After we received the motor on the screw rod this week, we connected it to the motor driver and managed to use codes on RPi to control its speed and direction. However, one significant risk that could jeopardize the success of the project is that with the screw rod and the NEMA 17 motor we chose, the maximum speed of the motor moving is still too slow for board erasing. After researching the alternative screws online, we have found a screw rod with 4 times wider thresh and a NEMA 23 motor that could fit in the screw rod, which is supposed to move 4 times faster than the solution we currently have. Therefore, we placed an order for the new screw and motor to address this risk. We have also come up with a backup plan that uses motor-controlled strings connected to the two sides of the linear slide to move the linear slide in case the speed of NEMA 23 is still too slow.
Besides that, there is no other major change to our system. One minor change is to add several lumber blocks at the back of the board to support the board as well as the linear slide at the top of the board. This change is necessary to address the safety concern we have discussed during the ethics assignment. Therefore, we have placed orders for that lumber together with other wood sheets and will spend next Friday together to laser cut the wood plates and assemble the attachment.