If you want to build a new house, buy a car and let your son marry the prettiest girl in the village by growing vegetables, you must go against the seasons. People who buy vegetables are no longer refugees of the Great Leap Forward who would eat anything on the table. They are smarter and pickier than a cat.

Only when you stimulate their experienced tongues with something unusual will they be willing to part with the money in their wallet.

So you have to go anti-seasonal - and to do that you need a room that is cool in summer and warm during the winter.

Plastic membranes alone are not enough. You need to put straw mattresses on top. In summer you must put them on before the sun rises to keep the heat out; in winter before the sun sets to prevent heat from escaping. And you have to repeat the exercise every day.

The smallest mattress, before it is soaked with moisture or snow, weighs more than 10kg. A medium-size vegetable farm like mine needs hundreds of them. I don't need to describe how hard and painful it is to wake up before sunrise on a windy and freezing morning in January and drive your entire family - from the oldest daughter to the youngest son - out of bed to go to the fields.

Just ask around in the village how many people have abandoned growing vegetables out of season simply because they could not stand the hardship.

My machine relieves farmers of painful hard work. They only need to hit a switch and the rest of the work - whether you want the mattresses to go up or down - will be carried out automatically.

I call it Wang's robotic arm because I found that my design is quite similar to the robotic arm that they use on a space shuttle to build the International Space Station.

How does it work?

My machine is a truly mobile straw-mattress manager. A household that has a motorcycle can power it anywhere, any time.

It is not the first machine designed to help with the backbreaking job of moving mattresses. The Shandong government asked university professors to help, and two years ago they came up with a machine.

But few farmers are willing to buy it. That's not because farmers are poor and thrifty. They know the profit from growing vegetables out of season would more than pay for the initial investment.

Their reluctance is because the machine is impractical - it operates on alternating current, or mains power. Only a university professor could design such a thing because anyone who knows farm work would know it is impossible to find power lines out in the fields.

My idea involves a motor powered by direct current, so the batteries on motorbikes - which are very common in most villages - can be used.

And I have created a mechanism that raises and lowers the mattresses just like rolling the blind on a window up or down.

When I first told other people about my idea, no one believed it would succeed because they couldn't see how a small battery, used to power headlights and sound a horn, could be strong enough to lift up and lower straw mattresses.

Of course, it is impossible with the government's motor because it is heavy, is bulky and uses a form of power not available in the fields.

My motor and mattress mechanism is smaller, lighter and more efficient. As you can see now, it works perfectly, and I don't have to climb up on the greenhouses to help it like you have to with the government model. My fellow villagers have used it for more than a year now and they all love it.

What is your plan with the machine?

I hope every vegetable farmer in China can benefit from it and increase their income without labouring like a slave.

Take me for example; now I'm not just growing vegetables out of season, but have added quite a few exotic crops. People are no longer satisfied with the usual varieties of farmed vegetables and herbs. They want to eat varieties usually gathered in the wild and are willing to pay extra for them.

I am now one of the wealthiest farmers in the village, richer than an ordinary university graduate sitting at the county office. This is possible because I now have a tool that can free me from a labour-intensive task, giving me more time to use my brain.

I have obtained a patent for the design and I hope some factories will put it into production.

I have written to the provincial and central governments offering to donate my patent to the nation if the government can help promote the technology. It has been quite a few months but nobody seems to be interested enough to write back or give me a call. I am disappointed. On television all the leaders seem to care a lot about farmers.