# Starling MAX

Source: https://forum.modalai.com/topic/3837/starling-max
Category: Development Drones (https://forum.modalai.com/category/44/development-drones)
Posted: 2024-09-27 19:08:44 UTC by Thomas Eiszler
Replies: 5 · Views: 4003

## Thomas Eiszler · 2024-09-27 19:08:44 UTC

Hello,

We had to replace the power/ESC module on our Starling MAX and now we cannot arm the drone. voxl-esc scan seems to detect the ESC, but perhaps we are missing some configuration. There are a number of setup_ commands for voxl-esc, but it is not clear which applies to the Starling Max. How can we set up the new ESC?

Thanks,
Tom

## Reply by tom (ModalAI staff) · 2024-09-27 19:30:54 UTC

@Thomas-Eiszler I would recommend just running `voxl-configure-mpa` which will ensure you have the correct services configured and running as well as check the ESCs firmware and params and will update them if necessary

## Reply by Thomas Eiszler · 2024-09-30 12:57:58 UTC (in reply to tom)

Thanks @tom! That seems to have worked. After configuration, I ran voxl-esc spin and all 4 rotors spun up in turn. Just another quick question about the output. 

```
Finished!
[4.992197] TX=504, RX=1000 packets, RX CRC ERRORS=0
Average RPMs: 0.00 0.00 0.00 1998.98
Average RPM deviation between ESCs : 1998.98
disabling bridge
```

Is this just a quirk in the way the average RPMs are reported or should I be concerned that 3 of the 4 have a 0 average? They definitely all spun up, and seemed to reach the same speed.

## Reply by Thomas Eiszler · 2024-10-01 13:04:21 UTC (in reply to Thomas Eiszler)

@tom  There is also another anomaly: voxl-inspect-battery shows voltage and current, but charge is listed as 0%. Is there some service that needs to be restarted/configured, like voxl-px4, in order to get a reading of the battery charge?

I also ran px4-listener battery_status which also doesn't seem right. The cells that came with the Starling MAX I believe are 7.2V (two 2s in series, so 4 cells total). 

```
voxl2:/$ px4-listener battery_status

TOPIC: battery_status
 battery_status
    timestamp: 1051478873 (0.067609 seconds ago)
    voltage_v: 5.76600
    voltage_filtered_v: 5.76056
    current_a: 1.00800
    current_filtered_a: 0.96054
    current_average_a: 3.40000
    discharged_mah: 299.21326
    remaining: 0.00000
    scale: 1.30000
    time_remaining_s: 0.00000
    temperature: nan
    voltage_cell_v: [0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000, 0.00000]
    max_cell_voltage_delta: 0.00000
    custom_faults: 0
    average_power: 0.00000
    available_energy: 0.00000
    full_charge_capacity_wh: 0.00000
    remaining_capacity_wh: 0.00000
    design_capacity: 0.00000
    nominal_voltage: 0.00000
    capacity: 3950
    cycle_count: 0
    average_time_to_empty: 0
    serial_number: 0
    manufacture_date: 0
    state_of_health: 0
    max_error: 0
    interface_error: 0
    faults: 0
    average_time_to_full: 0
    over_discharge_count: 0
    connected: True
    cell_count: 4
    source: 0
    priority: 0
    id: 1
    is_powering_off: False
    is_required: False
    warning: 3
    mode: 0
```

Do I need to change the POWER_MANAGER in /etc/modalai/voxl-px4.conf from VOXLPM to NONE and restar the voxl-px4 service? The comments seem to indicate that we should be using NONE with the Mini-ESC 4 in1:

```
# POWER_MANAGER:
#     Tell PX4 which power manager to use.
#     Use NONE for ModalAI Mini-ESC since the ESC driver handles PM.
#     Use EXTERNAL when not using the ModalAI APM power manager to power the board
#       This also just disables the voxlpm driver, same as the NONE option
#     Options include: [VOXLPM, EXTERNAL, NONE]
```

## Reply by Alex Kushleyev (ModalAI staff) · 2024-10-05 04:23:11 UTC (in reply to Thomas Eiszler)

@Thomas-Eiszler , what test command did you use for the case where 4 motors spun up but the only ID3 reported feedback?

```
Finished!
[4.992197] TX=504, RX=1000 packets, RX CRC ERRORS=0
Average RPMs: 0.00 0.00 0.00 1998.98
Average RPM deviation between ESCs : 1998.98
disabling bridge
```

The number of TX and RX packets indicate to me that you most likely only spun ID3 of ESC in this test because you have double RX packets than TX (ID3 seconds out normal feedback packet and another one with current measurment for the whole board).

voxl-esc spin probably only spun one motor at a time, in which case this is the expected behavior, and we should probably update the script to not report the deviation if only one motor was actually spinning in the particular test.

Alex

## Reply by Alex Kushleyev (ModalAI staff) · 2024-10-05 04:28:04 UTC (in reply to Thomas Eiszler)

@Thomas-Eiszler , As long as you dont actually have the APM connected, having the power manager driver enabled in PX4 will not conflict with the mini ESC also reporting battery_status. This is because even though the APM driver in PX4 will attempt to start, it will fail to find the actual hardware device (via i2c probe) and will exit the driver. However, it is best to disable the power manager (APM) driver.

Starling 2 MAX uses two 2-cell packs in series, so it is a 4-cell pack.

when you run `voxl-esc spin` test, it should report voltage reported by each ESC. Does that match the actual battery voltage or is it also wrong (as is reported in your `battery_status` ?

Alex