This controller is an upgrade of 02_Radio_PID_Controller and retains most of the design features of the previous controller with the following modifications:
- 5V power regulation is improved
- LED connections and resistors are integrated
- Some bottom routing is redesigned for easier soldering.
This clamp controller can achieve the following goal (with proper firmware):
- Control and communicate through CC1101 radio module. (SPI)
- Control 1 or 2 motors for the clamp's main linear movement
- PWM / Bidirectional output via XY160D driver to two DC motors
- Close loop feedback from two-phase hall effect shaft encoder from 2 motors
- Operate on 3 or 4-cell Li-Po Battery power
- Monitor homing switch / pneumatic autoswitch
- Monitor battery voltage
- Output for 1 or 2 LED status light
Battery Choice: Up to user (typical: 4-cell Li-Po 1000mAh 4S 75C)
Radio Choice: CC1101 Module
Motor Driver Choice: Motor Driver XY160D
MCU Choice: Arduino Nano (ATMEGA328 with new bootloader)
Voltage Regulation: Single stage LM7805 solution (see schematic)
Addressing / Settings DIP Switch: 4 position DIP switch with resistor ladder
End Switch Choice: Normal close (NC) switch
This board is built on protoboard, the following board shows mostly the hard wiring underneath the protoboard. There are jumpers that routes from top side not drawn here.
The Controller in enclosed case with plugged in battery. The disconnected cables goes to DC motor with encoder.
Arduino Nano and radio module (Blue PCB with antenna) on protoboard. The Motor driver (red PCB) can be seen below the protoboard.
| 1 motor operation | 2 motor operation | |
|---|---|---|
| Homing Switch | 1 switch (A1) | 2 switches (A1, A2) |
| Gripper Autoswitch | 1 input (A2) | not available |
| Motor Encoder 1 | interrupt (D2) | interrupt (D2, D3) |
| Motor Encoder 2 | interrupt (D3) | gpio (A4, A5) |
| Motor Status LED (orange/red) | D6 | not available |
During the third phase of the project the power regulation is modified. The LM7805 is removed and a LM2596 DC-DC converter module is placed in the same role. This improved the regulation efficiency during standby mode and particularly important with the addition of the ESP32 CAM module. The ESP32 CAM draws substantial current and (confirmed by test) cannot be supported by the 7805, causing it to run into thermal protection.
| Device | Current Draw @14.8V (LM7805) | Current Draw @14.8V (LM2596) |
|---|---|---|
| Controller with No Radio | 0.055 | 0.1 |
| Controller with Radio | 0.056 | 0.116 |
| + ESP32 CAM | 0.1 | 0.23 |
| + ESP32 CAM LED On | 0.15 | 0.358 |
The new LM2596 module is not integrated to the same PCB but is wired off-board and is fixed with foam tape to the side of the worm gearbox.