If you have a motorhome you will know how easily they can get stuck on wet grass. A couple of years ago in France we saw a van up to the mudguards digging in on every turn of the wheel. People tried to help using all the flimsy plastic tread mats which just disappeared into the mud. Then someone came up with these traction ramps. They are designed for off road 4x4 and can take the weight of a Land rover across mud holes.
I bought two from ebay for £40 and we have used them every time we pitch up on grass. They work great to prevent the van sinking into the grass if you are staying for a few days. They have also got us out of trouble on a number of occasions when the weather has turned bad and we need to get of the grass.
As you can see in the photo I have fevered my ramps off each end. This is to prevent them ticking up when driving on and off them. I did this using a small angle grinder. Remember this is fiberglass and so you will need to wear all the protective equipment when grinding them down.
To store them I have made a small box as shown in the picture. This is made from 6mm ply making it very light and I have given it a coat of epoxy to water proof it then gloss white to make it the same colour as the van. This is bolted with U bolts to the bike rack so it is out of the way and the bike rack can still be used. This makes for easy access when needed and they can go back in dirty.
They are very strong and well worth the cost. Getting stuck in the mud can be a big problem especially if you are wild camping and have no one around to help you out of the mud. However I don't think it will be any help to the guy in the picture below.