I went shopping for Robots, and there were several that caught my eye. First off, as I was looking at the robots there were two criteria that were important to me.
#1. The robot could not come pre-built. I wanted something that Martin would have to assemble himself. All of these robots fall into that category. In fact, many of them can be disassembled and rebuilt into different configurations.
#2. The robot could not be driven Primarily by remote control. I wanted a robot that was truly programmable. Many of these have remote controls, but the controls have been programmed to execute a pre-programmed set of commands.
I found FIVE robots that I felt were appropriate for him. My favorites on the list are the first and the last, the "Thames & Kosmos" and the "OSOYOO".
First is the Thames & Kosmos "Kai" Robot. I liked this one because it it the most intelligent of the robots. This one actually has an AI module in it which can learn. The downside is that it has one configuration, so once it's built, it's built.
The next two I was looking at were two of the Apitor robots, namely the Robot J and Robot X (both advanced models). The down side of these robots is that they are essentially toy Lego robots, but at the same time the fact that they're Lego means that these two could be disassembled and reassembled in multiple different configurations. Both of these robots come with fully programmable remote controls, but the controls only allow you to program the wheels, so only one part of the robot can be controlled.
The last two I liked were the MakeBlock mBot and the OSOYOO Smart IOT Robot Car. What I liked about these two is that they looked to be the most technologically advanced from the construction point of view. I other words these robots required a fairly high knowledge and understanding of electronics and circuitry. They have a few different configurations, but their "rebuildability" is limited. Still, these two bots appear to be fairly intelligent.