standard solution available our accountant/wannabe engineer decided Google was his friend and eventually found the world of linear actuators.
The concept of a linear actuator is simple, a small 12v motor drives a worm gear that as it turns lifts an object in a straight line. By reversing the polarity of the motor, the worm gear retracts. The actual application was however a little complicated as it was hard for us to assess the weight of the roof and therefore the size of motor required and secondly would we be able to attached the linear actuator at a suitable angle to allow for a straighline lifting considering the hinge action of the roof. In the end we purchased two actuators giving us a combined lifting power of 150kg.
Over the course of a few days we opened and closed the roof many times (manually) as we tried to figure out the optimum mounting positions and what brackets we would need to fabricate.
The two actuators are connected to a single “Double Pole Double Throw” (DPDT) toggle switch. This allows the polarity to be reversed by moving the switch up or down and thus operate the actuator.
The opening of the roof takes a little longer now, 1 minute instead of the previous 30 seconds, but that is really no issue considering it now requires zero effort. The actuators extend 600mm and once the roof has been lifted to that height all it requires is a gentle push and the original gas struts easily lift it the rest of the way.
This Link shows the actuator in motion.