Temperature Spec

The temperature system will:

  1. Measure temperature

    1. Over the range of 0-70\(^{\circ}\)

    2. With accuracy of 0.5\(^{\circ}\)

    3. 4/5 sensors throughout bath

    4. Corrosion resistant

    5. Every 5 seconds

  2. Convert signal (digital - mV (temp))

    1. With accuracy of 0.5 \(^{\circ}\)

  3. Determine signal to send to heater

    1. Using set point and PI control

    2. Comparison of last 5 readings? (average? ignore anomalies?)

    3. Every 5 seconds

  4. Signal to heater

    1. Using PWM

  5. Heat solution

    1. Using PWM

    2. Using opto-isolator and transistor

    3. Max T of heating element \(\approx\) 100\(^{\circ}\)

The microcontroller will:

  1. Take in data from ADC

  2. Compare to set point

  3. Use PI control as necessary to give out PWM signal to adjust temperature of heating element.

Power Supply Specification

The power supply must:

  1. Accept mains electricity

    1. Interface to BS1363 socket

    2. Accept  240VAC

    3. Draw less than 1A

  2. Supply power to electrodes

    1. Vary voltage in range 0-20V to  5mV

    2. Vary current in range 0-1A to  5mA

    3. Vary waveform

    4. Reverse current (see **PRC**)

  3. Measure power to electrodes

    1. Measure voltage in range 0-20V to  5mV

    2. Measure current in range 0-1A to  5mA

  4. Control power to electrodes

    1. Adjust voltage output to match voltage set point

    2. Adjust voltage output to match current set point

    3. Accept voltage/current set points

  5. Be safe to use

    1. Have no exposed mains connections

    2. Have a mains fuse for protection

    3. Have no exposed DC connections (except to electrodes)

    4. Have override power off switch

  6. Supply auxiliary power to other subsystems

    1. Power micro-controller (3.3V)

    2. Power actuators 5V/12V

Bath Specification

The system will:

  1. Contain solution without leaks

    1. Be self-contained

    2. No holes drilled through bath

    3. Prevent overflow

    4. Contain an overflow pipe above required height of solution for plating

    5. Self-contain fluid

    6. Polypropylene pipe to facilitate draining

    7. Drain fluid

    8. Contain well sealed drain hole and plug at bottom of tank

    9. Polypropylene pipe to facilitate draining

  2. Dimensions of bath

    1. Have maximum dimensions of 25/25/25cm

    2. Have minimum dimensions of 10/20/20cm

    3. Allow simple application of anode and cathode

    4. Discharge fumes to ambient

  3. Facilitate growth of a single part

  4. Interface simply with aluminium chassis

    1. Be of dimensions which are appropriate to chassis

  5. Be non-corrosive to acidic solutions

    1. Have excellent resistance to CuSO4

    2. Bath will be manufactured from polypropylene or PVC

    3. All metal parts will be 316 stainless steel

  6. Contain a plastic false bottom

    1. Contain bracket to allow easy insertion

    2. Be made of polypropylene

  7. Facilitate application of honeycomb structure

  8. Be safe

    1. Protect user from solution

    2. Withstand applied heat

    3. Be intuitive and easy to use

    4. Not leak

Chassis Specification

The chassis must:

  1. Support other subsystems

    1. Support bath

    2. Support cathode movement subsystem

    3. Support anode

    4. Support agitation mechanism

    5. Support temperature measurement devices

    6. Support temperature actuation subsystem

    7. Support pH measurement devices

    8. Support pH actuation subsystem

    9. Support specimen measurement subsystem

  2. Support system electronics

    1. Support PCBs

    2. Support PSU

  3. Be safe to use

    1. Protect user from electronics

    2. Protect user from chemicals

    3. Protect subsystems from damage