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Week four (20/02/24) Final circuit diagram A new LCD display was found, and this was used instead and worked fine, however, this LCD required different circuitry to connect it, so this was done. The algorithm for calibrating the machine was changed, we hit each LED 20 times and measured the average ratios of sensor 2 and sensor 3 compared to sensor 1. These ratios could then be used to estimate the location where the hammer hit the acrylic sheet in future hits.
Week three (13/02/24) Initial circuit diagram Breakout board for the LCD display arrived (this was required because the pins on the LED display were closer together than the tracks on Veroboard). Completed transferring the circuit to Veroboard, most of the circuit was housed inside a small box. We made a hole in the back of this box for all the wires to go through. LCD display did not work, the cause of this is unknown.
Week two (06/02/24) Tried using filters to remove noise and found that they were unnecessary. Tried peak voltage circuit and found that this was unnecessary since the Pico has high enough sampling rate. Built and connected a voltage divider for each of the piezos so that the input to the Pico would always be less than the maximum of the ADC. Basic calibration programmed in Arduino to compensate for some sensors being more responsive than others. Extensive testing to ensure that the wac a mole was working ok. Began transferring the circuit to Veroboard.
Week one (31/01/24) Assembled the wac a mole board and the rig to test it. Extended component legs of LEDs and Piezoelectric sensors by soldering wires onto them. Mounted LEDs and piezos, using hot glue for LEDs and tape to attach the sensors. Tested LEDs to ensure that they worked correctly. Tested piezoelectric sensors using a 4-channel oscilloscope and found that they would be useable for detecting the approximate position of where the hammer hits the wac a mole using the maximum amplitude of the waveform with readings occasionally of over 5V from the sensors, though typically the peak voltage measurements were around 1 Volt. These results confirmed that amplifiers would not be required for the circuit, instead voltage divider circuits would be needed since the ADCs in the Pico have a maximum voltage of 3.3 Volts. ...