I am looking to buy a range finder module for an obstacle avoidance robot. Currently, two good options based on available libraries and compatibility with Arduino and rPI are HC-SR04 and parallax ping.
In terms of form factor these seem the same. The only difference I can tell is 4 pins vs 3 pins. Also the price, with parallax being more than x4 the price. As I would rather not buy something cheaper which will need replacing, is anyone aware of further differences, that will make the parallax a better option?
both need 5V both have max range of 3-4m Sensor angle HC- 15 degrees, parallax cant find..