Summary 20/09/2010. INTRODUCTION pressing need for LAND benefits in investing in agriculture

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1 Toward LOCOSTRA Results from a comparative test on blast resistant wheels Emanuela Elisa Cepolina PMARlab, DIMEC, University of Genova, Italy Snail Aid Technology for Development 6 September 2010, 3rd Mine Action Technology Workshop, Geneva, Switzerland INTRODUCTION pressing need for LAND benefits in investing in agriculture Summary LOCOSTRA Project aim Tractor Innovative components Time and budget WHEELS TEST wheels test organization test results CONCLUSIONS 1

2 2010 major facts about land wide spread crisis: energy and food increase in farmland grabbing phenomenon (northern countries or companies getting southern land) both for biofuel and food production The Global Land Rush: Can it yield sustainable and equitable benefits? Draft version criticizes land grabbing for not meshing with proper development strategies and leading to conflict major facts about land vulnerability of poor countries on weather and economic shocks (no resilience) linked to investments in agriculture From 1980 development aid by 250% agriculture aid by half investments in agricultural science and technology are key to improve resilience 2

3 2010 major facts about land moral imperative to release mine affected land quickly food security, energy source if agri-tech are used win-win solution resilience, long term development if countries are efficient users of their land, they are less likely to be grabbed Co-funded by: Partners: Italian Ministry of Economic Development and Italian Institute for Foreign Trade University of Genova, Italy Norwegian People s Aid Jordan 3

4 Aim: LOCOSTRA project Low Cost Tractors for Humanitarian Demining Develop a tractor-based machine for ground processing in technical survey process of land release, cheap, < small robust using local facilities and material modular: innovative parts could be used in similar applications, different machines The machine can be used in agricultural practices when not employed for demining, centres to service the machine can be used to develop new agricultural technologies to improve resilience Design: LOCOSTRA project 4 WHEEL - MINI TRACTOR slightly modified with: essential REMOTE control light armouring new BLAST resistant wheels all made with COTS components TEST in the field and dissemination of results to mine action community 4

5 4 wheels mini tractor: LOCOSTRA project Engine: 79hp, diesel Weight: 1850 kg 4WD Reversible Brakes: 4 disc brakes Steering: hydraulic, double Hitch system: 3 point, lift capacity: 1800kg LOCOSTRA project COTS components: Tractor Agricultural implements: vegetation cutters, ground processing tools Innovative components: External remote control: control distance:100m dual: not interfering with on board control essential: forward/backward motion speed central and frontal steering 3 point linkage system differential gear blockage p.t.o brakes and emergency stop simple HMI Armouring (only for AP mines, 200g of TNT): deflection plates of 3mm thick mild steel kevlar/aramid coverings for hydraulic hoses kevlar/aramid curtain 2 electro-hydraulic valves 6 hydraulic valves 1 relay 1 switch 5

6 Time and Budget LOCOSTRA project Time: 18 months Budget: co-funded for Activity Month n Nov09 Dec09 Jan10 Febr10 mar-10 apr-10 May10 June10 July10 Aug10 Sept10 Oct10 Nov10 Dec10 Jan11 Febr11 Mar11 Apr WP1: Remote control and armouring design manufacturing test and evaluation re-design re-manufacturing and test WP2: Blast resistant wheels (supervision AVS) design avs avs avs ed ed ed manufacturing ed ed test and evaluation re-design avs ed DC DC re-manufacturing and test WP3: Prototype test and evaluation analysis of mobility, tractive performance and maximum drawbar pull tractor shipping to Jordan test and evaluation (live area in Jordan) re-design in field trial WP4: Administration and Dissemination of results organizational, administrative and financial coordination administrative project managenet operating instructions and SOPs writing and publishing money spent until now: ,85 almost 50% Blast resistant wheels general requirements: withstand 200g of TNT and resist at least 5 explosions before replacement keep the tractor safe by reducing to harmless level the shock wave transmitted to the hub low cost easily to be repaired locally good traction light 6

7 Wheels 4 different designs made with the very important help of Andy Vian Smith and Ed Pennington Ridge Wheels 1. vented steel wheel All Steel diam: 900mm, m: 85kg, steel thickness: 4mm 2 and 3 with inflatable wheel inside 2. small - Florida diam: 900mm, m: 86kg, steel thickness: 4mm inflatable diam: 500mm 3. big - EPR diam: 890mm, m: 161kg, steel thickness: 10mm inflatable diam: 750mm 4. with solid rubber wheel inside - Genoa diam: 865mm, m: 118kg, steel thickness: 4mm solid rubber diam: 595mm 7

8 Test aim Compare the 4 wheel designs to assess which wheel performs better at resisting physical damages reducing significantly the energy associated with the blast wave transferred to the tractor Sensors to measure energy reduction, on ballistic pendulum: encoder rotational displacement of pendulum arm accelerometer on wheel axis Test data location: gravel quarry Valcena near to Parma, Italy date: 28 th May and 4 th June 2010 Test team: Istituto Ricerche Esplosivistiche, I.R.E. Agenzia Industrie e Difesa Pierre Trattori University of Genova AVS Mine Action Consultants Elegant Design and Solutions Testing rig still in quarry for next tests 8

