A man in Vietnam has built his own remote-controlled trolly to take vegetables into alleys and neighbourhoods that have been locked down because of Covid-19 outbreaks. The remote control car was built by Mr Nguyen Vinh Duy for the purpose of delivering food to isolation areas. The vehicle can be controlled a maximum distance of 500 metres (1640 feet) from the controller, with a load of 200kg (441 lbs), and can operate continuously for four hours. The maximum speed is 20kmph (12.4 mph) and it cost about 80 million VND (around 3,500 US dollars) to make. Interviewed, he said: "Although I have worn a mask, it is not necessarily safe, so I created this car to ensure a distance of over 20 meters, to ensure safety during the delivery of goods to the isolation areas. It took me 17 days. The car includes the main engine, deceleration system, differential lock, magnetic brake system so that the car can brake itself. It has four wheels and four shock absorbers to be able to run on many terrains. It is also capable of self-disinfection after finishing the task." "The most difficult part in the manufacturing process is calculating the gear ratio and the chassis system, it must be correct so the operation is durable and smooth. The electronic circuit system must ensure safety and stability during use. Materials include commercially available irons, electronic boards you have to program, print and assemble yourself. The cars after me will make the load bigger and the speed faster because it's still not faster than by hand, but a little slower is better than a lifetime."