Anti-submarining ramps don't have anything to do with submarines, I'm afraid.
During a car crash, when a person slides underneath the seatbelt, that is called submarining. The seatbelt slides up onto the stomach, and can cause injury.
An anti-submarining ramp is a ramp built into the seat cushion, underneath the foam padding, that helps to prevent the person from sliding forward on the seat underneath the seatbelt. This keeps the seatbelt in the proper position on the person's pelvis, and helps to prevent injuries to the stomach.
Swimming Boating Submarining Snorkeling
"Portable ramps are most beneficial to people in a wheelchair, because a lot of places do not have wheelchair ramps installed." People in wheelchairs will take portable ramps with them to be able to enter older buildings that are without wheelchair ramps.
Wheelchair ramps, ramps up parking garages
in ramps and driveways.
Skiing ,snowboarding, skateboarding, etc are the examples of ramps.
You can get blackriver ramps in the US online on flatfacefingerboards.com
screw,ax slide are ramps - Eljana
Discountramps.com is a website where you can purchase truck loading ramps online. They offer a wide variety of ramps to choose from.
Yes, transportable wheelchair ramps are actually fairly common. Two large companies that manufacture such ramps are handiramp and literamp.
Ramps for motorcycles can be bought from a number of retailers. For example, they can be ordered from Amazon, or they can be purchased from a website dedicated to ramps called Discount Ramps.
Ramps are considered to be a simple machine. It uses an inclined plane to quickly move items. Wheelchair ramps represent a traditional example of this slope.
No insurance that I've ever had required ramps.