9 Testing rig sensors: encoder, accelerometer, pressure transducers, high speed camera, 3 traditional cameras charges: 120g of Goma2 Eco, 120g of TNT (powder), 240g of TNT (powder) soil: thermalite block - tests consistency explosions sequence: Evaluating results Mechanical integrity, assessing loss of any part splitting of material between welds cracking of welds permanent deformation of steel parts permanent deformation of rubber parts Energy transferred (potential) max. rotational displacement angle of pendulum arm Acceleration RMS value total and on x,y plane + z axis 9

10 Evaluating results Mechanical integrity tractor, bearing ½ h drive after the explosions!!! when dismantled, little damage to axis bearing NOT affecting bearing life Mechanical integrity - wheels defomration value plastic deformation All steel Florida 2bar Genoa Genoa on tractor 1 2 All wheels have scored YES in their ability to turn 120g of Goma2Eco 120g of TNT 240g of TNT EPR 1,7bar EPR on tractor Series1 Series2 Series3 3 wheel 4 due to ovalization Evaluating results 120g of Goma 2 Eco 120g of TNT 240g of TNT 10

11 Evaluating results Energy transferred encoder angle (Ep=m*g*h) energy (potential) transferred 3,00 2,50 encoder angle 2,00 1,50 1,00 0,50 Series1 120g of Goma2Eco Series2 120g of Series3 TNT 240g of TNT 0,00 All steel Florida 2bar Genoa EPR 1,7bar w heel angle measured Evaluating results Acceleration Root Mean Square (RMS) average value of acceleration over time RMS acceleration 600,00 500,00 a [m/s^2] 400,00 300,00 200,00 100,00 120g Series1 of Goma2Eco Series2 120g of TNT Series3 240g of TNT 0,00 All steel Florida 2bar Genoa Genoa on tractor EPR 1,7bar EPR on tractor wheel Very different behaviour of large inflatable wheel when mounted on the tractor Solid rubber wheel performs better against higher quantities of explosive 11

12 Evaluating results Acceleration Root Mean Square (RMS) x,y plane and z axis z component of acceleration is often higher than x and y combined Results of general interest 1. Inflatable wheels work worse when mounted on the tractor 2. Solid rubber wheels perform better against higher quantities of explosive 3. Acceleration on the wheel axis is often higher than on the wheel plane 12

13 20/09/2010 Results of general interest 1. Inflatable wheels work worse when mounted on the tractor inflatable tire inside wheel works as a set of radial springs: when the wheel is free to jump up and down (pendulum) internal movement help dissipating energy Results of general interest when mounted on the pendulum, against 120g of TNT, Florida wheel has an inner jump of 73mm in 1/50s, while the axis doesn t move 13

14 Results of general interest 1. Inflatable wheels work worse when mounted on the tractor inflatable tire inside wheel works as a set of radial springs: when the wheel is on the tractor, it jumps much less Results of general interest 2. Solid rubber wheels perform better against higher quantities of explosive rubber dissipates energy by hysteresis cycles higher quantity of explosive actuates more rubber the more soft rubber the better 14

15 Results of general interest 3. Acceleration on the wheel axis is often higher than on the wheel plane acceleration on z axis is often higher than on x, y axes a = F/m = p*a/m a proportional A Results of general interest BEST wheel out of the 4 tested has solid rubber wheel (forklift truck) outer steel 4mm thick BEST wheel in general has solid SOFT rubber wheel as large as possible outer steel rigid structure presenting the maximum number of holes for venting 15

16 Acknowledgments Donors: Italian Ministry for Economic Development Italian Institute for Foreign Trade All LOCOSTRA partners and to Technical Department of Italian Ministry of Defence Conclusions If we use agricultural machines for land release, achieve a double goal great impact on mine action and development blast resistant wheels can easily be made by integrating rubber wheels within a steel outer RMS acceleration structure 600,00 500,00 a [m/s^2] 400,00 300,00 200,00 Series1 Series2 Series3 100,00 0,00 All steel Florida Genoa Genoa on EPR 1,7bar 2bar tractor wheel more detailed report on next issue of JMA EPR on tractor 16

17 Evaluating results Acceleration Power Spectrum Density (PSD) power of signal per frequency (integrated over the frequency domain: 0-700Hz) PSDxyz acc , ,00 PSDxyz [(m/s^2)^2] 50000, , , , ,00 Series1 Series2 Series3 0,00 All steel Florida 2bar Genoa Genoa on tractor EPR 1,7bar EPR on tractor wheel 17

18 A negative vision population growth -> need of quick release of land more landmines mine affected land not released new war A positive vision R&D centres for agricultural technologies smallholder farmers owner of their land reduce vulnerability release land improve food production, self-sufficiency 18

19 120g of Goma2 Eco 120g of TNT 240g of TNT 19