My son is mad on the robot from Short Circuit (Johnny 5) and I want to build robots with him. We have a copy of Daniele Benedettelli's "Creating Cool Mindstorms NXT Robots" and I was planning to start with the simpler Johnny 5 build (miniJohnNXT) which is on the author's website. We only own simple Lego at the moment so I need to invest in a kit which has bricks, sensors etc. So I have a few questions. I've looked around the web but most questions focus on NXT/EV3 compatibility of hardware, not software.
Which kit should I buy given that we want to build the miniJohnNXT (but will obviously also do other builds)? The NXT kit (8527, currently about £170), the EV3 retail kit (31313, currently £218) or the EV3 education kit (45544, currently £371)? I realise I'll have to get extra parts whichever kit I get, but the brick seems the main cost.
Will the code written for the NXT brick to control Johnny5 work on the EV3 brick? (I assume so, but need to check)
Given that the "eyes" part of the robot is an ultrasonic sensor (53792) in the NXT kit, and in the EV3 retail kit is an IR sensor (95654), will this cause big problems with the coding, or can I just modify it relatively easily (or put and ultrasonic sensor elsewhere on the robot?).
My gut feeling is to get the EV3 retail kit as the EV3 brick is newer technology than NXT, so likely to be more forwardly compatible (I think we have years of Lego ahead of us) and the EV3 education kit seems really overpriced, but if the coding won't work except with NXT then I'll get an NXT kit instead.