Today, if you go looking for a robot to use in your house you really only have a few options to choose from. The first type of product is a single task system like a vacuum that is really more of an appliance. Another option is to get something that is basically a smartphone on a stand. It can move and interface with smart appliances in your house but really can't do anything your phone can't. The last choice is a robot for the sole purpose of entertainment. These machines are meant to be friendly and interactive thus replacing a dog (or friends). The Jetsons-style home robots that cooks dinner, does the wash, and has an attitude does not exist at a commercial level.
So why isn't Rosie in our kitchen yet? Well a big part of it is cost. The robot that is closest to what we imagine as a home robot is the PR2 (personal robot) developed by Willow Garage. The PR2 has two arms, each with a human-like 7 degrees of freedom and can roll around. It is outfitted with dozens of sensors and has the capability to do just about anything. But the PR2 costs 400,000 dollars.
The cost of the PR2 is due to a couple of reasons. The first is that there is no economy of scale. Since its introduction in 2007 there have only been a few dozen or perhaps a couple of hundred made (no actual numbers have been released). With such a low volume, but still needing to pay salaries the margins on robots like the PR2 are necessarily huge. But note that the markup is not so great that the robot would be affordable if it were sold at cost. PR2s for education have been released at as low as $150,000 which is very likely near the cost of the robots. So it is reasonable to assume that on the low side the PR2 costs around 100,000 dollars, in parts, to make. And since there is still the time and effort of assembly, that number is likely higher. Now why is that price so high? The answer is robots are machines not computers.
Robots are composed of motors, and gears, and magnets, oh my! Physical materials such as these have a floor price that they may achieve based on limited supply. Unlike chips, magnets do not get exponentially cheaper, because we can only extract and process so much neodymium. So even with an economy of scale, robots will be expensive due to the cost of raw materials. Looking at the PR2. It has two arms, each with seven motors and the grippers. Then there are the four drive wheels and their articulation. As well as any other actuation for sensors. Those components, which are high performance, along with the gearboxes and other custom mechanics could easily run up to around 50,000 dollars. And that is before the sensing and computing are installed, which, though getting cheaper, are still expensive.
Essentially, robots are expensive because they are currently custom, high performance machines. Slant built Jerry to be practically the opposite of that. Jerry is designed to be manufactured affordably by a guy in a garage.
The first step we took in this direction was to make Jerry out of wood. Wood was an ideal material because, not only it is beautiful and affordable, it is a simple material to train people to work with, so skilled labor can be used affordably until a factory can be made.
Jerry addresses the primary issue of motors by reducing them. He uses a basic differential drive system that allows for effective locomotion with only two motors. The arm actually only has two degrees of freedom and a gripper. But the design is efficient enough to give Jerry a work space, from the ground to his gripper, 38 inches high. The arm is able to move up and down as well as forward and backward. Any side-to-side motion can be performed by his drive wheels. This system is a bit more complex than a 7 DOF arm as far as software is concerned, but it was simpler mechanically. and since mechanics are what causes the cost to the customer that is what we focused on.
Additionally, Jerry is minimalist on sensors. He relies almost entirely on his vision system to perceive himself and the world. This was chosen because vision has the capability to provide all the information that could be needed about the world as long as a computer is powerful enough to glean that information, which they are.
Jerry has been designed to be affordable through reducing expensive mechanics and replacing it with cheap computing. All this has resulted in a robot that is capable of any number of tasks and will cost around $2500. So now you have an option of buying a robotic swiffer for around $400 or getting a true home robot that can grab a swiffer, walk the dog, monitor the house, and any number of other things for $2500.